In nature, Saccharomyces yeasts manifest a number of adaptive responses to overcome adverse environments such as filamentation, invasive growth, flocculation and adherence solid surfaces. Certain wild yeasts, namely “flor yeasts,” have also acquired the ability form buoyant biofilm at broth surface. Here we report that mutations in single gene, identified FLO11 , separate these “floating” from their nonfloating relatives. We determined capability self-supporting liquid surface is largely...

Transcriptionally silent chromatin localizes to the nuclear periphery, which provides a special microenvironment for gene repression. A variety of membrane proteins interact with repressed chromatin, yet functional role these interactions remains poorly understood. Here, we show that, in Schizosaccharomyces pombe , protein Lem2 associates and mediates silencing heterochromatin localization. Unexpectedly, found that functions can be separated assigned different structural domains within Lem2,...

Heterochromatin plays important roles in eukaryotic genome regulation. However, the repressive nature of heterochromatin combined with its propensity to self-propagate necessitates robust mechanisms contain within defined boundaries and thus prevent silencing expressed genes. Here we show that loss PAF complex (PAFc) component Leo1 compromises chromatin boundaries, resulting invasion into flanking euchromatin domains. Similar effects are seen upon deletion other PAFc components, but not...

Fungal pathogenesis depends on accurate secretion and location of virulence factors which drive host colonization. Protein glycosylation is a common posttranslational modification cell wall components other secreted factors, typically required for correct protein localization, function. Thus, the absence associated with animal plant pathogen avirulence. While relevance has been well established, main glycoproteins responsible loss observed in glycosylation-defective fungi have not...

Adhesins play a central role in the cellular response of eukaryotic microorganisms to their host environment. In pathogens such as Candida spp. and other fungi, adhesins are responsible for adherence mammalian tissues, Saccharomyces yeasts also confer solid surfaces yeast cells. The analysis FLO11, main adhesin identified cerevisiae, has revealed complex mechanisms, involving both genetic epigenetic regulation, governing expression this critical gene. We designed genomewide screen identify...

Abstract In Saccharomyces yeasts, the FLO11 gene encodes an adhesin involved in filamentation, invasive growth, flocculation and adherence to solid surfaces. wild flor a particularly expanded allele also confers these yeasts ability float under stressing liquid environments. We report here that, optimal laboratory conditions, repeats domain of is extremely unstable. Changes length coding affected Flo11p‐associated functions but, interestingly, some were more than others. Therefore,...

Abstract Transcriptionally silent chromatin often localizes to the nuclear periphery. However, whether envelope (NE) is a site for post-transcriptional gene repression not well understood. Here we demonstrate that Schizosaccharomyces pombe Lem2, an NE protein, regulates nuclear-exosome-mediated RNA degradation. Lem2 deletion causes accumulation of precursors and meiotic transcripts de-localization engineered exosome substrate from does directly bind but instead interacts with...

Heterochromatin spreading, the expansion of repressive chromatin structure from sequence-specific nucleation sites, is critical for stable gene silencing. Spreading re-establishes gene-poor constitutive heterochromatin across cell cycles but can also invade gene-rich euchromatin de novo to steer fate decisions. How context (i.e. euchromatic, heterochromatic) or different pathways influence spreading remains poorly understood. Previously, we developed a single-cell sensor in fission yeast...

Cell adhesion and biofilm formation are critical processes in the pathogenicity of fungi mediated through a family adhesin proteins conserved throughout yeasts fungi. In Saccharomyces cerevisiae, Flo11 is main involved cell formation, making study its function regulation this nonpathogenic budding yeast highly relevant. The S. cerevisiae FLO11 gene driven by TATA-box-containing promoter that regulated one longest regulatory upstream regions (3 kb) yeast. We reported recently two chromatin...

Plant pathogenic fungi must be able to degrade host cell walls in order penetrate and invade plant tissues. Among the wall degrading enzymes (PCWDEs) produced, xylanases are of special interest since its degradation target, xylan, is one main structural polysaccharides walls. In biotrophic fungus Ustilago maydis, attempts characterize PCWDEs required for virulence have been unsuccessful, most likely due functional redundancy. previous high-throughput screening, we found xylanase important U....

Adaptation to the environment is a requirement for survival of every organism. For pathogenic fungi this also implies coping with different conditions that occur during infection cycle. After detecting changes external media, organisms must modify their gene expression patterns in order accommodate new circumstances. Control complex process involves coordinated action multiple regulatory elements. Chromatin modification well-known mechanism controlling response environmental all eukaryotes....

Protection of euchromatin from invasion by gene-repressive heterochromatin is critical for cellular health and viability. In addition to constitutive loci such as pericentromeres subtelomeres, can be found interspersed in gene-rich euchromatin, where it regulates gene expression pertinent cell fate. While are globally poised mutual antagonism, the mechanisms underlying precise spatial encoding containment within euchromatic sites remain opaque. We investigated ectopic manipulating fission...

Phytopathogenic fungi must adapt to the different environmental conditions found during infection and avoid immune response of plant. For these adaptations, tightly control gene expression, allowing sequential changes in transcriptional programs. In addition transcription factors, chromatin modification is used by eukaryotic cells as a layer control. Specifically, acetylation histones one modifications with strong impact on expression. Hyperacetylated regions usually correlate high...

Kinetochores (KTs) are large multiprotein complexes that constitute the interface between centromeric chromatin and mitotic spindle during chromosome segregation. In spite of their essential role, little is known about how centromeres KTs assembled precise stoichiometry regulated. this study, we show nuclear pore basket component Alm1 required to maintain both proteasome its anchor, Cut8, at envelope, which in turn regulates proteostasis certain inner KT components. Consistently,...

Abstract Fungal pathogenesis depends on accurate secretion and location of virulence factors which drive host colonization. Protein glycosylation is a common posttranslational modification cell wall components other secreted factors, typically required for correct protein localization, function. Thus, the absence associated with animal plant pathogen avirulence. While relevance has been well established, main glycoproteins responsible loss observed in glycosylation-defective fungi have not...

Heterochromatin plays a critical role in regulating gene expression and maintaining genome integrity. While structural enzymatic components have been linked to heterochromatin establishment, comprehensive view of the underlying pathways at diverse domains remains elusive. Here, we developed systematic approach identify factors involved silencing pericentromeres, subtelomeres, silent mating type locus

The appressorium of phytopathogenic fungi is a specific structure with crucial role in plant cuticle penetration. Pathogens melanized appressoria break the through cell wall melanization and intracellular turgor pressure. However, nonmelanized appressorium, mechanisms governing penetration are poorly understood. Here we characterize Row1, previously uncharacterized appressoria-specific protein Ustilago maydis that localizes to membrane secretory vesicles. Deletion row1 decreases formation...

Abstract Heterochromatin plays a critical role in regulating gene expression and maintaining genome integrity. While structural enzymatic components have been linked to heterochromatin establishment, comprehensive view of the underlying pathways at diverse domains remains elusive. Here, we developed systematic approach identify factors involved silencing pericentromeres, subtelomeres silent mating type locus Schizosaccharomyces pombe. Using quantitative measures, iterative genetic screening...

ABSTRACT Protection of euchromatin from invasion by gene-repressive heterochromatin is critical for cellular health and viability. In addition to constitutive loci such as pericentromeres subtelomeres, can be found interspersed in gene-rich euchromatin, where it regulates gene expression pertinent cell fate. While hetero- are globally poised mutual antagonism, the mechanisms underlying precise spatial encoding containment within euchromatic sites remain opaque. We investigated ectopic...

ABSTRACT Heterochromatin spreading, the expansion of gene-silencing structures from DNA-encoded nucleation sites, occurs in distinct settings. Spreading re-establishes gene-poor constitutive heterochromatin every cell cycle, but also invades gene-rich euchromatin de novo to steer fate decisions. How chromatin context, i.e. euchromatic, heterochromatic, or different nucleator types, influences determinants this process remains poorly understood. By screening a nuclear function gene deletion...