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Yadav V, Sun S, Heitman J. On the evolution of variation in sexual reproduction through the prism of eukaryotic microbes. Proc Natl Acad Sci U S A 2023; 120:e2219120120. [PMID: 36867686 PMCID: PMC10013875 DOI: 10.1073/pnas.2219120120] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 01/23/2023] [Indexed: 03/05/2023] Open
Abstract
Almost all eukaryotes undergo sexual reproduction to generate diversity and select for fitness in their population pools. Interestingly, the systems by which sex is defined are highly diverse and can even differ between evolutionarily closely related species. While the most commonly known form of sex determination involves males and females in animals, eukaryotic microbes can have as many as thousands of different mating types for the same species. Furthermore, some species have found alternatives to sexual reproduction and prefer to grow clonally and yet undergo infrequent facultative sexual reproduction. These organisms are mainly invertebrates and microbes, but several examples are also present among vertebrates suggesting that alternative modes of sexual reproduction evolved multiple times throughout evolution. In this review, we summarize the sex-determination modes and variants of sexual reproduction found across the eukaryotic tree of life and suggest that eukaryotic microbes provide unique opportunities to study these processes in detail. We propose that understanding variations in modes of sexual reproduction can serve as a foundation to study the evolution of sex and why and how it evolved in the first place.
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Affiliation(s)
- Vikas Yadav
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC27710
| | - Sheng Sun
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC27710
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC27710
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2
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Mating-Type Switching in Budding Yeasts, from Flip/Flop Inversion to Cassette Mechanisms. Microbiol Mol Biol Rev 2022; 86:e0000721. [PMID: 35195440 PMCID: PMC8941940 DOI: 10.1128/mmbr.00007-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mating-type switching is a natural but unusual genetic control process that regulates cell identity in ascomycete yeasts. It involves physically replacing one small piece of genomic DNA by another, resulting in replacement of the master regulatory genes in the mating pathway and hence a switch of cell type and mating behavior. In this review, we concentrate on recent progress that has been made on understanding the origins and evolution of mating-type switching systems in budding yeasts (subphylum Saccharomycotina). Because of the unusual nature and the complexity of the mechanism in Saccharomyces cerevisiae, mating-type switching was assumed until recently to have originated only once or twice during yeast evolution. However, comparative genomics analysis now shows that switching mechanisms arose many times independently-at least 11 times in budding yeasts and once in fission yeasts-a dramatic example of convergent evolution. Most of these lineages switch mating types by a flip/flop mechanism that inverts a section of a chromosome and is simpler than the well-characterized 3-locus cassette mechanism (MAT/HML/HMR) used by S. cerevisiae. Mating-type switching (secondary homothallism) is one of the two possible mechanisms by which a yeast species can become self-fertile. The other mechanism (primary homothallism) has also emerged independently in multiple evolutionary lineages of budding yeasts, indicating that homothallism has been favored strongly by natural selection. Recent work shows that HO endonuclease, which makes the double-strand DNA break that initiates switching at the S. cerevisiae MAT locus, evolved from an unusual mobile genetic element that originally targeted a glycolytic gene, FBA1.
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3
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Chang J, Bei J, Shao Q, Wang H, Fan H, Yau TO, Bu W, Ruan J, Wei D, Gao S. Full-Length Genome of an Ogataea polymorpha Strain CBS4732 ura3Δ Reveals Large Duplicated Segments in Subtelomeric Regions. Front Microbiol 2022; 13:855666. [PMID: 35464988 PMCID: PMC9019687 DOI: 10.3389/fmicb.2022.855666] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 02/25/2022] [Indexed: 11/18/2022] Open
Abstract
Background Currently, methylotrophic yeasts (e.g., Pichia pastoris, Ogataea polymorpha, and Candida boindii) are subjects of intense genomics studies in basic research and industrial applications. In the genus Ogataea, most research is focused on three basic O. polymorpha strains-CBS4732, NCYC495, and DL-1. However, the relationship between CBS4732, NCYC495, and DL-1 remains unclear, as the genomic differences between them have not be exactly determined without their high-quality complete genomes. As a nutritionally deficient mutant derived from CBS4732, the O. polymorpha strain CBS4732 ura3Δ (named HU-11) is being used for high-yield production of several important proteins or peptides. HU-11 has the same reference genome as CBS4732 (noted as HU-11/CBS4732), because the only genomic difference between them is a 5-bp insertion. Results In the present study, we have assembled the full-length genome of O. polymorpha HU-11/CBS4732 using high-depth PacBio and Illumina data. Long terminal repeat retrotransposons (LTR-rts), rDNA, 5′ and 3′ telomeric, subtelomeric, low complexity and other repeat regions were exactly determined to improve the genome quality. In brief, the main findings include complete rDNAs, complete LTR-rts, three large duplicated segments in subtelomeric regions and three structural variations between the HU-11/CBS4732 and NCYC495 genomes. These findings are very important for the assembly of full-length genomes of yeast and the correction of assembly errors in the published genomes of Ogataea spp. HU-11/CBS4732 is so phylogenetically close to NCYC495 that the syntenic regions cover nearly 100% of their genomes. Moreover, HU-11/CBS4732 and NCYC495 share a nucleotide identity of 99.5% through their whole genomes. CBS4732 and NCYC495 can be regarded as the same strain in basic research and industrial applications. Conclusion The present study preliminarily revealed the relationship between CBS4732, NCYC495, and DL-1. Our findings provide new opportunities for in-depth understanding of genome evolution in methylotrophic yeasts and lay the foundations for the industrial applications of O. polymorpha CBS4732, NCYC495, DL-1, and their derivative strains. The full-length genome of O. polymorpha HU-11/CBS4732 should be included into the NCBI RefSeq database for future studies of Ogataea spp.
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Affiliation(s)
- Jia Chang
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Science, Nankai University, Tianjin, China
| | - Jinlong Bei
- Agro-Biological Gene Research Center, Guangdong Academy of Agricultural Sciences, Guangdong Provincial Key Laboratory for Crop Germplasm Resources Preservation and Utilization, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Qi Shao
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Science, Nankai University, Tianjin, China
| | - Hemu Wang
- Tianjin Hemu Health Biotechnological Co., Ltd., Tianjin, China
| | - Huan Fan
- Tianjin Institute of Animal Husbandry and Veterinary Research, Tianjin, China
| | - Tung On Yau
- John Van Geest Cancer Research Centre, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom.,Department of Rural Land Use, Scotland's Rural College, Aberdeen, United Kingdom
| | - Wenjun Bu
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Science, Nankai University, Tianjin, China
| | - Jishou Ruan
- School of Mathematical Sciences, Nankai University, Tianjin, China
| | - Dongsheng Wei
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Science, Nankai University, Tianjin, China
| | - Shan Gao
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Science, Nankai University, Tianjin, China
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4
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Ata Ö, Ergün BG, Fickers P, Heistinger L, Mattanovich D, Rebnegger C, Gasser B. What makes Komagataella phaffii non-conventional? FEMS Yeast Res 2021; 21:6440159. [PMID: 34849756 PMCID: PMC8709784 DOI: 10.1093/femsyr/foab059] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 11/23/2021] [Indexed: 12/30/2022] Open
Abstract
The important industrial protein production host Komagataella phaffii (syn Pichia pastoris) is classified as a non-conventional yeast. But what exactly makes K. phaffii non-conventional? In this review, we set out to address the main differences to the 'conventional' yeast Saccharomyces cerevisiae, but also pinpoint differences to other non-conventional yeasts used in biotechnology. Apart from its methylotrophic lifestyle, K. phaffii is a Crabtree-negative yeast species. But even within the methylotrophs, K. phaffii possesses distinct regulatory features such as glycerol-repression of the methanol-utilization pathway or the lack of nitrate assimilation. Rewiring of the transcriptional networks regulating carbon (and nitrogen) source utilization clearly contributes to our understanding of genetic events occurring during evolution of yeast species. The mechanisms of mating-type switching and the triggers of morphogenic phenotypes represent further examples for how K. phaffii is distinguished from the model yeast S. cerevisiae. With respect to heterologous protein production, K. phaffii features high secretory capacity but secretes only low amounts of endogenous proteins. Different to S. cerevisiae, the Golgi apparatus of K. phaffii is stacked like in mammals. While it is tempting to speculate that Golgi architecture is correlated to the high secretion levels or the different N-glycan structures observed in K. phaffii, there is recent evidence against this. We conclude that K. phaffii is a yeast with unique features that has a lot of potential to explore both fundamental research questions and industrial applications.
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Affiliation(s)
- Özge Ata
- Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, University of Natural Resources and Life Sciences Vienna (BOKU), Muthgasse 18, 1190 Vienna, Austria.,Austrian Centre of Industrial Biotechnology (ACIB), Muthgasse 11, 1190 Vienna, Austria
| | - Burcu Gündüz Ergün
- UNAM-National Nanotechnology Research Center, Bilkent University, Ankara, Turkey.,Biotechnology Research Center, Ministry of Agriculture and Forestry, Ankara, Turkey
| | - Patrick Fickers
- Microbial Processes and Interactions, TERRA Teaching and Research Centre, Gembloux Agro-Bio Tech, University of Liège, Av. de la Faculté 2B, 5030 Gembloux, Belgium
| | - Lina Heistinger
- Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, University of Natural Resources and Life Sciences Vienna (BOKU), Muthgasse 18, 1190 Vienna, Austria.,Austrian Centre of Industrial Biotechnology (ACIB), Muthgasse 11, 1190 Vienna, Austria.,Christian Doppler Laboratory for Innovative Immunotherapeutics, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, 1190 Vienna, Austria
| | - Diethard Mattanovich
- Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, University of Natural Resources and Life Sciences Vienna (BOKU), Muthgasse 18, 1190 Vienna, Austria.,Austrian Centre of Industrial Biotechnology (ACIB), Muthgasse 11, 1190 Vienna, Austria
| | - Corinna Rebnegger
- Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, University of Natural Resources and Life Sciences Vienna (BOKU), Muthgasse 18, 1190 Vienna, Austria.,Austrian Centre of Industrial Biotechnology (ACIB), Muthgasse 11, 1190 Vienna, Austria.,Christian Doppler Laboratory for Growth-Decoupled Protein Production in Yeast, University of Natural Resources and Life Sciences Vienna (BOKU), Muthgasse 18, 1190 Vienna, Austria
| | - Brigitte Gasser
- Department of Biotechnology, Institute of Microbiology and Microbial Biotechnology, University of Natural Resources and Life Sciences Vienna (BOKU), Muthgasse 18, 1190 Vienna, Austria.,Austrian Centre of Industrial Biotechnology (ACIB), Muthgasse 11, 1190 Vienna, Austria.,Biotechnology Research Center, Ministry of Agriculture and Forestry, Ankara, Turkey
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5
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Solieri L, Cassanelli S, Huff F, Barroso L, Branduardi P, Louis EJ, Morrissey JP. Insights on life cycle and cell identity regulatory circuits for unlocking genetic improvement in Zygosaccharomyces and Kluyveromyces yeasts. FEMS Yeast Res 2021; 21:foab058. [PMID: 34791177 PMCID: PMC8673824 DOI: 10.1093/femsyr/foab058] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 11/14/2021] [Indexed: 11/14/2022] Open
Abstract
Evolution has provided a vast diversity of yeasts that play fundamental roles in nature and society. This diversity is not limited to genotypically homogeneous species with natural interspecies hybrids and allodiploids that blur species boundaries frequently isolated. Thus, life cycle and the nature of breeding systems have profound effects on genome variation, shaping heterozygosity, genotype diversity and ploidy level. The apparent enrichment of hybrids in industry-related environments suggests that hybridization provides an adaptive route against stressors and creates interest in developing new hybrids for biotechnological uses. For example, in the Saccharomyces genus where regulatory circuits controlling cell identity, mating competence and meiosis commitment have been extensively studied, this body of knowledge is being used to combine interesting traits into synthetic F1 hybrids, to bypass F1 hybrid sterility and to dissect complex phenotypes by bulk segregant analysis. Although these aspects are less known in other industrially promising yeasts, advances in whole-genome sequencing and analysis are changing this and new insights are being gained, especially in the food-associated genera Zygosaccharomyces and Kluyveromyces. We discuss this new knowledge and highlight how deciphering cell identity circuits in these lineages will contribute significantly to identify the genetic determinants underpinning complex phenotypes and open new avenues for breeding programmes.
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Affiliation(s)
- Lisa Solieri
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Amendola 2, 42122 Reggio Emilia, Italy
| | - Stefano Cassanelli
- Department of Life Sciences, University of Modena and Reggio Emilia, Via Amendola 2, 42122 Reggio Emilia, Italy
| | - Franziska Huff
- School of Microbiology, APC Microbiome Ireland, Environmental Research Institute, University College Cork, Cork T12 K8AF, Ireland
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, UK
| | - Liliane Barroso
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, UK
- Department of Biotechnology and Biosciences, University of Milano Bicocca, Piazza della Scienza, 2-20126 Milano, Italy
| | - Paola Branduardi
- Department of Biotechnology and Biosciences, University of Milano Bicocca, Piazza della Scienza, 2-20126 Milano, Italy
| | - Edward J Louis
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, UK
| | - John P Morrissey
- School of Microbiology, APC Microbiome Ireland, Environmental Research Institute, University College Cork, Cork T12 K8AF, Ireland
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6
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Genome sequencing of the neotype strain CBS 554.65 reveals the MAT1-2 locus of Aspergillus niger. BMC Genomics 2021; 22:679. [PMID: 34548025 PMCID: PMC8454179 DOI: 10.1186/s12864-021-07990-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 09/03/2021] [Indexed: 12/05/2022] Open
Abstract
Background Aspergillus niger is a ubiquitous filamentous fungus widely employed as a cell factory thanks to its abilities to produce a wide range of organic acids and enzymes. Its genome was one of the first Aspergillus genomes to be sequenced in 2007, due to its economic importance and its role as model organism to study fungal fermentation. Nowadays, the genome sequences of more than 20 A. niger strains are available. These, however, do not include the neotype strain CBS 554.65. Results The genome of CBS 554.65 was sequenced with PacBio. A high-quality nuclear genome sequence consisting of 17 contigs with a N50 value of 4.07 Mbp was obtained. The assembly covered all the 8 centromeric regions of the chromosomes. In addition, a complete circular mitochondrial DNA assembly was obtained. Bioinformatic analyses revealed the presence of a MAT1-2-1 gene in this genome, contrary to the most commonly used A. niger strains, such as ATCC 1015 and CBS 513.88, which contain a MAT1-1-1 gene. A nucleotide alignment showed a different orientation of the MAT1–1 locus of ATCC 1015 compared to the MAT1–2 locus of CBS 554.65, relative to conserved genes flanking the MAT locus. Within 24 newly sequenced isolates of A. niger half of them had a MAT1–1 locus and the other half a MAT1–2 locus. The genomic organization of the MAT1–2 locus in CBS 554.65 is similar to other Aspergillus species. In contrast, the region comprising the MAT1–1 locus is flipped in all sequenced strains of A. niger. Conclusions This study, besides providing a high-quality genome sequence of an important A. niger strain, suggests the occurrence of genetic flipping or switching events at the MAT1–1 locus of A. niger. These results provide new insights in the mating system of A. niger and could contribute to the investigation and potential discovery of sexuality in this species long thought to be asexual. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-07990-8.
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7
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Hanson SJ, Cinnéide EÓ, Salzberg LI, Wolfe KH, McGowan J, Fitzpatrick DA, Matlin K. Genomic diversity, chromosomal rearrangements, and interspecies hybridization in the Ogataea polymorpha species complex. G3 (BETHESDA, MD.) 2021; 11:jkab211. [PMID: 34849824 PMCID: PMC8496258 DOI: 10.1093/g3journal/jkab211] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 06/11/2021] [Indexed: 11/13/2022]
Abstract
The methylotrophic yeast Ogataea polymorpha has long been a useful system for recombinant protein production, as well as a model system for methanol metabolism, peroxisome biogenesis, thermotolerance, and nitrate assimilation. It has more recently become an important model for the evolution of mating-type switching. Here, we present a population genomics analysis of 47 isolates within the O. polymorpha species complex, including representatives of the species O. polymorpha, Ogataea parapolymorpha, Ogataea haglerorum, and Ogataea angusta. We found low levels of nucleotide sequence diversity within the O. polymorpha species complex and identified chromosomal rearrangements both within and between species. In addition, we found that one isolate is an interspecies hybrid between O. polymorpha and O. parapolymorpha and present evidence for loss of heterozygosity following hybridization.
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Affiliation(s)
- Sara J Hanson
- Department of Molecular Biology, Colorado College, Colorado Springs, CO 80903, USA
| | - Eoin Ó Cinnéide
- School of Medicine, UCD Conway Institute, University College Dublin, Dublin 4, Ireland
| | - Letal I Salzberg
- School of Medicine, UCD Conway Institute, University College Dublin, Dublin 4, Ireland
| | - Kenneth H Wolfe
- School of Medicine, UCD Conway Institute, University College Dublin, Dublin 4, Ireland
| | - Jamie McGowan
- Genome Evolution Laboratory, Department of Biology, Maynooth University, Maynooth, Ireland
- Kathleen Lonsdale Institute for Human Health Research, Maynooth University, Maynooth, Ireland
| | - David A Fitzpatrick
- Genome Evolution Laboratory, Department of Biology, Maynooth University, Maynooth, Ireland
- Kathleen Lonsdale Institute for Human Health Research, Maynooth University, Maynooth, Ireland
| | - Kate Matlin
- Department of Molecular Biology, Colorado College, Colorado Springs, CO 80903, USA
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8
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A conserved regulator controls asexual sporulation in the fungal pathogen Candida albicans. Nat Commun 2020; 11:6224. [PMID: 33277479 PMCID: PMC7718266 DOI: 10.1038/s41467-020-20010-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 11/03/2020] [Indexed: 12/16/2022] Open
Abstract
Transcription factor Rme1 is conserved among ascomycetes and regulates meiosis and pseudohyphal growth in Saccharomyces cerevisiae. The genome of the meiosis-defective pathogen Candida albicans encodes an Rme1 homolog that is part of a transcriptional circuitry controlling hyphal growth. Here, we use chromatin immunoprecipitation and genome-wide expression analyses to study a possible role of Rme1 in C. albicans morphogenesis. We find that Rme1 binds upstream and activates the expression of genes that are upregulated during chlamydosporulation, an asexual process leading to formation of large, spherical, thick-walled cells during nutrient starvation. RME1 deletion abolishes chlamydosporulation in three Candida species, whereas its overexpression bypasses the requirement for chlamydosporulation cues and regulators. RME1 expression levels correlate with chlamydosporulation efficiency across clinical isolates. Interestingly, RME1 displays a biphasic pattern of expression, with a first phase independent of Rme1 function and dependent on chlamydospore-inducing cues, and a second phase dependent on Rme1 function and independent of chlamydospore-inducing cues. Our results indicate that Rme1 plays a central role in chlamydospore development in Candida species.
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9
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Carbon source requirements for mating and mating‐type switching in the methylotrophic yeasts
Ogataea (Hansenula) polymorpha
and
Komagataella phaffii (Pichia pastoris). Yeast 2020; 37:237-245. [DOI: 10.1002/yea.3446] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 10/08/2019] [Accepted: 10/12/2019] [Indexed: 12/20/2022] Open
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10
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Mating-type switching and mating-type gene array expression in the methylotrophic yeast Ogataea thermomethanolica TBRC656. Microbiol Res 2019; 232:126372. [PMID: 31759230 DOI: 10.1016/j.micres.2019.126372] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 10/16/2019] [Accepted: 11/07/2019] [Indexed: 11/22/2022]
Abstract
The methylotrophic yeast, Ogataea thermomethanolica TBRC656, is an attractive host organism for heterologous protein production owing to the availability of protein expression vectors and a genome-editing tool. In this study, we focused on mating-type switching and gene expression in order to elucidate its sexual life cycle and establish genetic approaches applicable for the strain. A putative mating-type gene cluster was identified in TBRC656 that is syntenic to the cluster in Ogataea parapolymorpha DL-1 (previously named Hansenula polymorpha). Like DL-1, TBRC656 possesses two mating loci, namely MATa and MATα, and also shows flip-flop mating-type switching. Interestingly, unlike any other methylotrophic yeast, TBRC656 robustly switched mating type during late growth in rich medium (YPD). Under nutrient depletion, mating-type switching was observed within one hour. Transcription from both MATa and MATα mating loci was detected during growth in YPD, and possibly induced upon nitrogen depletion. Gene expression from MATα was detected as a single co-transcript from a three-gene array (α2-α1-a1S). Deletion of a putative a1S ORF at the MATα locus had no observed effect on mating-type switching but demonstrated significant effect on mating-type gene expression at both MATa and MATα loci.
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Abstract
The telomere regulator and transcription factor Rap1 is the only telomere protein conserved in yeasts and mammals. Its functional repertoire in budding yeasts is a particularly interesting field for investigation, given the high evolutionary diversity of this group of unicellular organisms. In the methylotrophic thermotolerant species Hansenula polymorpha DL-1 the RAP1 gene is duplicated (HpRAP1A and HpRAP1B). Here, we report the functional characterization of the two paralogues from H. polymorpha DL-1. We uncover distinct (but overlapping) DNA binding preferences of HpRap1A and HpRap1B proteins. We show that only HpRap1B is able to recognize telomeric DNA directly and to protect it from excessive recombination, whereas HpRap1A is associated with subtelomere regions. Furthermore, we identify specific binding sites for both HpRap1A and HpRap1B within promoters of a large number of ribosomal protein genes (RPGs), implicating Rap1 in the control of the RP regulon in H. polymorpha. Our bioinformatic analysis suggests that RAP1 was duplicated early in the evolution of the “methylotrophs” clade, and the two genes evolved independently. Therefore, our characterization of Rap1 paralogues in H. polymorpha may be relevant to other “methylotrophs”, yielding valuable insights into the evolution of budding yeasts.
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12
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Faure G, Jézéquel K, Roisné-Hamelin F, Bitard-Feildel T, Lamiable A, Marcand S, Callebaut I. Discovery and Evolution of New Domains in Yeast Heterochromatin Factor Sir4 and Its Partner Esc1. Genome Biol Evol 2019; 11:572-585. [PMID: 30668669 PMCID: PMC6394760 DOI: 10.1093/gbe/evz010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/20/2019] [Indexed: 12/22/2022] Open
Abstract
Sir4 is a core component of heterochromatin found in yeasts of the Saccharomycetaceae family, whose general hallmark is to harbor a three-loci mating-type system with two silent loci. However, a large part of the Sir4 amino acid sequences has remained unexplored, belonging to the dark proteome. Here, we analyzed the phylogenetic profile of yet undescribed foldable regions present in Sir4 as well as in Esc1, an Sir4-interacting perinuclear anchoring protein. Within Sir4, we identified a new conserved motif (TOC) adjacent to the N-terminal KU-binding motif. We also found that the Esc1-interacting region of Sir4 is a Dbf4-related H-BRCT domain, only present in species possessing the HO endonuclease and in Kluveryomyces lactis. In addition, we found new motifs within Esc1 including a motif (Esc1-F) that is unique to species where Sir4 possesses an H-BRCT domain. Mutagenesis of conserved amino acids of the Sir4 H-BRCT domain, known to play a critical role in the Dbf4 function, shows that the function of this domain is separable from the essential role of Sir4 in transcriptional silencing and the protection from HO-induced cutting in Saccharomyces cerevisiae. In the more distant methylotrophic clade of yeasts, which often harbor a two-loci mating-type system with one silent locus, we also found a yet undescribed H-BRCT domain in a distinct protein, the ISWI2 chromatin-remodeling factor subunit Itc1. This study provides new insights on yeast heterochromatin evolution and emphasizes the interest of using sensitive methods of sequence analysis for identifying hitherto ignored functional regions within the dark proteome.
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Affiliation(s)
- Guilhem Faure
- Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, IRD, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, Paris, France.,National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD
| | - Kévin Jézéquel
- Institut de Biologie François Jacob, IRCM/SIGRR/LTR, INSERM U1274, Université Paris-Saclay, CEA Paris-Saclay, Paris, France.,National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD
| | - Florian Roisné-Hamelin
- Institut de Biologie François Jacob, IRCM/SIGRR/LTR, INSERM U1274, Université Paris-Saclay, CEA Paris-Saclay, Paris, France.,National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD
| | - Tristan Bitard-Feildel
- Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, IRD, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, Paris, France
| | - Alexis Lamiable
- Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, IRD, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, Paris, France
| | - Stéphane Marcand
- Institut de Biologie François Jacob, IRCM/SIGRR/LTR, INSERM U1274, Université Paris-Saclay, CEA Paris-Saclay, Paris, France.,Sorbonne Université, UMR CNRS 7238, IBPS, Laboratoire de Biologie Computationnelle et Quantitative (LCQB), Paris, France
| | - Isabelle Callebaut
- Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, IRD, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, Paris, France.,Sorbonne Université, UMR CNRS 7238, IBPS, Laboratoire de Biologie Computationnelle et Quantitative (LCQB), Paris, France
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