| 1. |
- Andersson, Annica, et al.
(författare)
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Relationship of grain fructan content to degree of polymerisation in different barleys
- 2014
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Ingår i: Food and Nutrition Sciences. - : Scientific Research Publishing, Inc.. - 2157-944X .- 2157-9458. ; 5, s. 581-589
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Tidskriftsartikel (refereegranskat)abstract
- Fructans are important in the survival of plants and also valuable for humans as potentially health promoting food ingredients. In this study fructan content and composition were determined in grains of 20 barley breeding lines and cultivars with a wide variation in chemical composition, morphology and country of origin, grown at one site in Chile. There was significant genotypic variation in grain fructan content ranging from 0.9% to 4.2% of grain dry weight. Fructan degree of polymerisation (DP) was analysed using high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD). Changes in the distribution of different chain lengths and the pattern of structures of fructan were detected with increasing amount of fructan in the different barleys. A positive correlation was found between fructan content and the relative amount of long chain fructan (DP > 9) (r = 0.54, p = 0.021). Our results provide a basis for selecting promising barley lines and cultivars for further research on fructan in barley breeding with the aim to produce healthy food products.
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| 2. |
- Aslan, Selcuk, et al.
(författare)
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Increased production of wax esters in transgenic tobacco plants by expression of a fatty acid reductase:wax synthase gene fusion
- 2015
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Ingår i: Transgenic Research. - : Springer Science and Business Media LLC. - 0962-8819 .- 1573-9368. ; 24, s. 945-953
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Tidskriftsartikel (refereegranskat)abstract
- Wax esters are hydrophobic lipids consisting of a fatty acid moiety linked to a fatty alcohol with an ester bond. Plant-derived wax esters are today of particular concern for their potential as cost-effective and sustainable sources of lubricants. However, this aspect is hampered by the fact that the level of wax esters in plants generally is too low to allow commercial exploitation. To investigate whether wax ester biosynthesis can be increased in plants using transgenic approaches, we have here exploited a fusion between two bacterial genes together encoding a single wax ester-forming enzyme, and targeted the resulting protein to chloroplasts in stably transformed tobacco (Nicotiana benthamiana) plants. Compared to wild-type controls, transgenic plants showed both in leaves and stems a significant increase in the total level of wax esters, being eight-fold at the whole plant level. The profiles of fatty acid methyl ester and fatty alcohol in wax esters were related, and C16 and C18 molecules constituted predominant forms. Strong transformants displayed certain developmental aberrations, such as stunted growth and chlorotic leaves and stems. These negative effects were associated with an accumulation of fatty alcohols, suggesting that an adequate balance between formation and esterification of fatty alcohols is crucial for a high wax ester production. The results show that wax ester engineering in transgenic plants is feasible, and suggest that higher yields may become achieved in the near future.
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| 3. |
- Aslan, Selcuk, et al.
(författare)
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Transient silencing of the KASII genes is feasible in Nicotiana benthamiana for metabolic engineering of wax ester composition
- 2015
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 5
-
Tidskriftsartikel (refereegranskat)abstract
- The beta-ketoacyl-ACP synthase II (KASII) is an enzyme in fatty acid biosynthesis, catalyzing the elongation of 16:0-acyl carrier protein (ACP) to 18:0-ACP in plastids. Mutations in KASII genes in higher plants can lead to lethality, which makes it difficult to utilize the gene for lipid metabolic engineering. We demonstrated previously that transient expression of plastid-directed fatty acyl reductases and wax ester synthases could result in different compositions of wax esters. We hypothesized that changing the ratio between C16 (palmitoyl-compounds) and C18 (stearoyl-compounds) in the plastidic acyl-ACP pool by inhibition of KASII expression would change the yield and composition of wax esters via substrate preference of the introduced enzymes. Here, we report that transient inhibition of KASII expression by three different RNAi constructs in leaves of N. benthamiana results in almost complete inhibition of KASII expression. The transient RNAi approach led to a shift of carbon flux from a pool of C18 fatty acids to C16, which significantly increased wax ester production in AtFAR6-containing combinations. The results demonstrate that transient inhibition of KASII in vegetative tissues of higher plants enables metabolic studies towards industrial production of lipids such as wax esters with specific quality and composition.
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| 4. |
- Aslan, Selcuk, et al.
(författare)
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Wax esters of different compositions produced via engineering of leaf chloroplast metabolism in Nicotiana benthamiana
- 2014
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Ingår i: Metabolic Engineering. - : Elsevier BV. - 1096-7176 .- 1096-7184. ; 25, s. 103-112
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Tidskriftsartikel (refereegranskat)abstract
- In a future bin based economy, renewable sources for lipid compounds at attractive cost are needed for applications where today petrochemical derivatives are dominating. Wax esters and fatty alcohols provide diverse industrial uses, such as in lubricant and surfactant production. In this study, chloroplast metabolism was engineered to divert intermediates from de nova fatty acid biosynthesis to wax ester synthesis. To accomplish this, chloroplast targeted fatty acyl recluctases (EAR) and wax ester synthases (WS) were transiently expressed in Nic"onana benthamiuna loaves. Wax esters of different qualities and quantities were produced providing insights to the properties and interaction of the individual enzymes used. In particular, a phytyl ester synthase was found to be a premium candidate for medium chain wax ester synthesis. Catalytic activities of FAR and WS were also expressed as a fusion protein and determined functionally equivalent to the expression of individual enzymes for wax ester synthesis in chloroplasts. (C) 2014 The Authors. Published by Elsevier Inc. On behalf of International Metabolic Engineering Society.
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| 5. |
- Baguma, Yona, et al.
(författare)
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Expression patterns of the gene encoding starch branching enzyme II in the storage roots of cassava (Manihot esculenta Crantz)
- 2003
-
Ingår i: Plant Science. - 0168-9452 .- 1873-2259. ; 164:5, s. 833-839
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Tidskriftsartikel (refereegranskat)abstract
- Spatial and temporal expression patterns of the sbeII and sbeI genes, encoding starch branching enzyme II and I, respectively, in cassava (Manihot esculenta Crantz) were studied at different phenological stages of the crop. A partial cDNA for sbeII in cassava was cloned and used along with a cDNA-specific fragment of sbeI. As the cassava plant aged, the transcriptional activity of the sbeII and sbeI genes in the underground storage roots increased, whereas the activity in other organs remained the same or declined. At 180 days after planting (d.a.p.), levels of sbeII and sbeI transcripts in storage roots were very low, whereas at 360 d.a.p., the levels had increased dramatically. The 360 d.a.p. old storage roots also accumulated gbssII and gbssI transcripts, as well as a longer gbssI transcript, gbssI′. The difference between the gbssI and gbssI′ transcripts was shown to be due to differential splicing, whereby the gbssI′ transcript retained the first three introns. Unexpectedly, expression of sbeII and sbeI in the 360 d.a.p. storage roots exhibited fluctuations during the 24 h cycle, both under the normal light/dark regime and under continuous light or continuous dark conditions.
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| 6. |
- Bannak Gedara, Shishanthi Jayarathna, et al.
(författare)
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High fructan barley lines produced by selective breeding may alter beta-glucan and amylopectin molecular structure
- 2023
-
Ingår i: Carbohydrate Polymers. - 0144-8617. ; 316
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Tidskriftsartikel (refereegranskat)abstract
- Six cross-bred barley lines developed by a breeding strategy with the target to enhance the fructan synthesis activity and reduce the fructan hydrolysis activity were analyzed together with their parental lines, and a reference line (Gustav) to determine whether the breeding strategy also affected the content and molecular structure of amylopectin and beta-glucan. The highest fructan and beta-glucan content achieved in the novel barley lines was 8.6 % and 12 %, respectively (12.3-fold and 3.2-fold higher than in Gustav). The lines with low fructan synthesis activity had higher starch content, smaller building blocks in amylopectin, and smaller structural units of beta-glucans than the lines with high-fructan synthesis activity. Correlation analysis confirmed that low starch content was associated with high amylose, fructan, and beta-glucan content, and larger building blocks in amylopectin.
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| 7. |
- Fei, Mingliang, et al.
(författare)
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Achieving of high-diet-fiber barley via managing fructan hydrolysis
- 2022
-
Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- High fructan content in the grain of cereals is an important trait in agriculture such as environmental resilience and dietary fiber food production. To understand the mechanism in determining final grain fructan content and achieve high fructan cereal, a cross breeding strategy based on fructan synthesis and hydrolysis activities was set up and have achieved barley lines with 11.8% storage fructan in the harvested grain. Our study discovered that high activity of fructan hydrolysis at later grain developmental stage leads to the low fructan content in mature seeds, simultaneously increasing fructan synthesis at early stage and decreasing fructan hydrolysis at later stage through crossing breeding is an efficient way to elevate grain diet-fiber content. A good correlation between fructan and beta glucans was also discovered with obvious interest. Field trials showed that the achieved high fructan barley produced over seven folds higher fructan content than control barley and pull carbon-flux to fructan through decreasing fructan hydrolysis without disruption starch synthesis will probably not bring yield deficiency.
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| 8. |
- Fei, Mingliang, et al.
(författare)
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Adaptation of Rice to the Nordic Climate Yields Potential for Rice Cultivation at Most Northerly Site and the Organic Production of Low-Arsenic and High-Protein Rice
- 2020
-
Ingår i: Frontiers in Plant Science. - : Frontiers Media SA. - 1664-462X. ; 11
-
Tidskriftsartikel (refereegranskat)abstract
- There is an urgent demand for low-arsenic rice in the global market, particularly for consumption by small children. Soils in Uppsala, Sweden, contain low concentrations of arsenic (As). We hypothesize that if certain japonica paddy rice varieties can adapt to the cold climate and long day length in Uppsala and produce normal grains, such a variety could be used for organic production of low-arsenic rice for safe rice consumption. A japonica paddy rice variety, "Heijing 5," can be cultivated in Uppsala, Sweden, after several years' adaptation, provided that the rice plants are kept under a simple plastic cover when the temperature is below 10 degrees C. Uppsala-adapted "Heijing 5" has a low concentration of 0.1 mg per kg and high protein content of 12.6% per dry weight in brown rice grain, meaning that it thus complies with all dietary requirements determined by the EU and other countries for small children. The high protein content is particularly good for small children in terms of nutrition. Theoretically, Uppsala-adapted "Heijing 5" can produce a yield of around 5100 kg per ha, and it has a potential for organic production. In addition, we speculate that cultivation of paddy rice can remove nitrogen and phosphorus from Swedish river water and reduce nutrient loads to the Baltic Sea and associated algae blooms.
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| 9. |
- Hu, Jia, et al.
(författare)
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A low-methane rice with high-yield potential realized via optimized carbon partitioning
- 2024
-
Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 920
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Tidskriftsartikel (refereegranskat)abstract
- Global rice cultivation significantly contributes to anthropogenic methane emissions. The methane emissions are caused by methane-producing microorganisms (methanogenic archaea) that are favoured by the anoxic conditions of paddy soils and small carbon molecules released from rice roots. However, different rice cultivars are associated with differences in methane emission rates suggesting that there is a considerable natural variation in this trait. Starting from the hypothesis that sugar allocation within a plant is an important factor influencing both yields and methane emissions, the aim of this study was to produce high-yielding rice lines associated with low methane emissions. In this study, the offspring (here termed progeny lines) of crosses between a newly characterized low-methane rice variety, Heijing 5, and three high-yielding elite varieties, Xiushui, Huayu and Jiahua, were selected for combined low-methane and high-yield properties. Analyses of total organic carbon and carbohydrates showed that the progeny lines stored more carbon in above-ground tissues than the maternal elite varieties. Also, metabolomic analysis of rhizospheric soil surrounding the progeny lines showed reduced levels of glucose and other carbohydrates. The carbon allocation, from roots to shoots, was further supported by a transcriptome analysis using massively parallel sequencing of mRNAs that demonstrated elevated expression of the sugar transporters SUT-C and SWEET in the progeny lines as compared to the parental varieties. Furthermore, measurement of methane emissions from plants, grown in greenhouse as well as outdoor rice paddies, showed a reduction in methane emissions by approximately 70 % in the progeny lines compared to the maternal elite varieties. Taken together, we report here on three independent low -methane -emission rice lines with high yield potential. We also provide a first molecular characterisation of the progeny lines that can serve as a foundation for further studies of candidate genes involved in sugar allocation and reduced methane emissions from rice cultivation.
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| 10. |
- Hu, Jia, et al.
(författare)
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Characterisation of a low methane emission rice cultivar suitable for cultivation in high latitude light and temperature conditions
- 2023
-
Ingår i: Environmental Science and Pollution Research. - 0944-1344 .- 1614-7499. ; 30, s. 92950-92962
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Tidskriftsartikel (refereegranskat)abstract
- Rice cultivation on paddy soil is commonly associated with emissions of methane, a greenhouse gas, but rice varieties may differ in their actual level of emissions. This study analysed methane emissions associated with 22 distinct rice genotypes, using gas chromatography, and identified the cultivar Heijing 5 from northern China as a potential low-methane rice variety. To confirm this and to examine whether Heijing 5 can perform similarly at higher latitudes, Heijing 5 was cultivated in field trials in China (lat. 32° N) and Sweden (lat. 59° N) where (i) methane emissions were measured, (ii) methanogen abundance in the rhizosphere was determined using quantitative PCR, and (iii) the concentrations of nutrients in water and of heavy metals in rice grain and paddy soil were analysed. The results demonstrated that the low-methane rice cultivar Heijing 5 can successfully complete an entire growth period at high-latitude locations such as central Sweden. Massively parallel sequencing of mRNAs identified candidate genes involved in day length and cold acclimatisation. Cultivation of Heijing 5 in central Sweden was also associated with relatively low heavy metal accumulation in rice grains and lowered nutrient losses to neighbouring water bodies.
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| 11. |
- Jansson, Christer, et al.
(författare)
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Cassava, a potential biofuel crop in (the) People's Republic of China
- 2009
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Ingår i: Applied Energy. - : Elsevier BV. - 0306-2619 .- 1872-9118. ; 86, s. S95-S99
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Tidskriftsartikel (refereegranskat)abstract
- Cassava ranks fifth among crops in global starch production. It is used as staple food in many tropical countries of Africa, Asia and Latin America. In (the) People's Republic of China, although not yet a staple food, cassava is of major economic importance for starch for a large area of southern (the) PRC, especially in the provinces of Guangdong, Guanxi, Yunnan and Hainan. Recently, cassava-derived bioethanol production has been increasing due to its economic benefits compared to other bioethanol-producing crops in the country. We discuss here the possible potentials of cassava for bioethanol production
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| 12. |
- Jin, Yunkai, et al.
(författare)
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Improved bioenergy value of residual rice straw by increased lipid levels from upregulation of fatty acid biosynthesis
- 2023
-
Ingår i: Biotechnology for Biofuels and Bioproducts. - 2731-3654. ; 16
-
Tidskriftsartikel (refereegranskat)abstract
- BackgroundRice (Oryza sativa) straw is a common waste product that represents a considerable amount of bound energy. This energy can be used for biogas production, but the rate and level of methane produced from rice straw is still low. To investigate the potential for an increased biogas production from rice straw, we have here utilized WRINKLED1 (WRI1), a plant AP2/ERF transcription factor, to increase triacylglycerol (TAG) biosynthesis in rice plants. Two forms of Arabidopsis thaliana WRI1 were evaluated by transient expression and stable transformation of rice plants, and transgenic plants were analyzed both for TAG levels and biogas production from straw.ResultsBoth full-length AtWRI1, and a truncated form lacking the initial 141 amino acids (including the N-terminal AP2 domain), increased fatty acid and TAG levels in vegetative and reproductive tissues of Indica rice. The stimulatory effect of the truncated AtWRI1 was significantly lower than that of the full-length protein, suggesting a role for the deleted AP2 domain in WRI1 activity. Full-length AtWRI1 increased TAG levels also in Japonica rice, indicating a conserved effect of WRI1 in rice lipid biosynthesis. The bio-methane production from rice straw was 20% higher in transformants than in the wild type. Moreover, a higher producing rate and final yield of methane was obtained for rice straw compared with rice husks, suggesting positive links between methane production and a high amount of fatty acids.ConclusionsOur results suggest that heterologous WRI1 expression in transgenic plants can be used to improve the metabolic potential for bioenergy purposes, in particular methane production.
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| 13. |
- Jin, Y. K., et al.
(författare)
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A Dual-Promoter Gene Orchestrates the Sucrose-Coordinated Synthesis of Starch and Fructan in Barley
- 2017
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Ingår i: Molecular Plant. - : Elsevier BV. - 1674-2052 .- 1752-9867. ; 10:12, s. 1556-1570
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Tidskriftsartikel (refereegranskat)abstract
- Sequential carbohydrate synthesis is important for plant survival because it guarantees energy supplies for growth and development during plant ontogeny and reproduction. Starch and fructan are two important carbohydrates in many flowering plants and in human diets. Understanding this coordinated starch and fructan synthesis and unraveling how plants allocate photosynthates and prioritize different carbohydrate synthesis for survival could lead to improvements to cereals in agriculture for the purposes of greater food security and production quality. Here, we report a system from a single gene in barley employing two alternative promoters, one intronic/exonic, to generate two sequence-overlapping but functionally opposing transcription factors, in sensing sucrose, potentially via sucrose/glucose/fructose/trehalose 6-phosphate signaling. The system employs an autoregulatory mechanism in perceiving a sucrose-controlled trans activity on one promoter and orchestrating the coordinated starch and fructan synthesis by competitive transcription factor binding on the other promoter. As a case in point for the physiological roles of the system, we have demonstrated that this multitasking system can be exploited in breeding barley with tailored amounts of fructan to produce healthy food ingredients. The identification of an intron/exon-spanning promoter in a hosting gene, resulting in proteins with distinct functions, adds to the complexity of plant genomes. ERYSTWYTH, WALES, V123, P453
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| 14. |
- Jin, Yunkai, et al.
(författare)
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New Energy Crops for Biofuel Production
- 2015
-
Ingår i: Handbook of clean energy systems. - Chichester, UK : John Wiley & Sons, Ltd. - 9781118388587 ; , s. 49-62
-
Bokkapitel (refereegranskat)
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| 15. |
- Jin, Yunkai, et al.
(författare)
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T-6b allocates more assimilation product for oil synthesis and less for polysaccharide synthesis during the seed development of Arabidopsis thaliana
- 2017
-
Ingår i: Biotechnology for Biofuels. - : Springer Science and Business Media LLC. - 1754-6834. ; 10
-
Tidskriftsartikel (refereegranskat)abstract
- Background: As an Agrobacterium tumefaciens T-DNA oncogene, T-6b induces the development of tumors and the enation syndrome in vegetative tissues of transgenic plants. Most of these effects are related to increases in soluble sugar contents. To verify the potential roles of T-6b in the distribution of carbon in developing seeds, not in vegetative tissues, we fused an endosperm-specific promoter to the T-6b gene for expression in transgenic Arabidopsis thaliana plants.Results: The expression of T-6b in reproductive organs did not induce the development of the enation syndrome, and moreover, promoted endosperm expansion, which increased the total seed biomass by more than 10%. Additionally, T-6b also increased oil content in mature seeds by more than 10% accompanied with the decrease of starch and mucilage content at the same time.Conclusions: T-6b enhances seed biomass and helps oil biosynthesis but not polysaccharides in reproductive organs without disturbing vegetative growth and development. Our findings suggest T-6b may be very useful for increasing oil production in biodiesel plants.
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| 16. |
- Källman, Anna, et al.
(författare)
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Starch structure in developing barley endosperm
- 2015
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Ingår i: International Journal of Biological Macromolecules. - : Elsevier BV. - 0141-8130 .- 1879-0003. ; 81, s. 730-735
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Tidskriftsartikel (refereegranskat)abstract
- Barley spikes of the cultivars/breeding lines Gustav, Karmose and SLU 7 were harvested at 9, 12 and 24 days after flowering in order to study starch structure in developing barley endosperm. Kernel dry weight, starch content and amylose content increased during development. Structural analysis was performed on whole starch and included the chain-length distribution of the whole starches and their beta-limit dextrins. Karmose, possessing the amo1 mutation, had higher amylose content and a lower proportion of long chains (DP >= 38) in the amylopectin component than SLU 7 and Gustay. Structural differences during endosperm development were seen as a decrease in molar proportion of chains of DP 22-37 in whole starch. In beta-limit dextrins, the proportion of B-fp-chains (DP 4-7) increased and the proportion of BSmajor-chains (DP 15-27) decreased during development, suggesting more frequent activity of starch branching enzymes at later stages of maturation, resulting in amylopectin with denser structure. (C) 2015 Elsevier B.V. All rights reserved.
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| 17. |
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| 18. |
- Mutisya, Joel, et al.
(författare)
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Diurnal oscillation of SBE expression in sorghum endosperm
- 2009
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Ingår i: Journal of plant physiology (Print). - : Elsevier BV. - 0176-1617 .- 1618-1328. ; 166:4, s. 428-434
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Tidskriftsartikel (refereegranskat)abstract
- Summary Spatial and temporal expression patterns of the sorghum SBEI, SBEIIA and SBEIIB genes, encoding, respectively, starch branching enzyme (SBE) I, IIA and IIB, in the developing endosperm of sorghum (Sorghum bicolor) were studied. Full-length genomic and cDNA clones for sorghum were cloned, and the SBEIIA cDNA was used together with gene-specific probes for sorghum SBEIIB and SBEI. In contrast to sorghum SBEIIB, which was expressed primarily in endosperm and embryo, SBEIIA was also expressed in vegetative tissues. All three genes shared a similar temporal expression profile during endosperm development, with a maximum activity at 15–24 d after pollination. This differed from barley and maize, in which SBEI gene activity showed a significantly later onset compared to that of SBEIIA and SBEIIB. Expression of the three SBE genes in the sorghum endosperm exhibited a diurnal rhythm during a 24-h cycle.
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| 19. |
- Mutisya, Joel, et al.
(författare)
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Starch branching enzymes in sorghum (Sorghum bicolor) and barley (Hordeum vulgare) : Comparative analyses of enzyme structure and gene expression
- 2003
-
Ingår i: Journal of plant physiology (Print). - : Elsevier BV. - 0176-1617 .- 1618-1328. ; 160:8, s. 921-930
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Tidskriftsartikel (refereegranskat)abstract
- Summary A genomic clone for starch branching enzyme (SBE) IIb was isolated from a sorghum bacterial artificial chromosome (BAC) library. The promoter and 5′ flanking sequence, the first four exons and introns as well as the last exon and the 3′ untranslated region were sequenced. The tentative transcription start site of sorghum sbeIIb was mapped based on alignment with the maize sbeIIb gene. The exon-intron structure of the 5′ portion of sorghum sbeIIb was similar to that of maize sbeIIb but differed from that of barley sbeIIb. Specifically, the intronic Bbl element involved in the endosperm specific expression of barley sbeIIb was lacking in the sorghum gene. A cDNA clone for sorghum sbeIIb was reverse PCR amplified and found to encode an 803 amino acids long protein. The amino acid sequence of sorghum SBEIIb was compared to that of sorghum SBEI and corresponding enzymes in barley. The overall identity in amino acid sequence was 54 percnt; in the central portion of the enzymes. A major difference between the SBEII and SBEI isoforms was a 67 amino acids-long C-terminal extension in the SBEIs. The spatial and temporal expression patterns of sorghum sbeIIb was determined and compared with those of the sorghum gene for SBEI and the barley genes for SBEIIB and SBEI. All four genes exhibited a seed specific expression. However, while barley sbeIIb and sbeI transcripts were detected exclusively in the endosperm, the sorghum genes were expressed also in the embryo. The activity of sorghum sbeIIb and sbeI exhibited a late onset, with a peak of transcription at around 22 days after pollination. This is similar to the pattern of barley sbeI but different from that of barley sbeIIb, which showed a peak of transcription at 12 days after pollination.
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| 20. |
- Mutisya, Joel, et al.
(författare)
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Transcriptional regulation of the sbeIIb genes in sorghum (Sorghum bicolor) and barley (Hordeum vulgare) : Importance of the barley sbeIIb second intron
- 2006
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Ingår i: Journal of plant physiology (Print). - : Elsevier BV. - 0176-1617 .- 1618-1328. ; 163:7, s. 770-780
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Tidskriftsartikel (refereegranskat)abstract
- Summary The transcriptional activity of the sorghum sbeIIb gene, encoding starch branching enzyme IIb, is seed specific, with expression in both the endosperm and the embryo. In comparison, expression of barley sbeIIb is confined to the endosperm, whereas that of barley sbeIIa occurs in endosperm, embryonic and vegetative tissues. It has been suggested that the second intron of barley sbeIIb may be instrumental in conferring endosperm-specific expression. Therefore, to further investigate the regulatory mechanisms of barley and sorghum sbe, we examined the tissue-specific activity of the sorghum sbe promoter in transient assays of green fluorescent protein (gfp) reporter constructs. We found that, when linked to the barley sbeIIb second intron, the sorghum sbeIIb promoter could not drive gfp transcription in sorghum or barley embryonic cells. Similar results were obtained for the barley sbeIIa promoter. Database searches showed that sequences homologous to the barley sbeIIb intron also exist in introns and flanking regions of some other grass genes. Deletion mutagenesis of the sorghum sbeIIb promoter identified the minimal promoters required for high- and low-level expression, respectively, but did not reveal any putative promoter elements crucial for expression. A sequence with similarity to the SURE element, implicated in sugar signaling, was located in the distal promoter region of sorghum sbeIIb, upstream of the minimal promoters. SURE elements are present in the proximal promoter regions of the sugar-regulated barley iso1 gene, and barley sbeIIb. In keeping in line with these observations, RNA-gel blot analyses demonstrated that expression of barley sbeIIb was sugar inducible, whereas that of sorghum sbeIIb was not.
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| 21. |
- Nalawade, Satish, et al.
(författare)
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Development of an efficient tissue culture after crossing (TCC) system for transgenic improvement of barley as a bioenergy crop
- 2012
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Ingår i: Applied Energy. - : Elsevier BV. - 0306-2619 .- 1872-9118. ; 91, s. 405-411
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Tidskriftsartikel (refereegranskat)abstract
- We have developed a protocol for rapid generation of barley plants with introduced genes by employing techniques of tissue culture, plant regeneration and crossing. Compared to conventional protocols, the time between pollination of To plants and identification of phenotypic expression in the T(1) generation is reduced from around 17-9 weeks. All of the selected candidates after the tissue culture screening exhibited phenotypic expression. Furthermore, by utilizing ordinary pollen crossing, we demonstrated a route for introduction of genes to a recalcitrant barley elite cultivar. This Tissue Culture after Crossing (TCC) procedure significantly enhances the prospects for producing transgenic barley lines from desirable germplasm. We suggest that the TCC method will contribute to improve barley as a promising bioenergy crop. (C) 2011 Elsevier Ltd. All rights reserved.
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| 22. |
- Su, Jun, et al.
(författare)
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Expression of barley SUSIBA2 transcription factor yields high-starch low-methane rice
- 2015
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 523, s. 602-606
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Tidskriftsartikel (refereegranskat)abstract
- Atmospheric methane is the second most important greenhouse gas after carbon dioxide, and is responsible for about 20% of the global warming effect since pre-industrial times(1,2). Rice paddies are the largest anthropogenic methane source and produce 7-17% of atmospheric methane(2,3). Warm waterlogged soil and exuded nutrients from rice roots provide ideal conditions for methanogenesis in paddies with annual methane emissions of 25-100-million tonnes(3,4). This scenario will be exacerbated by an expansion in rice cultivation needed to meet the escalating demand for food in the coming decades(4). There is an urgent need to establish sustainable technologies for increasing rice production while reducing methane fluxes from rice paddies. However, ongoing efforts for methane mitigation in rice paddies are mainly based on farming practices and measures that are difficult to implement(5). Despite proposed strategies to increase rice productivity and reduce methane emissions(4,6), no high-starch low-methane-emission rice has been developed. Here we show that the addition of a single transcription factor gene, barley SUSIBA2 (refs 7, 8), conferred a shift of carbon flux to SUSIBA2 rice, favouring the allocation of photo-synthates to aboveground biomass over allocation to roots. The altered allocation resulted in an increased biomass and starch content in the seeds and stems, and suppressed methanogenesis, possibly through a reduction in root exudates. Three-year field trials in China demonstrated that the cultivation of SUSIBA2 rice was associated with a significant reduction in methane emissions and a decrease in rhizospheric methanogen levels. SUSIBA2 rice offers a sustainable means of providing increased starch content for food production while reducing greenhouse gas emissions from rice cultivation. Approaches to increase rice productivity and reduce methane emissions as seen in SUSIBA2 rice may be particularly beneficial in a future climate with rising temperatures resulting in increased methane emissions from paddies(9,10).
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| 23. |
- Sun, Chuanxin
(författare)
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A Novel Cuticular Protein-like Cpr21L Is Essential for Nymph Survival and Male Fecundity in the Brown Planthopper
- 2023
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Ingår i: International Journal of Molecular Sciences. - : MDPI AG. - 1661-6596 .- 1422-0067. ; 24
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Tidskriftsartikel (refereegranskat)abstract
- Cuticular proteins (CPs) are a large family and perform a variety of functions. However, the physiological roles of cuticle protein 21-like (Cpr21L) in the brown planthopper (Nilaparvata lugens, BPH), one of the most destructive insect pests of rice, are largely unclear. In this study, Cpr21L was revealed to be expressed in both BPH nymphs and adults, and the mRNA expression level was much higher in male adults than female adults. Spatially, the expression of Cpr21L in the testis was higher than in the ovary. The RNA interference (RNAi) of Cpr21L seriously decreased nymph survival, and no individual survived 8 days post-dsCpr21L injection. The RNAi of Cpr21L in adults also decreased the fertility of males, especially in the dsCpr21L male x dsGFP female group. The average number of eggs laid by one female in this group significantly decreased by 50.1%, and the eggs' hatchability decreased from 76.5% to 23.8% compared with the control (dsGFP male x dsGFP female). Furthermore, observations under a stereomicroscope showed that the RNAi of Cpr21L severely impaired the development of the testes. Therefore, Cpr21L is essential for the nymphal survival and male fecundity of BPH, thus providing a possible target for pest control.
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| 24. |
- Sun, Chuanxin, et al.
(författare)
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A Novel WRKY Transcription Factor, SUSIBA2, Participates in Sugar Signaling in Barley by Binding to the Sugar-Responsive Elements of the iso1 Promoter
- 2003
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Ingår i: The Plant Cell. ; 15:9, s. 2076-2092
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Tidskriftsartikel (refereegranskat)abstract
- SURE (sugar responsive) is a cis element in plant sugar signaling. The SURE element was reported first for potato, in which it confers sugar responsiveness to the patatin promoter. A SURE binding transcription factor has not been isolated. We have isolated a transcription factor cDNA from barley and purified the corresponding protein. The transcription factor, SUSIBA2 (sugar signaling in barley), belongs to the WRKY proteins and was shown to bind to SURE and W-box elements but not to the SP8a element in the iso1 promoter. Nuclear localization of SUSIBA2 was demonstrated in a transient assay system with a SUSIBA2:green fluorescent protein fusion protein. Exploiting the novel transcription factor oligodeoxynucleotide decoy strategy with transformed barley endosperm provided experimental evidence for the importance of the SURE elements in iso1 transcription. Antibodies against SUSIBA2 were produced, and the expression pattern for susiba2 was determined at the RNA and protein levels. It was found that susiba2 is expressed in endosperm but not in leaves. Transcription of susiba2 is sugar inducible, and ectopic susiba2 expression was obtained in sugar-treated leaves. Likewise, binding to SURE elements was observed for nuclear extracts from sugar-treated but not from control barley leaves. The temporal expression of susiba2 in barley endosperm followed that of iso1 and endogenous sucrose levels, with a peak at similar to12 days after pollination. Our data indicate that SUSIBA2 binds to the SURE elements in the barley iso1 promoter as an activator. Furthermore, they show that SUSIBA2 is a regulatory transcription factor in starch synthesis and demonstrate the involvement of a WRKY protein in carbohydrate anabolism. Orthologs to SUSIBA2 were isolated from rice and wheat endosperm.; SURE (sugar responsive) is a cis element in plant sugar signaling. The SURE element was reported first for potato, in which it confers sugar responsiveness to the patatin promoter. A SURE binding transcription factor has not been isolated. We have isolated a transcription factor cDNA from barley and purified the corresponding protein. The transcription factor, SUSIBA2 (sugar signaling in barley), belongs to the WRKY proteins and was shown to bind to SURE and W-box elements but not to the SP8a element in the iso1 promoter. Nuclear localization of SUSIBA2 was demonstrated in a transient assay system with a SUSIBA2:green fluorescent protein fusion protein. Exploiting the novel transcription factor oligodeoxynucleotide decoy strategy with transformed barley endosperm provided experimental evidence for the importance of the SURE elements in iso1 transcription. Antibodies against SUSIBA2 were produced, and the expression pattern for susiba2 was determined at the RNA and protein levels. It was found that susiba2 is expressed in endosperm but not in leaves. Transcription of susiba2 is sugar inducible, and ectopic susiba2 expression was obtained in sugar-treated leaves. Likewise, binding to SURE elements was observed for nuclear extracts from sugar-treated but not from control barley leaves. The temporal expression of susiba2 in barley endosperm followed that of iso1 and endogenous sucrose levels, with a peak at approximately 12 days after pollination. Our data indicate that SUSIBA2 binds to the SURE elements in the barley iso1 promoter as an activator. Furthermore, they show that SUSIBA2 is a regulatory transcription factor in starch synthesis and demonstrate the involvement of a WRKY protein in carbohydrate anabolism. Orthologs to SUSIBA2 were isolated from rice and wheat endosperm.; SURE (sugar responsive) is a cis element in plant sugar signaling. The SURE element was reported first for potato, in which it confers sugar responsiveness to the patatin promoter. A SURE binding transcription factor has not been isolated. We have isolated a transcription factor cDNA from barley and purified the corresponding protein. The transcription factor, SUSIBA2 (sugar signaling in barley), belongs to the WRKY proteins and was shown to bind to SURE and W-box elements but not to the SP8a element in the iso1 promoter. Nuclear localization of SUSIBA2 was demonstrated in a transient assay system with a SUSIBA2:green fluorescent protein fusion protein. Exploiting the novel transcription factor oligodeoxynucleotide decoy strategy with transformed barley endosperm provided experimental evidence for the importance of the SURE elements in iso1 transcription. Antibodies against SUSIBA2 were produced, and the expression pattern for susiba2 was determined at the RNA and protein levels. It was found that susiba2 is expressed in endosperm but not in leaves. Transcription of susiba2 is sugar inducible, and ectopic susiba2 expression was obtained in sugar-treated leaves. Likewise, binding to SURE elements was observed for nuclear extracts from sugar-treated but not from control barley leaves. The temporal expression of susiba2 in barley endosperm followed that of iso1 and endogenous sucrose levels, with a peak at similar to 12 days after pollination. Our data indicate that SUSIBA2 binds to the SURE elements in the barley iso1 promoter as an activator. Furthermore, they show that SUSIBA2 is a regulatory transcription factor in starch synthesis and demonstrate the involvement of a WRKY protein in carbohydrate anabolism. Orthologs to SUSIBA2 were isolated from rice and wheat endosperm.; SURE (sugar responsive) is a cis element in plant sugar signaling. The SURE element was reported first for potato, in which it confers sugar responsiveness to the patatin promoter. A SURE binding transcription factor has not been isolated. We have isolated a transcription factor cDNA from barley and purified the corresponding protein. The transcription factor, SUSIBA2 (sugar signaling in barley), belongs to the WRKY proteins and was shown to bind to SURE and W-box elements but not to the SP8a element in the iso1 promoter. Nuclear localization of SUSIBA2 was demonstrated in a transient assay system with a SUSIBA2:green fluorescent protein fusion protein. Exploiting the novel transcription factor oligodeoxynucleotide decoy strategy with transformed barley endosperm provided experimental evidence for the importance of the SURE elements in iso1 transcription. Antibodies against SUSIBA2 were produced, and the expression pattern for susiba2 was determined at the RNA and protein levels. It was found that susiba2 is expressed in endosperm but not in leaves. Transcription of susiba2 is sugar inducible, and ectopic susiba2 expression was obtained in sugar-treated leaves. Likewise, binding to SURE elements was observed for nuclear extracts from sugar-treated but not from control barley leaves. The temporal expression of susiba2 in barley endosperm followed that of iso1 and endogenous sucrose levels, with a peak at ∌12 days after pollination. Our data indicate that SUSIBA2 binds to the SURE elements in the barley iso1 promoter as an activator. Furthermore, they show that SUSIBA2 is a regulatory transcription factor in starch synthesis and demonstrate the involvement of a WRKY protein in carbohydrate anabolism. Orthologs to SUSIBA2 were isolated from rice and wheat endosperm.
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| 25. |
- Sun, Chuanxin
(författare)
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A Rapid and Sensitive Europium Nanoparticle-Based Lateral Flow Immunoassay Combined with Recombinase Polymerase Amplification for Simultaneous Detection of Three Food-Borne Pathogens
- 2021
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Ingår i: International journal of environmental research and public health. - : MDPI AG. - 1661-7827 .- 1660-4601. ; 18
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Tidskriftsartikel (refereegranskat)abstract
- Food-borne pathogens have become an important public threat to human health. There are many kinds of pathogenic bacteria in food consumed daily. A rapid and sensitive testing method for multiple food-borne pathogens is essential. Europium nanoparticles (EuNPs) are used as fluorescent probes in lateral flow immunoassays (LFIAs) to improve sensitivity. Here, recombinase polymerase amplification (RPA) combined with fluorescent LFIA was established for the simultaneous and quantitative detection of Listeria monocytogenes, Vibrio parahaemolyticus, and Escherichia coli O157:H7. In this work, the entire experimental process could be completed in 20 min at 37 degrees C. The limits of detection (LODs) of EuNP-based LFIA-RPA were 9.0 colony-forming units (CFU)/mL for Listeria monocytogenes, 7.0 CFU/mL for Vibrio parahaemolyticus, and 4.0 CFU/mL for Escherichia coli O157:H7. No cross-reaction could be observed in 22 bacterial strains. The fluorescent LFIA-RPA assay exhibits high sensitivity and good specificity. Moreover, the average recovery of the three food-borne pathogens spiked in food samples was 90.9-114.2%. The experiments indicate the accuracy and reliability of the multiple fluorescent test strips. Our developed EuNP-based LFIA-RPA assay is a promising analytical tool for the rapid and simultaneous detection of multiple low concentrations of food-borne pathogens.
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| 26. |
- Sun, Chuanxin
(författare)
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A simple and efficient method for potential point-of-care diagnosis of human papillomavirus genotypes: combination of isothermal recombinase polymerase amplification with lateral flow dipstick and reverse dot blot
- 2019
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Ingår i: Analytical and Bioanalytical Chemistry. - : Springer Science and Business Media LLC. - 1618-2642 .- 1618-2650. ; 411, s. 7451-7460
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Tidskriftsartikel (refereegranskat)abstract
- Cervical cancer is the second most common cancer in the world's woman population with a high incidence in developing countries where diagnostic conditions for the cancer are poor. The main culprit causing the cancer is the human papillomavirus (HPV). HPV is divided into three major groups, i.e., high-risk (HR) group, probable high-risk (pHR) group, and low-risk (LR) group according to their potential of causing cervical cancer. Therefore, developing a sensitive, reliable, and cost-effective point-of-care diagnostic method for the virus genotypes in developing countries even worldwide is of high importance for the cancer prevention and control strategies. Here we present a combined method of isothermal recombinase polymerase amplification (RPA), lateral flow dipstick (LFD), and reverse dot blot (RDB), in quick point-of-care identification of HPV genotypes. The combined method is highly specific to HPV when the conserved L1 genes are used as targeted genes for amplification. The method can be used in identification of HPV genotypes at point-of-care within 1 h with a sensitivity of low to 100 fg of the virus genomic DNA. We have demonstrated that it is an excellent diagnostic point-of-care assay in monitoring the disease without time-consuming and expensive procedures and devices.
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| 27. |
- Sun, Chuanxin
(författare)
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Carboxyl-Functionalized, Europium Nanoparticle-Based Fluorescent Immunochromatographic Assay for Sensitive Detection of Citrinin in Monascus Fermented Food
- 2019
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Ingår i: Toxins. - : MDPI AG. - 2072-6651. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- A fluorescent immunochromatographic test strip (FICTS) based on the use of europium nanoparticles (EuNPs) was developed and applied to detect citrinin (CIT) in Monascus fermented food. The sensitivity of the immunoassay to detect CIT was greatly improved by the use of a specific monoclonal antibody to attach EuNPs to form a probe. Under optimum conditions, the visual detection limit was 2.5 ng/mL, and the detection limit of the instrument was 0.05 ng/mL. According to the results, the IC50 was 0.4 ng/mL. Matrix interference from various Monascus fermented foods was investigated in food sample detection. The immunosensor also demonstrated high recoveries (86.8-113.0%) and low relative standard deviations (RSDs) (1.8-15.3%) when testing spiked Monascus fermented food. The detection results of this method showed a good correlation (R-2 > 0.98) with high-performance liquid chromatography (HPLC). The results showed that the FICTS method could be used as a rapid, sensitive method to detect CIT in Monascus fermented food.
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| 28. |
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| 29. |
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| 30. |
- Sun, Chuanxin
(författare)
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Dual fluorescent immunochromatographic assay for simultaneous quantitative detection of citrinin and zearalenone in corn samples
- 2021
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Ingår i: Food Chemistry. - : Elsevier BV. - 0308-8146 .- 1873-7072. ; 336
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Tidskriftsartikel (refereegranskat)abstract
- The presence of multiple mycotoxins in the agricultural products poses a serious threat to the health of humans and animals. Citrinin (CIT) causes slow growth in animals and damages the kidney function. Zearalenone (ZEN) causes chronic poisoning, abnormal functioning and even death in animals. Herein, a dual fluorescent immunochromatographic assay (DF-ICA) based on europium nanoparticles (EuNPs) was developed for the simultaneous detection of CIT and ZEN in the corn samples. After optimization, the limits of detection (LODs), IC50 and average recoveries for the simultaneous determination of CIT and ZEN were 0.06 and 0.11 ng/mL, 0.35 and 0.76 ng/mL, from 86.3% to 111.6% and from 86.6% to 114.4%, respectively. Moreover, the DF-ICA was validated by high performance liquid chromatography (HPLC) analyses, and a satisfactory consistency was obtained. In brief, this work demonstrates the feasibility of DF-ICA for simultaneous monitoring of CIT and ZEN in the corn samples.
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| 31. |
- Sun, Chuanxin
(författare)
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Employing DNA binding dye to improve detection of Enterocytozoon hepatopenaei in real-time LAMP
- 2019
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Enterocytozoon hepatopenaei (EHP) is a pathogen in the pancreatic tissue of prawn, as reported in recent years. Enterosporidiosis caused by EHP in Penaeus genus is spreading widely, which seriously threatens the sustainable development of shrimp aquaculture in the world. Empolying the DNA binding dye of SYTO-16, a real-time quantitative loop-mediated isothermal amplification (LAMP) method has been established herein to detect EHP. The primer sequences used in the LAMP reaction were according to the SSU rRNA gene. The LAMP assay has reached a sensitivity of 10(1) copies/mu L and no cross-reaction with other aquatic pathogens. Compared with normal PCR, the efficiency of the LAMP technique is more sensitive, which has a shorter detection time. The use of fluorescent nucleic acid dye (SYTO-16) reveals a more satisfactory performance relative to calcein. The quantitative LAMP assay can be considered as a valid tool for rapid detection of microsporidian in prawns. Our study provides a scientific basis to follow the effect of the pathogen infection on growth of cultured penaeid shrimp.
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| 32. |
- Sun, Chuanxin
(författare)
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Functional Up-Conversion Nanoparticle-Based Immunochromatography Assay for Simultaneous and Sensitive Detection of Residues of Four Tetracycline Antibiotics in Milk
- 2020
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Ingår i: Frontiers in Chemistry. - : Frontiers Media SA. - 2296-2646. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- An ultrahigh-sensitivity lateral flow immunochromatography (LFIC) assay based on up-converting nanoparticles (UCNPs) was developed to carry out a multi-residue detection of tetracycline in milk. The sensitivity of the immunoassay was greatly improved by the use of a broad-spectrum monoclonal antibody attached to UCNPs to form a signal probe. Under the optimal conditions, the UCNP-LFIC assay enabled sensitive detection of tetracycline (TC) as well as of oxytetracycline (OTC), chlortetracycline (CTC), and doxycycline (DOX) within 10 min, withIC(50)values of 0.32, 0.32, 0.26, 0.22 ng/mL, respectively. There was no cross-reactivity with ten other antibiotics. Similarly, we evaluated the experimental results for matrix effects. Experiments involving spiking showed the four tetracycline antibiotics displaying mean recoveries ranging from 93.95 to 111.90% with relative standard deviations (RSDs) of < 9.95%. The detection results of actual samples using the developed method showed a good correlation (R-2 >= 0.98) with the results using high-performance liquid chromatography (HPLC). Thus, the assay can achieve an ultrahighly sensitive detection of antibiotics in milk, and can hence promote human health and provides promising applications in the bio-detection field.
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| 33. |
- Sun, Chuanxin
(författare)
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Multiplex Recombinase Polymerase Amplification Assay for the Simultaneous Detection of Three Foodborne Pathogens in Seafood
- 2020
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Ingår i: Foods. - : MDPI AG. - 2304-8158. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Foodborne pathogens can cause foodborne illness. In reality, one food sample may carry more than one pathogen. A rapid, sensitive, and multiple target method for bacteria detection is crucial in food safety. For the simultaneous detection of Staphylococcus aureus, Vibrio parahaemolyticus, and Salmonella Enteritidis, multi-objective recombinase polymerase amplification (RPA) combined with a lateral flow dipstick (LFD) was developed in this study. The whole process, including amplification and reading, can be completed in 15 min at 37 degrees C. The detection limits were 2.6 x 10(1) CFU/mL for Staphylococcus aureus, 7.6 x 10(1) CFU/mL for Vibrio parahaemolyticus, and 1.29 x 10(1) CFU/mL for Salmonella Enteritidis. Moreover, colored signal intensities on test lines were measured by a test strip reader to achieve quantitative detection for Staphylococcus aureus (R-2 = 0.9903), Vibrio parahaemolyticus (R-2 = 0.9928), and Salmonella Enteritidis (R-2 = 0.9945). In addition, the method demonstrated good recoveries (92.00%-107.95%) in the testing of spiked food samples. Therefore, the multiplex LFD-RPA assay is a feasible method for the rapid, sensitive, and quantitative detection of bacterial pathogens in seafood.
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| 34. |
- Sun, Chuanxin
(författare)
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Recombinase Polymerase Amplification (RPA) Combined with Lateral Flow Immunoassay for Rapid Detection of Salmonella in Food
- 2020
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Ingår i: Foods. - : MDPI AG. - 2304-8158. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Salmonella can cause serious foodborne diseases. We have developed a lateral flow immunoassay combined with recombinase polymerase amplification (LFD-RPA) for detection of Salmonella in food. The conserved fragment (fimY) was selected as the target gene. Under an optimal condition (37 degrees C, 10 min), the sensitivity was 12 colony-forming units (CFU)/mL in a pure culture. Testing with 16 non-Salmonella strains as controls revealed that LFD-RPA was specific to the fimY gene of Salmonella. The established assay could detect Salmonella at concentrations as low as 1.29 x 10(2) CFU/mL in artificially contaminated samples. This detection was at a slightly higher level than that for a pure bacterial culture. Combined with the test strip reader, the LFD-RPA is a feasible method for quantitative detection of Salmonella based on the test line intensity, which was the ratio for the test line and control line of the reflected light. The method could be a potential point-of-care test in limited resource areas and provides a new approach and technical support for the diagnosis of food safety.
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| 35. |
- Sun, Chuanxin
(författare)
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RNAi-mediated silencing of the autophagy-related gene NlATG3 inhibits survival and fecundity of the brown planthopper, Nilaparvata lugens
- 2021
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Ingår i: Pest Management Science. - : Wiley. - 1526-498X .- 1526-4998. ; 77, s. 4658-4668
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND The brown planthopper (BPH), Nilaparvata lugens, is a serious insect pest of rice. Autophagy and its related gene ATG3 play multiple roles in insects. However, information about the functions of ATG3 in BPH (NlATG3) is unavailable, and its potential as a target for pest control remains unclear. RESULTS RT-qPCR results showed a relatively low expression of NlATG3 in 1st-4th-instar nymphs, which increased through 9-day-old adults. The expression of NlATG3 increased continuously in 1-day-old through 5-day-old eggs, whereas it decreased thereafter. The mRNA level of NlATG3 was markedly higher in the ovary (1.16) and head (1.00) compared to the rest body parts of BPH adults. Injecting nymphs with dsNlATG3 at doses from 62.5 to 250 ng per insect had strong lethal effect upon them. For the 5th-instar nymphs, all individuals died within 5 days after receiving the dsNlATG3, and importantly, no individual successfully molted. Transmission electron microscopy revealed the new cuticle of nymphs injected with dsNlATG3 became loose and curved, which is clearly different from that of the control. Correspondingly, the obvious vesicles in epidermal cells disappeared after dsNlATG3-treatment. RNAi of NlATG3 significantly reduced the total number of eggs laid per female as well as the eggs' hatchability, especially in the dsNlATG3 female x dsGFP male group, whose total number of eggs laid per female largely decreased by 80.4%, and whose eggs' hatchability was significantly reduced from 95.7% to zero, when compared with the control (dsGFP female x dsGFP male). CONCLUSION NlATG3 is a promising target for developing RNAi-based insect management strategies.
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| 36. |
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| 37. |
- Sun, Chuanxin
(författare)
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The Future Crops for Biofuels
- 2011
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Ingår i: Economic Effects of Biofuel Production. - : InTech. - 9789533071787 ; , s. 25-38
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 38. |
- Sun, Xun, et al.
(författare)
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Can experiment determine the stacking fault energy of metastable alloys?
- 2021
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Ingår i: Materials & design. - : Elsevier Ltd. - 0264-1275 .- 1873-4197. ; 199
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Tidskriftsartikel (refereegranskat)abstract
- Stacking fault energy (SFE) plays an important role in deformation mechanisms and mechanical properties of face-centered cubic (fcc) metals and alloys. In many concentrated fcc alloys, the SFEs determined from density functional theory (DFT) calculations and experimental methods are found having opposite signs. Here, we show that the negative SFE by DFT reflects the thermodynamic instability of the fcc phase relative to the hexagonal close-packed one; while the experimentally determined SFEs are restricted to be positive by the models behind the indirect measurements. We argue that the common models underlying the experimental measurements of SFE fail in metastable alloys. In various concentrated solid solutions, we demonstrate that the SFEs obtained by DFT calculations correlate well with the primary deformation mechanisms observed experimentally, showing a better resolution than the experimentally measured SFEs. Furthermore, we believe that the negative SFE is important for understanding the abnormal behaviors of partial dislocations in metastable alloys under deformation. The present work advances the fundamental understanding of SFE and its relation to plastic deformations, and sheds light on future alloy design by physical metallurgy.
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| 39. |
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| 40. |
- Xie, Zhoupeng, et al.
(författare)
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A selection strategy in plant transformation based on antisense oligodeoxynucleotide inhibition
- 2014
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Ingår i: Plant Journal. - : Wiley. - 0960-7412 .- 1365-313X. ; 77, s. 954-961
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Tidskriftsartikel (refereegranskat)abstract
- Antisense oligodeoxynucleotide (asODN) inhibition was developed in the 1970s, and since then has been widely used in animal research. However, in plant biology, the method has had limited application because plant cell walls significantly block efficient uptake of asODN to plant cells. Recently, we have found that asODN uptake is enhanced in a sugar solution. The method has promise for many applications, such as a rapid alternative to time-consuming transgenic studies, and high potential for studying gene functionality in intact plants and multiple plant species, with particular advantages in evaluating the roles of multiple gene family members. Generation of transgenic plants relies on the ability to select transformed cells. This screening process is based on co-introduction of marker genes into the plant cell together with a gene of interest. Currently, the most common marker genes are those that confer antibiotic or herbicide resistance. The possibility that traits introduced by selectable marker genes in transgenic field crops may be transferred horizontally is of major public concern. Marker genes that increase use of antibiotics and herbicides may increase development of antibiotic-resistant bacterial strains or contribute to weed resistance. Here, we describe a method for selection of transformed plant cells based on asODN inhibition. The method enables selective and high-throughput screening for transformed cells without conferring new traits or functions to the transgenic plants. Due to their high binding specificity, asODNs may also find applications as plant-specific DNA herbicides.
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