| 1. |
- Sundberg, K. Å. T., et al.
(författare)
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Magnetic field oscillations at SANAE IV related to sudden increases in solar wind dynamic pressure
- 2005
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Ingår i: South African Journal of Science. - 0038-2353 .- 1996-7489. ; 101:12-nov, s. 539-543
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Tidskriftsartikel (refereegranskat)abstract
- The magnetospheric response at times when sudden increases in the solar wind dynamic pressure cause terrestrial magnetic storms has been studied with data from the pulsation magnetometer at the South African Antarctic research base, SANAE IV. For solar wind events that lead to a sudden increase in the terrestrial magnetic field at Hermanus and Kakioka, related pulsations were found in the SANAE IV data. We studied seven solar wind events of special interest between 19 February 2003 and 18 February 2004. The events can be divided into two main pulsation groups: one group had a well-defined frequency and a duration of about 15 minutes, whereas the other had a less well-defined frequency content, longer duration and exhibited large amplitude fluctuations. The analysis confirms the conclusion that the measured response time of the magnetosphere to disturbances in the solar wind is broadly consistent with the propagation speed of magneto-hydrodynamic waves driven by solar wind dynamic pressure.
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| 2. |
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| 3. |
- Alström, P., et al.
(författare)
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Morphological, vocal and genetic divergence in the Cettia acanthizoides complex (Aves: Cettiidae)
- 2007
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Ingår i: Zoological Journal of the Linnean Society. - : Oxford University Press (OUP). - 0024-4082 .- 1096-3642. ; 149:3, s. 437-452
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Tidskriftsartikel (refereegranskat)abstract
- We used morphological, vocal and molecular (one mitochondrial and two nuclear loci) data to re-evaluate the taxonomic status of the taxa acanthizoides, concolor, and brunnescens in the Cettia acanthizoides (J. Verreaux, 1871) complex. We conclude that all three are valid taxa, and that acanthizoides of China and concolor of Taiwan are best treated as conspecific, whereas brunnescens of the Himalayas is better considered as a separate species. The degree of morphological, vocal, and genetic differentiation is variably congruent among all taxa; the recently separated acanthizoides and concolor differ slightly in plumage and structure but are indistinguishable in vocalizations, whereas the earlier diverged brunnescens and acanthizoides/concolor differ only slightly more in morphology but to a much greater degree in vocalizations. We stress the essential nature of taxonomic revisions as a prerequisite for the biodiversity estimates required for conservation planning.
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| 4. |
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| 5. |
- Andersson-Gunneras, S., et al.
(författare)
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Biosynthesis of cellulose-enriched tension wood in Populus : global analysis of transcripts and metabolites identifies biochemical and developmental regulators in secondary wall biosynthesis
- 2006
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Ingår i: The Plant Journal. - Malden : Wiley-Blackwell. - 0960-7412 .- 1365-313X. ; 45:2, s. 144-165
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Tidskriftsartikel (refereegranskat)abstract
- Stems and branches of angiosperm trees form tension wood (TW) when exposed to a gravitational stimulus. One of the main characteristics of TW, which distinguishes it from normal wood, is the formation of fibers with a thick inner gelatinous cell wall layer mainly composed of crystalline cellulose. Hence TW is enriched in cellulose, and deficient in lignin and hemicelluloses. An expressed sequence tag library made from TW-forming tissues in Populus tremula (L.) x tremuloides (Michx.) and data from transcript profiling using microarray and metabolite analysis were obtained during TW formation in Populus tremula (L.) in two growing seasons. The data were examined with the aim of identifying the genes responsible for the change in carbon
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| 6. |
- Aspeborg, Henrik, et al.
(författare)
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Carbohydrate-active enzymes involved in the secondary cell wall biogenesis in hybrid aspen
- 2005
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Ingår i: Plant Physiology. - : Oxford University Press (OUP). - 0032-0889 .- 1532-2548. ; 137:3, s. 983-997
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Tidskriftsartikel (refereegranskat)abstract
- Wood formation is a fundamental biological process with significant economic interest. While lignin biosynthesis is currently relatively well understood, the pathways leading to the synthesis of the key structural carbohydrates in wood fibers remain obscure. We have used a functional genomics approach to identify enzymes involved in carbohydrate biosynthesis and remodeling during xylem development in the hybrid aspen Populus tremula x tremuloides. Microarrays containing cDNA clones from different tissue-specific libraries were hybridized with probes obtained from narrow tissue sections prepared by cryosectioning of the developing xylem. Bioinformatic analyses using the sensitive tools developed for carbohydrate-active enzymes allowed the identification of 25 xylem-specific glycosyltransferases belonging to the Carbohydrate-Active EnZYme families GT2, GT8, GT14, GT31, GT43, GT47, and GT61 and nine glycosidases (or transglycosidases) belonging to the Carbohydrate-Active EnZYme families GH9, GH10, GH16, GH17, GH19, GH28, GH35, and GH51. While no genes encoding either polysaccharide lyases or carbohydrate esterases were found among the secondary wall-specific genes, one putative O-acetyltransferase was identified. These wood-specific enzyme genes constitute a valuable resource for future development of engineered fibers with improved performance in different applications.
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| 7. |
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| 8. |
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| 9. |
- Björkner, Eva, et al.
(författare)
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Voice source differences between registers in female musical theater singers
- 2006
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Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 20:2, s. 187-197
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Tidskriftsartikel (refereegranskat)abstract
- Musical theater singing typically requires women to use two vocal registers. Our investigation considered voice source and subglottal pressure P-s characteristics of the speech pressure signal recorded for a sequence of /pae/ syllables sung at constant pitch and decreasing vocal loudness in each register by seven female musical theater singers. Ten equally spaced P-s values were selected, and the relationships between P-s and several parameters were examined; closed-quotient (Q(closed)), peak-to-peak pulse amplitude (Up-t-p), amplitude of the negative peak of the differentiated flow glottogram. ie, the maximum flow declination rate (MFDR), and the normalized amplitude quotient (NAQ) [Up-t-p/(TO*MFDR)], where TO is the fundamental period. P, was typically slightly higher in chest than in head register. As P, influences the measured glottogram parameters, these were also compared at an approximately identical P-s of 11 cm H2O. Results showed that for typical tokens, MFDR and Q(closed) were significantly greater, whereas Up-t-p and therefore NAQ were significantly lower in chest than in head.
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| 10. |
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| 11. |
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| 12. |
- Delsing, Jerker, et al.
(författare)
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Susceptibility of sensor networks to intentional electromagnetic interference
- 2006
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Ingår i: 2006 17th International Zurich Symposium on Electromagnetic Compatibility. - Piscataway, NJ : IEEE Communications Society. - 3952299030 ; , s. 172-175
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Konferensbidrag (refereegranskat)abstract
- It is reasonable to think that sensor networks might be part of society critical systems in the future. Therefor this paper discusses and shows the vulnerabilities of sensor networks to intentional electromagnetic interference (IEMI). Principle ways of sensor network IEMI is addressed and followed by a discussion on schemes for protection. Experimental results for both in-band and exband interference from low- and high- level sources is reported. It is obvious that more emphasis has to be put on sensor networks susceptibility to IEMI, and in particular more experimental data is needed.
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| 13. |
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| 14. |
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| 15. |
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| 16. |
- Geisler-Lee, Jane, et al.
(författare)
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Poplar carbohydrate-active enzymes. Gene identification and expression analyses.
- 2006
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Ingår i: Plant Physiology. - : Oxford University Press (OUP). - 0032-0889 .- 1532-2548. ; 140:3, s. 946-62
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Tidskriftsartikel (refereegranskat)abstract
- Over 1,600 genes encoding carbohydrate-active enzymes (CAZymes) in the Populus trichocarpa (Torr. & Gray) genome were identified based on sequence homology, annotated, and grouped into families of glycosyltransferases, glycoside hydrolases, carbohydrate esterases, polysaccharide lyases, and expansins. Poplar (Populus spp.) had approximately 1.6 times more CAZyme genes than Arabidopsis (Arabidopsis thaliana). Whereas most families were proportionally increased, xylan and pectin-related families were underrepresented and the GT1 family of secondary metabolite-glycosylating enzymes was overrepresented in poplar. CAZyme gene expression in poplar was analyzed using a collection of 100,000 expressed sequence tags from 17 different tissues and compared to microarray data for poplar and Arabidopsis. Expression of genes involved in pectin and hemicellulose metabolism was detected in all tissues, indicating a constant maintenance of transcripts encoding enzymes remodeling the cell wall matrix. The most abundant transcripts encoded sucrose synthases that were specifically expressed in wood-forming tissues along with cellulose synthase and homologs of KORRIGAN and ELP1. Woody tissues were the richest source of various other CAZyme transcripts, demonstrating the importance of this group of enzymes for xylogenesis. In contrast, there was little expression of genes related to starch metabolism during wood formation, consistent with the preferential flux of carbon to cell wall biosynthesis. Seasonally dormant meristems of poplar showed a high prevalence of transcripts related to starch metabolism and surprisingly retained transcripts of some cell wall synthesis enzymes. The data showed profound changes in CAZyme transcriptomes in different poplar tissues and pointed to some key differences in CAZyme genes and their regulation between herbaceous and woody plants.
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| 17. |
- Gray-Mitsumune, Madoka, et al.
(författare)
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Ectopic expression of a wood-abundant expansin PttEXPA1 promotes cell expansion in primary and secondary tissues in aspen
- 2008
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Ingår i: Plant Biotechnology Journal. - : Wiley. - 1467-7644 .- 1467-7652. ; 6:1, s. 62-72
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Tidskriftsartikel (refereegranskat)abstract
- Expansins are primary agents inducing cell wall extension, and are therefore obvious targets in biotechnological applications aimed at the modification of cell size in plants. In trees, increased fibre length is a goal of both breeding and genetic engineering programmes. We used an alpha-expansin PttEXPA1 that is highly abundant in the wood-forming tissues of hybrid aspen (Populus tremula L. x P. tremuloides Michx.) to evaluate its role in fibre elongation and wood cell development. PttEXPA1 belongs to Subfamily A of alpha-expansins that have conserved motifs at the N- and C-termini of the mature protein. When PttEXPA1 was over-expressed in aspen, an extract of the cell wall-bound proteins of the transgenic plants exhibited an increased expansin activity on cellulose-xyloglucan composites in vitro, indicating that PttEXPA1 is an active expansin. The transgenic lines exhibited increased stem internode elongation and leaf expansion, and larger cell sizes in the leaf epidermis, indicating that PttEXPA1 protein is capable of increasing the growth of these organs by enhancing cell wall expansion in planta. Wood cell development was also modified in the transgenic lines, but the effects were different for vessel elements and fibres, the two main cell types of aspen wood. PttEXPA1 stimulated fibre, but not vessel element, diameter growth, and marginally increased vessel element length, but did not affect fibre length. The observed differences in responsiveness to expansin of these cell types are discussed in the light of differences in their growth strategies and cell wall composition.
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| 18. |
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| 19. |
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| 20. |
- Gustafsson, T, et al.
(författare)
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The influence of physical training on the angiopoietin and VEGF-A systems in human skeletal muscle
- 2007
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Ingår i: Journal of applied physiology (Bethesda, Md. : 1985). - : American Physiological Society. - 8750-7587 .- 1522-1601. ; 103:3, s. 1012-1020
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Tidskriftsartikel (refereegranskat)abstract
- Eleven subjects performed one-legged exercise four times per week for 5 wk. The subjects exercised one leg for 45 min with restricted blood flow (R leg), followed by exercise with the other leg at the same absolute workload with unrestricted blood flow (UR leg). mRNA and protein expression were measured in biopsies from the vastus lateralis muscle obtained at rest before the training period, after 10 days, and after 5 wk of training, as well as 120 min after the first and last exercise bouts. Basal Ang-2 and Tie-1 mRNA levels increased in both legs with training. The Ang-2-to-Ang-1 ratio increased to a greater extent in the R leg. The changes in Ang-2 mRNA were followed by similar changes at the protein level. In the R leg, VEGF-A mRNA expression responded transiently after acute exercise both before and after the 5-wk training program. Over the course of the exercise program, there was a concurrent increase in basal VEGF-A protein and VEGFR-2 mRNA in the R leg. Ki-67 mRNA showed a greater increase in the R leg and the protein was localized to the endothelial cells. In summary, the increased translation of VEGF-A is suggested to be caused by the short mRNA burst induced by each exercise bout. The concurrent increase in the Ang-2-to-Ang-1 ratio and the VEGF-expression combined with the higher level of Ki-67 mRNA in the R leg indicate that changes in these systems are of importance also in nonpathological angiogenic condition such as voluntary exercise in humans. It further establish that hypoxia/ischemia-related metabolic perturbation is likely to be involved as stimuli in this process in human skeletal muscle.
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| 21. |
- Gustafsson, T, et al.
(författare)
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VEGF-A splice variants and related receptor expression in human skeletal muscle following submaximal exercise
- 2005
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Ingår i: Journal of applied physiology (Bethesda, Md. : 1985). - : American Physiological Society. - 8750-7587 .- 1522-1601. ; 98:6, s. 2137-2146
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Tidskriftsartikel (refereegranskat)abstract
- VEGF-A contributes to muscle tissue angiogenesis following aerobic exercise training. The temporal response of the VEGF-A isoforms and their target receptors has not been comprehensively profiled in human skeletal muscle. We combined submaximal exercise with and without reduced leg blood flow to establish whether ischemia-induced metabolic stress was an important physiological stimuli responsible for regulating the VEGF-A system in humans. Nine healthy men performed two 45-min bouts of one-leg knee-extension exercise, with and without blood flow restriction. Muscle biopsies were obtained at rest and 2 and 6 h after exercise. Expression (mRNA) of the VEGF-A splice variants and related receptors [VEGF receptor (VEGFR)-1, VEGFR-2, and neuropilin-1] was determined by using qPCR. VEGF-Atotal expression increased more robustly after exercise with reduced blood flow, and initially this principally reflected an increase in VEGF-A165. Six hours after exercise, there was a relatively greater increase in VEGF-A189, and this response was not influenced by blood flow conditions. VEGFR-1 mRNA expression increased 2 h after exercise, and neuropilin-1 expression was transiently reduced, while all three receptors increased by 6 h. There was no evidence for the expression of the inhibitory VEGF-A165B variant in human skeletal muscle. Our study, reflecting both VEGF-A ligand and receptors, implicates metabolic perturbation as a regulator of human muscle angiogenesis and demonstrates that VEGF-A splice variants are distinctly regulated. Our findings also indicate that all three receptor genes exhibit different pretranslational regulation, in response to exercise in humans.
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| 22. |
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| 23. |
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| 24. |
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| 25. |
- Kumar, Manoj, et al.
(författare)
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An update on the nomenclature for the cellulose synthase genes in Populus
- 2009
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Ingår i: Trends in Plant Science. - : Elsevier BV. - 1360-1385 .- 1878-4372. ; 14:5, s. 248-254
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Forskningsöversikt (refereegranskat)abstract
- Cellulose synthase (CesA) is a central catalyst in the generation of the plant cell wall biomass and is, therefore, the focus of intense research. Characterization of individual CesA genes from Populus species has led to the publication of several different naming conventions for CesA gene family members in this model tree. To help reduce the resulting confusion, we propose here a new phylogeny-based CesA nomenclature that aligns the Populus CesA gene family with the established Arabidopsis thaliana CesA family structure.
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| 26. |
- Nienkerke-Springer, A, et al.
(författare)
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Effects of family therapy on children's voices
- 2005
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Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 19:1, s. 103-113
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Tidskriftsartikel (refereegranskat)abstract
- The families of nine children with deviant voice qualities were selected for family treatment according to the SYGESTI model. Recordings of the children's speech were made before and after therapy. Perceptual evaluation of their voice quality showed significant improvement in various perceptual parameters after the therapy. Acoustical analysis confirmed changes of voice quality and mean fundamental frequency in speech. The therapy also was found to improve relations between family members, conflict management and other aspects of communication. The results suggest that these children's deviant voices were related to family conditions.
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| 27. |
- Nishikubo, Nobuyuki, et al.
(författare)
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Xyloglucan endo-transglycosylase (XET) functions in gelatinous layers of tension wood fibers in poplar - A glimpse into the mechanism of the balancing act of trees
- 2007
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Ingår i: Plant and Cell Physiology. - : Oxford University Press (OUP). - 0032-0781 .- 1471-9053. ; 48:6, s. 843-855
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Tidskriftsartikel (refereegranskat)abstract
- Tension wood is a specialized tissue of deciduous trees that functions in bending woody stems to optimize their position in space. Tension wood fibers that develop on one side of the stem have an increased potency to shrink compared with fibers on the opposite side, thus creating a bending moment. It is believed that the gelatinous (G) cell wall layer containing almost pure cellulose of tension wood fibers is pivotal to their shrinking. By analyzing saccharide composition and linkage in isolated G-layers of poplar, we found that they contain some matrix components in addition to cellulose, of which xyloglucan is the most abundant. Xyloglucan, xyloglucan endo-transglycosylase (XET) activity and xyloglucan endo-transglycosylase/hydrolase (XTH) gene products were detected in developing G-layers by labeling using CCRC-M1 monoclonal antibody, in situ incorporation of XXXG-SR and the polyclonal antibody to poplar PttXET16-34, respectively, indicating that xyloglucan is incorporated into the G-layer during its development. Moreover, several XTH transcripts were altered and were generally up-regulated in developing tension wood compared with normal wood. In mature G-fibers, XTH gene products were detected in the G-layers while the XET activity was evident in the adjacent S-2 wall layer. We propose that XET activity is essential for G-fiber shrinking by repairing xyloglucan cross-links between G- and S-2-layers and thus maintaining their contact. Surprisingly, XTH gene products and XET activity persisted in mature G-fibers for several years, suggesting that the enzyme functions after cell death repairing the cross-links as they are being broken during the shrinking process.
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| 28. |
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| 29. |
- Rajangam, Alex S., et al.
(författare)
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MAP20, a Microtubule-Associated Protein in the Secondary Cell Walls of Hybrid Aspen, Is a Target of the Cellulose Synthesis Inhibitor 2,6-Dichlorobenzonitrile
- 2008
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Ingår i: Plant Physiology. - : Oxford University Press (OUP). - 0032-0889 .- 1532-2548. ; 148:3, s. 1283-1294
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Tidskriftsartikel (refereegranskat)abstract
- We have identified a gene, denoted PttMAP20, which is strongly up-regulated during secondary cell wall synthesis and tightly coregulated with the secondary wall-associated CESA genes in hybrid aspen (Populus tremula x tremuloides). Immunolocalization studies with affinity-purified antibodies specific for PttMAP20 revealed that the protein is found in all cell types in developing xylem and that it is most abundant in cells forming secondary cell walls. This PttMAP20 protein sequence contains a highly conserved TPX2 domain first identified in a microtubule-associated protein (MAP) in Xenopus laevis. Overexpression of PttMAP20 in Arabidopsis (Arabidopsis thaliana) leads to helical twisting of epidermal cells, frequently associated with MAPs. In addition, a PttMAP20-yellow fluorescent protein fusion protein expressed in tobacco (Nicotiana tabacum) leaves localizes to microtubules in leaf epidermal pavement cells. Recombinant PttMAP20 expressed in Escherichia coli also binds specifically to in vitro-assembled, taxol-stabilized bovine microtubules. Finally, the herbicide 2,6-dichlorobenzonitrile, which inhibits cellulose synthesis in plants, was found to bind specifically to PttMAP20. Together with the known function of cortical microtubules in orienting cellulose microfibrils, these observations suggest that PttMAP20 has a role in cellulose biosynthesis.
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| 30. |
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| 31. |
- Rullman, E., et al.
(författare)
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A single bout of exercise activates matrix metalloproteinase in human skeletal muscle
- 2007
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Ingår i: Journal of applied physiology. - : American Physiological Society. - 8750-7587 .- 1522-1601. ; 102:6, s. 2346-2351
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Tidskriftsartikel (refereegranskat)abstract
- The aims of this study were 1) to characterize changes in matrix metalloproteinase (NIMP), endostatin, and vascular endothelial growth factor (VEGF)-A expression in skeletal muscle in response to a single bout of exercise in humans; and 2) to determine if any exchange of endostatin and VEGF-A between circulation and the exercising leg is associated with a change in the tissue expression or plasma concentration of these factors. Ten healthy males performed 65 min of cycle exercise, and muscle biopsies were obtained from the vastus lateralis muscle at rest and immediately and 120 min after exercise. In the muscle biopsies, measurements of mRNA expression levels of MMP-2, MMP-9, MMP-14, and tissue inhibitor of metalloproteinase; VEGF and endostatin protein levels; and NIMP activities were performed. Femoral arterial and venous concentrations of VEGF-A and endostatin were determined before, during, and 120 min after exercise. A single bout of exercise increased MMP-9 mRNA and activated MMP-9 protein in skeletal muscle. No measurable increase of endostatin was observed in the skeletal muscle or in plasma following exercise. A concurrent increase in skeletal muscle VEGF-A mRNA and protein levels was induced by exercise, with no signs of peripheral uptake from the circulation. However, a decrease in plasma VEGF-A concentration occurred following exercise. Thus 1) a single bout of exercise activated the MMP system without any resulting change in tissue endostatin protein levels, and 2) the increased VEGF-A protein levels are due to changes in the skeletal muscle tissue itself. Other mechanisms are responsible for the observed exercise-induced decrease in VEGF-A in plasma.
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| 32. |
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| 33. |
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| 34. |
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| 35. |
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| 36. |
- Sundberg, Martin, et al.
(författare)
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Bagged silage : Mechanical treatment applied by packing rotor improves fermentation
- 2005
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Ingår i: Silage Production and Utilisation: Proceedings of the XIVth International Silage Conference, a Satellite Workshop of the XXth International Grassland Congress, July 2005, Belfast, Northern Ireland.. - The Netherlands : Wageningen Academic Publishers. ; , s. 250-
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Konferensbidrag (refereegranskat)
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| 37. |
- Sundberg, Martin, et al.
(författare)
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Movement patterns of the C-stem femoral component: an RSA study of 33 primary total hip arthroplasties followed for two years.
- 2005
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Ingår i: Journal of Bone and Joint Surgery: British Volume. - 2044-5377. ; 87:10, s. 1352-1356
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Tidskriftsartikel (refereegranskat)abstract
- We used roentgen stereophotogrammetric analysis to follow 33 C-stem femoral components for two years after primary total hip arthroplasty. All components migrated distally and posteriorly within the cement mantle. The mean distal migration was 1.35 mm (SD 0.62) at two years and the mean posterior migration was 1.35 mm (SD 0.69) at two years. All the femoral components rotated into retroversion with a mean rotation at two years of 1.9° (SD 1.1). For all other directions, the prosthesis was stable up to two years. Compared with other tapered prostheses, the distal migration of the C-stem is the same, but posterior rotation and posterior migration are greater.
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| 38. |
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| 39. |
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| 40. |
- Takahashi Schmidt, Junko, et al.
(författare)
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KORRIGAN1 and its Aspen Homolog PttCel9A1 Decrease Cellulose Crystallinity in Arabidopsis Stems
- 2009
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Ingår i: Plant and Cell Physiology. - : Oxford University Press (OUP). - 0032-0781 .- 1471-9053. ; 50:6, s. 1099-1115
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Tidskriftsartikel (refereegranskat)abstract
- KORRIGAN1 (KOR1) is a membrane-bound cellulase implicated in cellulose biosynthesis. PttCel9A1 from hybrid aspen (Populus tremula L. tremuloides Michx.) has high sequence similarity to KOR1 and we demonstrate here that it complements kor1-1 mutants, indicating that it is a KOR1 ortholog. We investigated the function of PttCel9A1/KOR1 in Arabidopsis secondary growth using transgenic lines expressing 35S::PttCel9A1 and the KOR1 mutant line irx2-2. The presence of elevated levels of PttCel9A1/KOR1 in secondary walls of 35S::PttCel9A1 lines was confirmed by in muro visualization of cellulase activity. Compared with the wild type, 35S::PttCel9A1 lines had higher trifluoroacetic acid (TFA)-hydrolyzable glucan contents, similar Updegraff cellulose contents and lower cellulose crystallinity indices, as determined by C-13 solid-state nuclear magnetic resonance (NMR) spectroscopy. irx2-2 mutants had wild-type TFA-hydrolyzable glucan contents, but reduced Updegraff cellulose contents and higher than wild-type cellulose crystallinity indices. The data support the hypothesis that PttCel9A1/KOR1 activity is present in cell walls, where it facilitates cellulose biosynthesis in a way that increases the amount of non-crystalline cellulose.
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| 41. |
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| 42. |
- Ubeda-Tomas, Susana, et al.
(författare)
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Genomic-assisted identification of genes involved in secondary growth in Arabidopsis utilising transcript profiling of poplar wood-forming tissues
- 2007
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Ingår i: Physiologia Plantarum. - : Wiley. - 0031-9317 .- 1399-3054. ; 129:2, s. 415-428
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Tidskriftsartikel (refereegranskat)abstract
- Despite the importance of secondary growth in plants, relatively few genes regulating this process have been identified to date. By using data from detailed transcript profiling of the poplar wood-forming tissues, 150 genes that are differentially expressed within the zone of secondary growth were identified. In order to determine the possible function of these poplar genes, potential Arabidopsis thaliana orthologs were identified and gene knockout lines analysed. Three selection filters were used to identify the most likely orthologous genes using poplar and Arabidopsis sequence comparisons, expression profiling in secondary thickened Arabidopsis hypocotyls and global expression analysis of Arabidopsis tissues. Three genes encoding AtCSLA2 (At5g22740), the AtGUT1 GT47 glycosyltransferase (At1g27440) and a protein with no proposed function AtUNKA (At4g27435) were selected for further detailed analysis of their role in secondary growth in Arabidopsis. The presented genome-based approach using both poplar and Arabidopsis systems provides powerful means towards assigning biological functions to enzymes with poorly understood biochemical activity, such as AtCSLA2 and AtGUT1, as well as for proteins with no known function.
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| 43. |
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| 44. |
- Zima, T, et al.
(författare)
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Modulation of oxidative stress by alcohol
- 2005
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Ingår i: ALCOHOL-CLINICAL AND EXPERIMENTAL RESEARCH. - 0145-6008. ; 29:6, s. 1060-1065
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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