| 1. |
- Astromskas, Eimantas, et al.
(författare)
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Ends-in vs. ends-out targeted insertion mutagenesis in Saccharomyces castellii.
- 2009
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 55:3, s. 339-347
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Tidskriftsartikel (refereegranskat)abstract
- Gene replacement (knock-out) is a major tool for the analysis of gene function. However, the efficiency of correct targeting varies between species, and is dependent on the structure of the DNA construct. We analyzed the targeted insertion mutagenesis method in the budding yeast Saccharomyces castellii, phylogenetically positioned after the whole genome duplication event in the Saccharomyces lineage. We compared the targeting efficiency for target DNA constructs in the respective ends-in and ends-out form. For some of the constructs S. castellii showed a similar high degree of homologous recombination as S. cerevisiae. In agreement with S. cerevisiae, a higher targeting efficiency was seen for the diploid strain than for the haploid. Surprisingly, a higher degree of targeting efficiency was seen for ends-out constructs compared to ends-in constructs. This result may have been influenced by the difference in the length of the homologous target sequences used, although long homology regions of 300 bp-1 kb were used in all constructs. Remarkably, very short regions of cohesive heterologous sequences at the ends of the constructs highly stimulated random illegitimate integration, suggesting that the pathway of non-homologous end joining is highly active in S. castellii.
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| 2. |
- Berghoff, Bork A., et al.
(författare)
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RNA-based regulation in type I toxin-antitoxin systems and its implication for bacterial persistence
- 2017
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 63:6, s. 1011-1016
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Forskningsöversikt (refereegranskat)abstract
- Bacterial dormancy is a valuable survival strategy upon challenging environmental conditions. Dormant cells tolerate the consequences of high stress levels and may re-populate the environment upon return to favorable conditions. Antibiotic-tolerant bacteria-termed persisters-regularly cause relapsing infections, increase the likelihood of antibiotic resistance, and, therefore, earn increasing attention. Their generation often depends on toxins from chromosomal toxin-antitoxin systems. Here, we review recent insights concerning RNA-based control of toxin synthesis, and discuss possible implications for persister generation.
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| 3. |
- Chowdhury, Md Jamil, et al.
(författare)
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Fluorescent protein expression in the ectomycorrhizal fungus Laccaria bicolor: a plasmid toolkit for easy use of fluorescent markers in basidiomycetes
- 2020
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 66, s. 791-811
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Tidskriftsartikel (refereegranskat)abstract
- For long time, studies on ectomycorrhiza (ECM) have been limited by inefficient expression of fluorescent proteins (FPs) in the fungal partner. To convert this situation, we have evaluated the basic requirements of FP expression in the model ECM homobasidiomycete Laccaria bicolor and established eGFP and mCherry as functional FP markers. Comparison of intron-containing and intronless FP-expression cassettes confirmed that intron-processing is indispensable for efficient FP expression in Laccaria. Nuclear FP localization was obtained via in-frame fusion of FPs between the intron-containing genomic gene sequences of Laccaria histone H2B, while cytosolic FP expression was produced by incorporating the intron-containing 5 ' fragment of the glyceraldehyde-3-phosphate dehydrogenase encoding gene. In addition, we have characterized the consensus Kozak sequence of strongly expressed genes in Laccaria and demonstrated its boosting effect on transgene mRNA accumulation. Based on these results, an Agrobacterium-mediated transformation compatible plasmid set was designed for easy use of FPs in Laccaria. The four cloning plasmids presented here allow fast and highly flexible construction of C-terminal in-frame fusions between the sequences of interest and the two FPs, expressed either from the endogenous gene promoter, allowing thus evaluation of the native regulation modes of the gene under study, or alternatively, from the constitutive Agaricus bisporus gpdII promoter for enhanced cellular protein localization assays. The molecular tools described here for cell-biological studies in Laccaria can also be exploited in studies of other biotrophic or saprotrophic basidiomycete species susceptible to genetic transformation.
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| 4. |
- Cohn, Marita, et al.
(författare)
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Telomeric sequence diversity within the genus Saccharomyces
- 1998
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 33:2, s. 83-91
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Tidskriftsartikel (refereegranskat)abstract
- Conservation of telomeric DNA repeat sequences has been found across evolutionarily diverse eukaryotes. Here we report on a marked telomeric sequence diversity within the budding yeast genus Saccharomyces. Cloning and sequencing of telomeric repeat units from S. castellii, S. dairensis, S. exiguus and S. kluyveri showed a length variation between 8 and 26 bp, as well as a distinct variation in the degree of homogeneity, among the species. In S. castellii and S. dairensis, TCTGGGTG constituted a majority of the telomeric repeat units. However, the character of the variant repeats differed: in S. castellii the major class of variant repeats contained additional TG dinucleotides per repeat unit, [TCTGGGTG(TG)(1-3)], whereas in S. dairensis the major variant repeat is the shorter, uniform sequence TCTGGG. This result suggests mechanistic differences in the action of the telomerases of these closely related yeasts. Despite their length and homogeneity differences, all the Saccharomyces telomeric sequences show a conserved core which is also shared by the Candida glabrata telomeric sequence. This evolutionary similarity may be partly explained by the preservation of a binding site for the RAP1 protein.
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| 5. |
- Derouiche, Abderahmane, 1980, et al.
(författare)
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Evolution and tinkering: what do a protein kinase, a transcriptional regulator and chromosome segregation/cell division proteins have in common?
- 2016
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 62:1, s. 67-70
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Forskningsöversikt (refereegranskat)abstract
- In this study, we focus on functional interactions among multi-domain proteins which share a common evolutionary origin. The examples we develop are four Bacillus subtilis proteins, which all possess an ATP-binding Walker motif: the bacterial tyrosine kinase (BY-kinase) PtkA, the chromosome segregation protein Soj (ParA), the cell division protein MinD and a transcription regulator SalA. These proteins have arisen via duplication of the ancestral ATP-binding domain, which has undergone fusions with other functional domains in the process of divergent evolution. We point out that these four proteins, despite having very different physiological roles, engage in an unusually high number of binary functional interactions. Namely, MinD attracts Soj and PtkA to the cell pole, and in addition, activates the kinase function of PtkA. SalA also activates the kinase function of PtkA, and it gets phosphorylated by PtkA as well. The consequence of this phosphorylation is the activation of SalA as a transcriptional repressor. We hypothesize that these functional interactions remain preserved during divergent evolution and represent a constraint on the process of evolutionary "tinkering", brought about by fusions of different functional domains.
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| 6. |
- Finlay, Roger
(författare)
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Fungal stress biology: a preface to the Fungal Stress Responses special edition
- 2015
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 61, s. 231-238
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Tidskriftsartikel (refereegranskat)abstract
- There is currently an urgent need to increase global food security, reverse the trends of increasing cancer rates, protect environmental health, and mitigate climate change. Toward these ends, it is imperative to improve soil health and crop productivity, reduce food spoilage, reduce pesticide usage by increasing the use of biological control, optimize bioremediation of polluted sites, and generate energy from sustainable sources such as biofuels. This review focuses on fungi that can help provide solutions to such problems. We discuss key aspects of fungal stress biology in the context of the papers published in this Special Issue of Current Genetics. This area of biology has relevance to pure and applied research on fungal (and indeed other) systems, including biological control of insect pests, roles of saprotrophic fungi in agriculture and forestry, mycotoxin contamination of the food-supply chain, optimization of microbial fermentations including those used for bioethanol production, plant pathology, the limits of life on Earth, and astrobiology.
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| 7. |
- Finlay, Roger
(författare)
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The International Symposium on Fungal Stress: ISFUS
- 2015
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 61, s. 479-487
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Tidskriftsartikel (refereegranskat)abstract
- Fungi play central roles in many biological processes, influencing soil fertility, decomposition, cycling of minerals, and organic matter, plant health, and nutrition. They produce a wide spectrum of molecules, which are exploited in a range of industrial processes to manufacture foods, food preservatives, flavoring agents, and other useful biological products. Fungi can also be used as biological control agents of microbial pathogens, nematodes or insect pests, and affect plant growth, stress tolerance, and nutrient acquisition. Successful exploitation of fungi requires better understanding of the mechanisms that fungi use to cope with stress as well as the way in which they mediate stress tolerance in other organisms. It is against this backdrop that a scientific meeting on fungal stress was held in So Jos, dos Campos, Brazil, in October 2014. The meeting, hosted by Drauzio E. N. Rangel and Alene E. Alder-Rangel, and supported by the So Paulo Research Foundation (FAPESP), brought together more than 30 young, mid-career, and highly accomplished scientists from ten different countries. Here we summarize the highlights of the meeting.
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| 8. |
- Georgiev, Alexander, et al.
(författare)
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Characterization of MYR1, a dosage suppressor of YPT6 and RIC1 deficient mutants
- 2008
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Ingår i: Current Genetics. - Berlin : Springer. - 0172-8083 .- 1432-0983. ; 53:4, s. 235-47
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Tidskriftsartikel (refereegranskat)abstract
- Membrane traffic is tightly regulated and the Rab protein family of small GTPases plays a central role in this regulation. One member of this family is the Saccharomyces cerevisae protein Ypt6. To search for new genes interacting with Ypt6-related pathways, we performed a genetic screen for high copy suppressors of ypt6Delta temperature sensitivity at 35 degrees C. Among the suppressors, MYR1 was also able to suppress the temperature sensitive mutant lacking Ric1, a subunit of the Ypt6 guanine exchanging factor complex Ric1/Rgp1. Myr1 is characterized by a coiled coil region and a GYF domain, a protein module binding proline-rich sequences. Myr1 is able to bind membranes but is also associated with larger structures insoluble in Triton X-100. By immunofluorescence, Myr1 shows a network-like pattern as well as small foci. Overexpression of Myr1 influences nuclear envelope morphology and high levels are lethal. This lethality is rescued when the N-terminal region, containing the GYF domain, is deleted. The transcription profile of a myr1Delta strain shows effects on genes involved in nuclear migration, Ras signalling and transcription. Taken together, these results suggest that Myr1 is a novel factor linked to the secretory pathway and important cellular regulatory mechanisms.
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| 9. |
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| 10. |
- Himmelstrand, Kajsa, et al.
(författare)
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Intronic and plasmid-derived regions contribute to the large mitochondrial genome sizes of Agaricomycetes
- 2014
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 60, s. 303-313
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Tidskriftsartikel (refereegranskat)abstract
- Sizes of mitochondrial genomes vary extensively between fungal species although they typically contain a conserved set of core genes. We have characterised the mitochondrial genome of the conifer root rot pathogen Heterobasidion irregulare and compared the size, gene content and structure of 20 Basidiomycete mitochondrial genomes. The mitochondrial genome of H. irregulare was 114, 193 bp and contained a core set of 15 protein coding genes, two rRNA genes and 26 tRNA genes. In addition, we found six non-conserved open reading frames (ORFs) and four putative plasmid genes clustered in three separate regions together with 24 introns and 14 intronic homing endonuclease genes, unequally spread across seven of the core genes. The size differences among the 20 Basidiomycetes can largely be explained by length variation of intergenic regions and introns. The Agaricomycetes contained the nine largest mitochondrial genomes in the Basidiomycete group and Agaricomycete genomes are significantly (p < 0.001) larger than the other Basidiomycetes. A feature of the Agaricomycete mitochondrial genomes in this study was the simultaneous occurrence of putative plasmid genes and non-conserved ORFs, with Cantharellus cibarius as only exception, where no non-conserved ORF was identified. This indicates a mitochondrial plasmid origin of the non-conserved ORFs or increased mitochondrial genome dynamics of species harbouring mitochondrial plasmids. We hypothesise that two independent factors are the driving forces for large mitochondrial genomes: the homing endonuclease genes in introns and integration of plasmid DNA.
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| 11. |
- Hinas, Andrea, et al.
(författare)
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Treasure hunt in an amoeba : non-coding RNAs in Dictyostelium discoideum.
- 2007
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 51:3, s. 141-159
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Tidskriftsartikel (refereegranskat)abstract
- The traditional view of RNA being merely an intermediate in the transfer of genetic information, as mRNA, spliceosomal RNA, tRNA, and rRNA, has become outdated. The recent discovery of numerous regulatory RNAs with a plethora of functions in biological processes has truly revolutionized our understanding of gene regulation. Tiny RNAs such as microRNAs and small interfering RNAs play vital roles at different levels of gene control. Small nucleolar RNAs are much more abundant than previously recognized, and new functions beyond processing and modification of rRNA have recently emerged. Longer non-coding RNAs (ncRNAs) can also have important regulatory roles in the cell, e.g., antisense RNAs that control their target mRNAs. The majority of these important findings arose from analyses in various model organisms. In this review, we focus on ncRNAs in the social amoeba Dictyostelium discoideum. This important genetically tractable model organism has recently received renewed attention in terms of discovery, regulation and functional studies of ncRNAs. Old and recent findings are discussed and put in context of what we today know about ncRNAs in other organisms.
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| 12. |
- Hohmann, Stefan, 1956
(författare)
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An integrated view on a eukaryotic osmoregulation system
- 2015
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 61:3, s. 373-382
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Tidskriftsartikel (refereegranskat)abstract
- Osmoregulation encompasses active homeostatic processes that ensure proper cell volume, shape and turgor as well as an intercellular milieu optimal for the diverse biochemical processes. Recent studies demonstrate that yeast cells operate within a tight window of cellular water concentrations that still allows rapid diffusion of biomolecules while already moderate cell compression following hyper-osmotic stress leads to macromolecular crowding and a slow-down of cellular processes. Yeast cells accumulate glycerol as compatible osmolyte under hyper-osmotic stress to regain cell volume and turgor and release glycerol following a hypo-osmotic shock. The high osmolarity glycerol (HOG) response pathway controls glycerol accumulation at various levels, where each mechanism contributes to the temporal and quantitative pattern of volume recovery: inhibition of glycerol efflux, direct activation of the first enzyme in glycerol biosynthesis, stimulation of glycolytic flux as well as upregulation of expression of genes encoding enzymes in glycerol biosynthesis and an active glycerol uptake system. The HOG mitogen-activated protein kinase (MAPK) pathway communicates with the other yeast MAPK pathways to control cell morphogenesis. Cross-talk between the MAPK pathways has recently been used to re-wire osmostress-controlled expression of glycerol biosynthesis genes from Hog1 to Kss1-Fus3. The results of this study further illustrate the key importance of glycerol accumulation under osmostress and allow studying Hog1-dependent and independent processes as well as redundancy and robustness of the MAPK system.
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| 13. |
- Hughes, Diarmaid
(författare)
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Using the power of genetic suppressors to probe the essential functions of RNase E
- 2016
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 62:1, s. 53-57
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Forskningsöversikt (refereegranskat)abstract
- This review describes how, using the power of genetic suppressor analysis, mRNA turnover in bacteria was shown to be an essential function of RNase E. RNase E is an essential multifunctional enzyme in bacteria, involved in the processing of stable RNAs to their mature forms (rRNAs and tRNAs) and in the turnover of most mRNAs. Genetic suppressor analysis was successfully used to address whether mRNA turnover is one of the essential functions of RNase E. Conditional lethal mutations in rne were shown to be suppressible by three different classes of extragenic suppressors, including a class that caused overexpression of RelE. The only known function of RelE is the cleavage of mRNA in the ribosomal A-site. Suppression of the conditional lethal defect in rne by RelE overexpression provides strong genetic evidence that mRNA turnover is one of the essential functions of RNase E. Several hypotheses that could explain why mRNA turnover is essential are discussed. Suppressor analysis is an old-fashioned but very powerful approach that can be usefully applied to address a wide variety of important questions in biology and genetics. In this work suppressor analysis has revealed that mRNA turnover is an essential function of RNase E, a conclusion that raises a host of interesting questions for future research.
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| 14. |
- Hull, RM, et al.
(författare)
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The adaptive potential of circular DNA accumulation in ageing cells
- 2020
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Ingår i: Current genetics. - : Springer Science and Business Media LLC. - 1432-0983 .- 0172-8083. ; 66:5, s. 889-894
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Tidskriftsartikel (refereegranskat)abstract
- Carefully maintained and precisely inherited chromosomal DNA provides long-term genetic stability, but eukaryotic cells facing environmental challenges can benefit from the accumulation of less stable DNA species. Circular DNA molecules lacking centromeres segregate randomly or asymmetrically during cell division, following non-Mendelian inheritance patterns that result in high copy number instability and massive heterogeneity across populations. Such circular DNA species, variously known as extrachromosomal circular DNA (eccDNA), microDNA, double minutes or extrachromosomal DNA (ecDNA), are becoming recognised as a major source of the genetic variation exploited by cancer cells and pathogenic eukaryotes to acquire drug resistance. In budding yeast, circular DNA molecules derived from the ribosomal DNA (ERCs) have been long known to accumulate with age, but it is now clear that aged yeast also accumulate other high-copy protein-coding circular DNAs acquired through both random and environmentally-stimulated recombination processes. Here, we argue that accumulation of circular DNA provides a reservoir of heterogeneous genetic material that can allow rapid adaptation of aged cells to environmental insults, but avoids the negative fitness impacts on normal growth of unsolicited gene amplification in the young population.
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| 15. |
- Khananisho, Diana, et al.
(författare)
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Tips for efficiently maintaining pET expression plasmids
- 2023
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Ingår i: Current Genetics. - 0172-8083 .- 1432-0983. ; 69, s. 277-287
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Tidskriftsartikel (refereegranskat)abstract
- pET expression plasmids are widely used for producing recombinant proteins in Escherichia coli. Selection and maintenance of cells harboring a pET plasmid are possible using either a Tn3.1-type genetic fragment (which encodes a ß-lactamase and confers resistance to ß-lactam antibiotics) or a Tn903.1-type genetic fragment (which encodes an aminoglycoside-3’-phosphotransferase and confers resistance aminoglycoside antibiotics). Herein we have investigated how efficiently pET plasmids are maintained using these two fragments. The study reveals that pET plasmids are efficiently maintained with both Tn3.1 and Tn903.1 genetic fragments prior to the induction of recombinant protein production, and over short induction times (i.e., 2 h). However, over longer induction times (i.e., 20 h), the efficiency of plasmid maintenance depends on the host strain used, and the type of antibiotic selection cassette used. Based on our collective observations, we have 2 general tips for efficiently maintaining pET plasmids during recombinant production experiments.Tip #1: Use a strain with lowered levels of the T7 RNA polymerase, such as C41(DE3). pET plasmids will be efficiently maintained over long induction times with both the Tn3.1 and Tn903.1 genetic fragments, regardless of whether antibiotics are present during cultivation.Tip #2: If a strain with higher levels of T7 RNA polymerase strain is necessary, such as BL21(DE3)), keep induction times short or use a plasmid containing a Tn903.1-type fragment and select with kanamycin.
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| 16. |
- Kittl, Roman, et al.
(författare)
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Molecular cloning of three pyranose dehydrogenase-encoding genes from Agaricus meleagris and analysis of their expression by real-time RT-PCR
- 2008
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 53:2, s. 117-127
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Tidskriftsartikel (refereegranskat)abstract
- Sugar oxidoreductases such as cellobiose dehydrogenase or pyranose oxidase are widespread enzymes among fungi, whose biological function is largely speculative. We investigated a similar gene family in the mushroom Agaricus meleagris and its expression under various conditions. Three genes (named pdh1, pdh2 and pdh3) putatively encoding pyranose dehydrogenases were isolated. All three genes displayed a conserved structure and organization, and the respective cDNAs contained ORFs translating into polypeptides of 602 or 600 amino acids. The N-terminal sections of all three genes encode putative signal peptides consistent with the enzymes extracellular secretion. We cultivated the fungus on different carbon sources and analyzed the mRNA levels of all three genes over a period of several weeks using real-time RT-PCR. The glyceraldehyde-3-phosphate dehydrogenase gene from A. meleagris was also isolated and served as reference gene. pdh2 and pdh3 are essentially transcribed constitutively, whereas pdh1 expression is upregulated upon exhaustion of the carbon source; pdh1 appears to be additionally regulated under conditions of oxygen limitation. These data are consistent with an assumed role in lignocellulose degradation.
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| 17. |
- Krantz, Marcus, 1975, et al.
(författare)
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Comparative analysis of HOG pathway proteins to generate hypotheses for functional analysis
- 2006
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 49:3, s. 152-165
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Tidskriftsartikel (refereegranskat)abstract
- Comparative genomics allows comparison of different proteins that execute presumably identical functions in different organisms. In contrast to paralogues, orthologues per definition perform the same function and interact with the same partners and, consequently, should display conservation in all these properties. We have employed 20 fungal genomes to analyse key components of the high osmolarity glycerol signalling pathway of Saccharomyces cerevisiae. Among the proteins scrutinised are a complete phosphotransfer module, a MAP kinase, two scaffold proteins, one of which is also a MAPKK, and two transcription factors. Sequence alignments, domain structure and size analysis, combined with the rich information available in the literature, allowed us to probe previous structural and functional studies and to generate hypotheses for future experimental studies. Although certain domains are too highly conserved across fungal species for meaningful comparative studies, others, like interaction domains, can be studied in closely related species. Moreover, putative functionally relevant sites for protein modifications can be identified in such comparative studies. We provide several relevant examples and present a number of previously un(der)characterised domains of potential functional significance in osmosensing and signal transduction. We propose that any functional protein analysis in fungi should make use of the unique resource that fungal genome sequences offer.
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| 18. |
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| 19. |
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| 20. |
- LIDHOLM, J, et al.
(författare)
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THE CHLOROPLAST GENOME OF THE GYMNOSPERM PINUS-CONTORTA - A PHYSICAL MAP AND A COMPLETE COLLECTION OF OVERLAPPING CLONES
- 1991
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Ingår i: Current Genetics. - 0172-8083 .- 1432-0983. ; 20:1-2, s. 161-166
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Tidskriftsartikel (refereegranskat)abstract
- Overlapping restriction fragments of chloroplast DNA from the conifer Pinus contorta were cloned. Out of a total of 49 clones, 33 comprise the minimum set required to represent the entire genome. Using the purified inserts of these clones as probes in filter hybridizations, all sites for the three restriction enzymes KpnI, HpaI and SacI in the P. contorta chloroplast genome were mapped. Heterologous filter hybridizations and sequence analysis of some of the P. contorta clones were used to determine the position of 15 genes on the restriction map. The size of the genome, which lacks an inverted repeat organization, was found to be approximately 121 kilobase pairs (kbp). Unusual features of this genome are a duplication of the psbA gene and the presence of two genes, gidA and frxC, which are not found in angiosperms. The genome appeared essentially colinear with that of Pinus radiata, for which a map has previously been published. Two different restriction fragment length polymorphisms were found to be produced by variable numbers of copies of 124 bp- and 150 bp-long, tandemly repeated elements.
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| 21. |
- Linder, Tomas, et al.
(författare)
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A family of putative transcription termination factors shared amongst metazoans and plants.
- 2005
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Ingår i: Current genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 48:4, s. 265-9
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Tidskriftsartikel (refereegranskat)abstract
- The human mitochondrial transcription termination factor (mTERF) is involved in the regulation of transcription of the mitochondrial genome. Similarity searches and phylogenetic analysis demonstrate that mTERF is a member of large and complex protein family (the MTERF family) shared amongst metazoans and plants. Interestingly, we identify three novel MTERF genes in vertebrates, which all encode proteins with predicted mitochondrial localization. Members of the MTERF family have so far not been detected in fungi, supporting the notion that mitochondrial transcription regulation may have evolved separately in yeast and animal cells.
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| 22. |
- Maksimov, Vladimir, et al.
(författare)
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Stress sensitivity of a fission yeast strain lacking histidine kinases is rescued by the ectopic expression of Chk1 from Candida albicans
- 2017
-
Ingår i: Current Genetics. - : SPRINGER. - 0172-8083 .- 1432-0983. ; 63:2, s. 343-357
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Tidskriftsartikel (refereegranskat)abstract
- The development of new drugs against the pathogenic yeast Candida albicans is compelling and the evolution of relevant bioassays is important to achieve this goal. Promising drug targets are proteins that lack human counterparts which are true for the His-to-Asp phosphorelay signal transduction systems, important for stress sensing in bacteria, fungi, and plants. In the pathogenic yeast, Candida albicans, the CaChk1 histidine kinase is a trigger of the pathway that leads to a switch from yeast to hyphal growth necessary for invasion. Intriguingly, the model yeast Schizosaccharomyces pombe has a similar phosphorelay system, with three histidine kinases named Mak1, Mak2, and Mak3, which are important for the prevention of aberrant mating and sporulation on rich media. This study uncovered distinct functions for the three histidine kinases; Mak1 alone or Mak2 and Mak3 together were sufficient for the repression of the meiotic cycle when nutrients were available. Moreover, strains lacking histidine kinase genes were sensitive to various types of stress conditions in an auxotrophic strain background, while the stress sensitivity was lost in prototrophic strains. Finally, the stress sensitivity of a S. pombe strain that lacks endogenous histidine kinases could be complemented by the ectopic expression of the CaChk1 histidine kinase from C. albicans. This finding opens up for the possibility to perform a drug screen with a biological read-out in S. pombe to find inhibitors of CaChk1.
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| 23. |
- Márquez-Zacarías, Pedro, et al.
(författare)
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Why have aggregative multicellular organisms stayed simple?
- 2021
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Ingår i: Current Genetics. - : Springer. - 0172-8083 .- 1432-0983. ; 67:6, s. 871-876
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Forskningsöversikt (refereegranskat)abstract
- Multicellularity has evolved numerous times across the tree of life. One of the most fundamental distinctions among multicellular organisms is their developmental mode: whether they stay together during growth and develop clonally, or form a group through the aggregation of free-living cells. The five eukaryotic lineages to independently evolve complex multicellularity (animals, plants, red algae, brown algae, and fungi) all develop clonally. This fact has largely been explained through social evolutionary theory’s lens of cooperation and conflict, where cheating within non-clonal groups has the potential to undermine multicellular adaptation. Multicellular organisms that form groups via aggregation could mitigate the costs of cheating by evolving kin recognition systems that prevent the formation of chimeric groups. However, recent work suggests that selection for the ability to aggregate quickly may constrain the evolution of highly specific kin recognition, sowing the seeds for persistent evolutionary conflict. Importantly, other features of aggregative multicellular life cycles may independently act to constrain the evolution of complex multicellularity. All known aggregative multicellular organisms are facultatively multicellular (as opposed to obligately multicellular), allowing unicellular-level adaptation to environmental selection. Because they primarily exist in a unicellular state, it may be difficult for aggregative multicellular organisms to evolve multicellular traits that carry pleiotropic cell-level fitness costs. Thus, even in the absence of social conflict, aggregative multicellular organisms may have limited potential for the evolution of complex multicellularity.
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| 24. |
- Möller, Kerstin
(författare)
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Deafblindness: a challenge for assessment - is the ICF a useful tool?
- 2003
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Ingår i: International Journal of Audiology. - : Informa Healthcare. - 1499-2027 .- 1708-8186. ; 42, s. S140-S142
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Tidskriftsartikel (refereegranskat)abstract
- A strain of Saccharomyces cerevisiae lacking the GPD2 gene, encoding one of the glycerol-3-phosphate dehydrogenases, grows slowly under anaerobic conditions, due to reductive stress caused by the accumulation of cytoplasmic NADH. We used 2D-PAGE to study the effect on global protein expression of reductive stress in the anaerobically grown gpd2 strain. The most striking response was a strongly elevated expression of Tdh1p, the minor isoform of glyceraldehyde-3-phosphate dehydrogenase. This increased expression could be reversed by the addition of acetoin, a NADH-specific redox sink, which furthermore largely restored anaerobic growth of the gpd2 strain. Additional deletion of the TDH1 gene (but not of TDH2 or TDH3) improved anaerobic growth of the gpd2 strain. We therefore propose that TDH1 has properties not displayed by the other TDH isogenes and that its expression is regulated by reductive stress caused by an excess of cytoplasmic NADH.
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| 25. |
- Okorokova-Facanha, A L, et al.
(författare)
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An inventory of the P-type ATPases in the fission yeast Schizosaccharomyces pombe
- 2003
-
Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 43:4, s. 273-280
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Tidskriftsartikel (refereegranskat)abstract
- The analysis of the Schizosaccharomyces pombe genome revealed the presence of 14 putative P-type ATPases. The clustering of ATPases resembles that of Saccharomyces cerevisiae, indicating that the main classes of pumps were already present before the split of the Archiascomycetes from the other Ascomycota. The overall amino acid identity between fission and budding yeast P-type ATPases is generally low (30-50%). This is similar to the fungus-plant and fungus-animal comparisons.. suggesting that fungal ATPases underwent an extensive process of diversification. Unlike Sac. cerevisiae. fission yeast lacks Na+-ATPases, has a single heavy-metal ATPase and three ATPases of unknown specificity. The observed divergence within these fungi might reflect physiological differences, including adaptation to environmental stresses.
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| 26. |
- Olsson, Ida, et al.
(författare)
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Advancing our understanding of functional genome organisation through studies in the fission yeast
- 2011
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 57:1, s. 1-12
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Tidskriftsartikel (refereegranskat)abstract
- Significant progress has been made in understanding the functional organisation of the cell nucleus. Still many questions remain to be answered about the relationship between the spatial organisation of the nucleus and the regulation of the genome function. There are many conflicting data in the field making it very difficult to merge published results on mammalian cells into one model on subnuclear chromatin organisation. The fission yeast, Schizosaccharomyces pombe, over the last decades has emerged as a valuable model organism in understanding basic biological mechanisms, especially the cell cycle and chromosome biology. In this review we describe and compare the nuclear organisation in mammalian and fission yeast cells. We believe that fission yeast is a good tool to resolve at least some of the contradictions and unanswered questions concerning functional nuclear architecture, since S. pombe has chromosomes structurally similar to that of human. S. pombe also has the advantage over higher eukaryotes in that the genome can easily be manipulated via homologous recombination making it possible to integrate the tools needed for visualisation of chromosomes using live-cell microscopy. Classical genetic experiments can be used to elucidate what factors are involved in a certain mechanism. The knowledge we have gained during the last few years indicates similarities between the genome organisation in fission yeast and mammalian cells. We therefore propose the use of fission yeast for further advancement of our understanding of functional nuclear organisation.
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| 27. |
- Olsson, T G S, et al.
(författare)
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Transient inhibition of histone deacetylase activity overcomes silencing in the mating-type region in fission yeast
- 1999
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 35:2, s. 82-87
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Tidskriftsartikel (refereegranskat)abstract
- We have investigated the effects of inhibition of histone de-acetylase activity on silencing at the silent mating-type loci in fission yeast. Treatment of exponentially growing cells with the histone deacetylase inhibitor, trichostatin A (TSA), resulted in derepression of a marker gene inserted 150 bp distal from the silent mat3-M locus. The natural targets for the silencing mechanism in this region were only partially derepressed and the activation appeared to be asymmetric. i.e. the mat2-P cassette remained silent at concentrations that clearly partially derepressed the mat3-M cassette. We further noted that treatment of wild-type h(90) cells resulted in the generation of altered sporulation phenotypes, indicating that the treatment affected the expression of mating-type genes and/or mating-type switching. The results are discussed in the light of recent accumulated data regarding the role of deacetylation for silencing in other species.
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| 28. |
- Pettersson, Nina, 1974, et al.
(författare)
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Expression of heterologous aquaporins for functional analysis in Saccharomyces cerevisiae
- 2006
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 50:4, s. 247-255
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Tidskriftsartikel (refereegranskat)abstract
- In this study the yeast Saccharomyces cerevisiae, which is a genetically tractable model for analysis of osmoregulation, has been used for analysis of heterologous aquaporins. Aquaporin water channels play important roles in the control of water homeostasis in individual cells and multicellular organisms. We have investigated the effects of functional expression of the mammalian aquaporins AQP1 and AQP5 and the aquaglyceroporins AQP3 and AQP9. Expression of aquaporins caused moderate growth inhibition under hyperosmotic stress, while expression of aquaglyceroporins mediated strong growth inhibition due to glycerol loss. Water transport was monitored in protoplasts, where the kinetics of bursting was influenced by presence of aquaporins but not aquaglyceroporins. We observed glycerol transport through aquaglyceroporins, but not aquaporins, in a yeast strain deficient in glycerol production, whose growth depends on glycerol inflow. In addition, a gene reporter assay allowed to indirectly monitor the effect of AQP9-mediated enhanced glycerol loss on osmoadaptation. Transport activity of certain aqua(glycero)porins was diminished by low pH or CuSO4, suggesting that yeast can potentially be used for screening of putative aquaporin inhibitors. We conclude that yeast is a versatile system for functional studies of aquaporins, and it can be developed to screen for compounds of potential pharmacological use
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| 29. |
- Sabouri, Nasim
(författare)
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The functions of the multi‑tasking Pfh1Pif1 helicase
- 2017
-
Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 63:4, s. 621-626
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Forskningsöversikt (refereegranskat)abstract
- Approximately, 1% of the genes in eukaryotic genomes encode for helicases, which make the number of helicases expressed in the cell considerably high. Helicases are motor proteins that participate in many central aspects of the nuclear and mitochondrial genomes, and based on their helicase motif conservation, they are divided into different helicase families. The Pif1 family of helicases is an evolutionarily conserved helicase family that is associated with familial breast cancer in humans. The Schizosaccharomyces pombe Pfh1 helicase belongs to the Pif1 helicase family and is a multi-tasking helicase that is important for replication fork progression through natural fork barriers, for G-quadruplex unwinding, and for Okazaki fragment maturation, and these activities are potentially shared by the human Pif1 helicase. This review discusses the known functions of the Pfh1 helicase, the study of which has led to a better understanding of nucleic acid metabolism in eukaryotes.
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| 30. |
- Schothorst, Joep, et al.
(författare)
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Yeast nutrient transceptors provide novel insight in the functionality of membrane transporters.
- 2013
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Ingår i: Current Genetics. - : Springer. - 0172-8083 .- 1432-0983. ; 59:4, s. 197-206
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Tidskriftsartikel (refereegranskat)abstract
- In the yeast Saccharomyces cerevisiae several nutrient transporters have been identified that possess an additional function as nutrient receptor. These transporters are induced when yeast cells are starved for their substrate, which triggers entry into stationary phase and acquirement of a low protein kinase A (PKA) phenotype. Re-addition of the lacking nutrient triggers exit from stationary phase and sudden activation of the PKA pathway, the latter being mediated by the nutrient transceptors. At the same time, the transceptors are ubiquitinated, endocytosed and sorted to the vacuole for breakdown. Investigation of the signaling function of the transceptors has provided a new read-out and new tools for gaining insight into the functionality of transporters. Identification of amino acid residues that bind co-transported ions in symporters has been challenging because the inactivation of transport by site-directed mutagenesis is not conclusive with respect to the cause of the inactivation. The discovery of nontransported agonists of the signaling function in transceptors has shown that transport is not required for signaling. Inactivation of transport with maintenance of signaling in transceptors supports that a true proton-binding residue was mutagenised. Determining the relationship between transport and induction of endocytosis has also been challenging, since inactivation of transport by mutagenesis easily causes loss of all affinity for the substrate. The use of analogues with different combinations of transport and signaling capacities has revealed that transport, ubiquitination and endocytosis can be uncoupled in several unexpected ways. The results obtained are consistent with transporters undergoing multiple substrate-induced conformational changes, which allow interaction with different accessory proteins to trigger specific downstream events.
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| 31. |
- Silverstein, Rebecca A, et al.
(författare)
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Sin3 : a flexible regulator of global gene expression and genome stability
- 2005
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 47:1, s. 1-17
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Tidskriftsartikel (refereegranskat)abstract
- SIN3 was first identified genetically as a global regulator of transcription. Sin3 is a large protein composed mainly of protein-interaction domains, whose function is to provide structural support for a heterogeneous Sin3/histone deacetylase (HDAC) complex. The core Sin3/HDAC complex is conserved from yeast to man and consists of eight proteins. In addition to HDACs, Sin3 can sequester other enzymatic functions, including nucleosome remodeling, DNA methylation, N-acetylglucoseamine transferase activity, and histone methylation. Since the Sin3/HDAC complex lacks any DNA-binding activity, it must be targeted to gene promoters by interacting with DNA-binding proteins. Although most research on Sin3 has focused on its role as a corepressor, mounting evidence suggests that Sin3 can also positively regulate transcription. Furthermore, Sin3 is key to the propagation of epigenetically silenced domains and is required for centromere function. Thus, Sin3 provides a platform to deliver multiple combinations modifications to the chromatin, using both sequence-specific and sequence-independent mechanisms.
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| 32. |
- Simoff, Ivailo, 1971-, et al.
(författare)
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Functional characterization of ribosomal protein L15 from Saccaromyces cerevisiae
- 2009
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 55:2, s. 111-125
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Tidskriftsartikel (refereegranskat)abstract
- In this study we provide general information on the little studied eukaryotic ribosomal protein rpL15. Saccharomyces cerevisiae has two genes, YRPL15A and YRPL15B that could potentially code for yeast rpL15 (YrpL15). YRPL15A is essential while YRPL15B is dispensable. However, a plasmid-borne copy of the YRPL15B gene, controlled by the GAL1 promoter or by the promoter controlling expression of the YRPL15A gene, can functionally complement YrpL15A in yeast cells, while the same gene controlled by the authentic promoter is inactive. Analysis of the levels of YrpL15B-mRNA in yeast cells shows that the YRPL15B gene is inactive in transcription. The function of YrpL15A is highly resilient to single and multiple amino acid substitutions. In addition, minor deletions from both the N- and C-terminal ends of YrpL15A has no effect on protein function, while addition of a C-terminal tag that could be used for detection of plasmid-encoded YrpL15A is detrimental to protein function. YrpL15A could also be replaced by the homologous protein from Arabidopsis thaliana despite almost 30% differences in the amino acid sequence, while the more closely related protein from Schizosaccharomyces pombe was inactive. The lack of function was not caused by a failure of the protein to enter the yeast nucleus.
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| 33. |
- Soederstroem, Bill, et al.
(författare)
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The bacterial divisome : more than a ring?
- 2017
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 63:2, s. 161-164
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Forskningsöversikt (refereegranskat)abstract
- Bacterial cells are critically dependent on their ability to divide. The process of division is carried out by a large and highly dynamic molecular machine, known as the divisome. An understanding of the divisomes' architecture is highly sought after, as it is essential for understanding molecular mechanisms and potentially designing antibiotic molecules that curb bacterial growth. Our current view, which is mainly based on high-resolution imaging of Escherichia coli, is that it is a patchy ring or toroid structure. However, recent super-resolution imaging has shown that the toroid structure contains at least three concentric rings, each containing a different set of proteins. Thus, the emerging picture is that the divisome has different functional modules that are spatially separated in concentric rings.
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| 34. |
- Söderström, Bill, et al.
(författare)
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Super-resolution images of peptidoglycan remodelling enzymes at the division site of Escherichia coli
- 2019
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 65:1, s. 99-101
-
Forskningsöversikt (refereegranskat)abstract
- Bacterial cells need to divide. This process requires more than 30 different proteins, which gather at the division site. It is widely assumed that these proteins assemble into a macromolecular complex (the divisome), but capturing the molecular layout of this complex has proven elusive. Super-resolution microscopy can provide spatial information, down to a few tens of nanometers, about how the division proteins assemble into complexes and how their activities are co-ordinated. Herein we provide insight into recent work from our laboratories, where we used super-resolution gSTED nanoscopy to explore the molecular organization of FtsZ, FtsI and FtsN. The resulting images show that all three proteins form discrete densities organised in patchy pseudo-rings at the division site. Significantly, two-colour imaging highlighted a radial separation between FtsZ and FtsN, indicating that there is more than one type of macromolecular complex operating during division. These data provide a first glimpse into the spatial organisation of PG-synthesising enzymes during division in Gram-negative bacteria.
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| 35. |
- Tamás, Markus J., 1970, et al.
(författare)
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Misfolding and aggregation of nascent proteins: a novel mode of toxic cadmium action in vivo.
- 2018
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Ingår i: Current genetics. - : Springer Science and Business Media LLC. - 1432-0983 .- 0172-8083. ; 64:1, s. 177-181
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Forskningsöversikt (refereegranskat)abstract
- Cadmium is a highly poisonous metal and a human carcinogen, but the molecular mechanisms underlying its cellular toxicity are not fully understood. Recent findings in yeast cells indicate that cadmium exerts its deleterious effects by inducing widespread misfolding and aggregation of nascent proteins. Here, we discuss this novel mode of toxic heavy metal action and propose a mechanism by which molecular chaperones may reduce the damaging effects of heavy metal ions on protein structures.
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| 36. |
- Valadi, Hadi, 1963, et al.
(författare)
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NADH-reductive stress in Saccharomyces cerevisiae induces the expression of the minor isoform of glyceraldehyde-3-phosphate dehydrogenase (TDH1)
- 2004
-
Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 45:2, s. 90-95
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Tidskriftsartikel (refereegranskat)abstract
- A strain of Saccharomyces cerevisiae lacking the GPD2 gene, encoding one of the glycerol-3-phosphate dehydrogenases, grows slowly under anaerobic conditions, due to reductive stress caused by the accumulation of cytoplasmic NADH. We used 2D-PAGE to study the effect on global protein expression of reductive stress in the anaerobically grown gpd2Delta strain. The most striking response was a strongly elevated expression of Tdh1p, the minor isoform of glyceraldehyde-3-phosphate dehydrogenase. This increased expression could be reversed by the addition of acetoin, a NADH-specific redox sink, which furthermore largely restored anaerobic growth of the gpd2Delta strain. Additional deletion of the TDH1 gene (but not of TDH2 or TDH3) improved anaerobic growth of the gpd2Delta strain. We therefore propose that TDH1 has properties not displayed by the other TDH isogenes and that its expression is regulated by reductive stress caused by an excess of cytoplasmic NADH.
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| 37. |
- Veide Vilg, Jenny, 1973, et al.
(författare)
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Application of a peptide-based assay to characterize inhibitors targeting protein kinases from yeast
- 2014
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 60:3, s. 193-200
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Tidskriftsartikel (refereegranskat)abstract
- Chemical molecules that inhibit protein kinase activity are important tools to assess the functions of protein kinases in living cells. To develop, test and characterize novel inhibitors, a convenient and reproducible kinase assay is of importance. Here, we applied a biotinylated peptide-based method to assess adenosine triphosphate-competitive inhibitors that target the yeast kinases Hog1, Elm1 and Elm1-as. The peptide substrates contained 13 amino acids, encompassing the consensus sequence surrounding the phosphorylation site. To test whether the lack of distal sites affects inhibitor efficacy, we compared the peptide-based assay with an assay using full-length protein as substrate. Similar inhibitor efficiencies were obtained irrespective of whether peptide or full-length protein was used as kinase substrates. Thus, we demonstrate that the peptide substrates used previously (Dinér et al. in PLoS One 6(5):e20012, 2011) give accurate results compared with protein substrates. We also show that the peptide-based method is suitable for selectivity assays and for inhibitor screening. The use of biotinylated peptide substrates provides a simple and reliable assay for protein kinase inhibitor characterization. The utility of this approach is discussed. © 2014 Springer-Verlag Berlin Heidelberg.
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| 38. |
- Westlund, Emma, et al.
(författare)
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Application of nanotags and nanobodies for live cell single-molecule imaging of the Z-ring in Escherichia coli
- 2023
-
Ingår i: Current Genetics. - 0172-8083 .- 1432-0983. ; 69:2-3, s. 153-163
-
Tidskriftsartikel (refereegranskat)abstract
- Understanding where proteins are localized in a bacterial cell is essential for understanding their function and regulation. This is particularly important for proteins that are involved in cell division, which localize at the division septum and assemble into highly regulated complexes. Current knowledge of these complexes has been greatly facilitated by super-resolution imaging using fluorescent protein fusions. Herein, we demonstrate with FtsZ that single-molecule PALM images can be obtained in-vivo using a genetically fused nanotag (ALFA), and a corresponding nanobody fused to mEos3.2. The methodology presented is applicable to other bacterial proteins.
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| 39. |
- Xu, Fu, et al.
(författare)
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SSD1 modifies phenotypes of Elongator mutants
- 2020
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Ingår i: Current Genetics. - : Springer-Verlag New York. - 0172-8083 .- 1432-0983. ; 66, s. 481-485
-
Forskningsöversikt (refereegranskat)abstract
- The translational decoding properties of tRNAs are influenced by post-transcriptional modification of nucleosides in their anticodon region. The Elongator complex promotes the first step in the formation of 5-methoxycarbonylmethyl (mcm(5)), 5-methoxycarbonylhydroxymethyl (mchm(5)), and 5-carbamoylmethyl (ncm(5)) groups on wobble uridine residues in eukaryotic cytosolic tRNAs. Elongator mutants in yeast, worms, plants, mice, and humans not only show a tRNA modification defect, but also a diverse range of additional phenotypes. Even though the phenotypes are almost certainly caused by the reduced functionality of the hypomodified tRNAs in translation, the basis for specific phenotypes is not well understood. Here, we discuss the recent finding that the phenotypes of Saccharomyces cerevisiae Elongator mutants are modulated by the genetic background. This background-effect is largely due to the allelic variation at the SSD1 locus, which encodes an mRNA-binding protein involved in post-transcriptional regulation of gene expression. A nonsense ssd1 allele is found in several wild-type laboratory strains and the presence of this allele aggravates the stress-induced phenotypes of Elongator mutants. Moreover, other phenotypes, such as the histone acetylation and telomeric gene silencing defects, are dependent on the mutant ssd1 allele. Thus, SSD1 is a genetic modifier of the phenotypes of Elongator-deficient yeast cells.
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| 40. |
- Yuen, Jonathan
(författare)
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Mitochondrial DNA assessment of Phytophthora infestans isolates from potato and tomato in Ethiopia reveals unexpected diversity
- 2016
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Ingår i: Current Genetics. - : Springer Science and Business Media LLC. - 0172-8083 .- 1432-0983. ; 62, s. 657-667
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Tidskriftsartikel (refereegranskat)abstract
- Mitochondrial DNA (mtDNA) haplotypes were determined using restriction fragment length polymorphism (RFLP) for P. infestans sampled from 513 foliar lesions of late blight found on potato and tomato in different regions of Ethiopia. Among the four reported mitochondrial haplotypes of Phytophthora infestans, Ia, Ib and IIb were detected in 93 % of the samples analyzed but the vast majority of these were Ia. The remaining 7 % represented a previously unreported haplotype. DNA sequencing of this new haplotype also confirmed a single base nucleotide substitution that resulted in loss of EcoRI restriction site and gain of two additional MspI sites in cox1 and atp1 genes, respectively. There were 28 polymorphic sites among all nucleotide sequences including five reference isolates. Sites with alignment gaps were observed in P4 with one nucleotide deletion in 11 Ethiopian isolates. None of the reference sequence produced frame-shifts, with the exception of the 3-nucleotide deletion in the P4 region by Phytophthora andina, a feature that can be used to distinguish the new Ethiopian isolates from P. andina. While a distinguishing molecular data presented here clearly separated them from P. infestans, 7 % of the isolates that share this feature formed an important component of the late blight pathogen causing disease on Solanum tuberosum in Ethiopia. Thus, these Ethiopian isolates could represent a novel Phytophthora species reported for the first time here.
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| 41. |
- Grube, M, et al.
(författare)
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An exceptional group-I intron-like insertion in the SSU rDNA of lichen mycobionts
- 1999
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Ingår i: CURRENT GENETICS. - : SPRINGER VERLAG. - 0172-8083. ; 35:5, s. 536-541
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- An exceptional group-I intron-like insertion at position 940 of the nuclear small subunit rDNA is found in lichen mycobionts of the families Parmeliaceae and Lecanoraceae. This shared insertion site is exceptional as it follows a G. Although several featu
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