Budding Yeast (budding + yeast)

Distribution by Scientific Domains

Terms modified by Budding Yeast

  • budding yeast saccharomyces cerevisiae

  • Selected Abstracts

    Non-core subunit eIF3h of translation initiation factor eIF3 regulates zebrafish embryonic development

    Avik Choudhuri
    Abstract Eukaryotic translation initiation factor eIF3, which plays a central role in translation initiation, consists of five core subunits that are present in both the budding yeast and higher eukaryotes. However, higher eukaryotic eIF3 contains additional (non-core) subunits that are absent in the budding yeast. We investigated the role of one such non-core eIF3 subunit eIF3h, encoded by two distinct genes,eif3ha and eif3hb, as a regulator of embryonic development in zebrafish. Both eif3h genes are expressed during early embryogenesis, and display overlapping yet distinct and highly dynamic spatial expression patterns. Loss of function analysis using specific morpholino oligomers indicates that each isoform has specific as well as redundant functions during early development. The morphant phenotypes correlate with their spatial expression patterns, indicating that eif3h regulates development of the brain, heart, vasculature, and lateral line. These results indicate that the non-core subunits of eIF3 regulate specific developmental programs during vertebrate embryogenesis. Developmental Dynamics 239:1632,1644, 2010. © 2010 Wiley-Liss, Inc. [source]

    Identification and functional analysis of the gene for type I myosin in fission yeast

    GENES TO CELLS, Issue 3 2001
    Mika Toya
    Background Type I myosin is highly conserved among eukaryotes, and apparently plays important roles in a number of cellular processes. In the budding yeast, two myosin I species have been identified and their role in F-actin assembly has been inferred. Results We cloned the fission yeast myo1 gene, which apparently encoded a myosin I protein. Disruption of myo1 was not lethal, but it caused growth retardation at high and low temperatures, sensitivity to a high concentration of KCl, and aberrance in cell morphology associated with an abnormal distribution of F-actin patches. An abnormal deposition of cell wall materials was also seen. Homothallic myo1, cells could mate, but heterothallic myo1, cells were poor in conjugation. Myo1p was necessary for the encapsulation of spores. The tail domain of Myo1p was pivotal for its function. Calmodulin could bind to Myo1p through the IQ domain at the neck. Conclusions Myo1p appears to control the redistribution of F-actin patches during the cell cycle. Loss of Myo1p function is likely to slow down the actin assembly/disassembly process, which results in a failure of the actin cycle to catch up with other events in both the mitotic and meiotic cell cycles, including extension of the conjugation tubes. [source]

    Functional analysis of the C-terminal cytoplasmic region of the M-factor receptor in fission yeast

    GENES TO CELLS, Issue 3 2001
    Kouji Hirota
    Background Yeast mating-pheromone receptors facilitate the study of G protein-coupled signal transduction. To date, molecular dissection of the budding yeast ,-factor receptor has been done extensively, but little analysis has been performed with pheromone receptors of fission yeast, another genetically tractable yeast species. Results We analysed the fission yeast M-factor receptor Map3p. Truncation of the C-terminal 54 amino acids made Map3p dominant-negative over the wild-type. This form, called Map3-dn9p, was competent in the induction of pheromone-dependent gene expression, although it could not direct proper conjugation. Map3-dn9p failed both to provoke the orientated projection of conjugation tubes and to induce adaptation to the pheromone signal associated with endocytosis of the receptor. Deletion and substitution analyses suggested that the integrity of the C-terminal region, rather than a specific subgroup of amino acid residues therein, was vital for the respective Map3p activities. Ubiquitination of the C-terminus was not absolutely essential for Map3p function. Conclusions The C-terminal region of Map3p is dispensable for the pheromone signalling per se, but is pivotal for adaptation and pheromone-induced conjugation tube formation, as is true with the budding yeast ,-factor receptor. However, the mechanisms which induce adaptation appear to differ between fission and budding yeast concerning the necessity of ubiquitination. [source]

    Cell cycle mechanisms of sister chromatid separation; Roles of Cut1/separin and Cut2/securin

    GENES TO CELLS, Issue 1 2000
    Mitsuhiro Yanagida
    The correct transmission of chromosomes from mother to daughter cells is fundamental for genetic inheritance. Separation and segregation of sister chromatids in growing cells occurs in the cell cycle stage called ,anaphase'. The basic process of sister chromatid separation is similar in all eukaryotes: many gene products required are conserved. In this review, the roles of two proteins essential for the onset of anaphase in fission yeast, Cut2/securin and Cut1/separin, are discussed with regard to cell cycle regulation, and compared with the postulated roles of homologous proteins in other organisms. Securin, like mitotic cyclins, is the target of the anaphase promoting complex (APC)/cyclosome and is polyubiquitinated before destruction in a manner dependent upon the destruction sequence. The anaphase never occurs properly in the absence of securin destruction. In human cells, securin is an oncogene. Separin is a large protein (MW ,180 kDa), the C-terminus of which is conserved, and is thought to be inhibited by association with securin at the nonconserved N-terminus. In the budding yeast, Esp1/separin is thought to be a component of proteolysis against Scc1, an essential subunit of cohesin which is thought to link duplicated sister chromatids up to the anaphase. Whether fission yeast Cut1/separin is also implicated in proteolysis of cohesin is discussed. [source]

    Polymerization of the SAM domain of MAPKKK Ste11 from the budding yeast: Implications for efficient signaling through the MAPK cascades

    PROTEIN SCIENCE, Issue 3 2005
    Surajit Bhattacharjya
    Abstract The sterile ,-motif (SAM) is a protein module ,70 residues long and mainly involved in the protein,protein interactions of cell signaling and transcriptional repression. The SAM domain of the yeast MAPKKK Ste11 has a well-folded dimeric structure in solution. Interestingly, the well-folded dimer of the Ste11 SAM undergoes a time-dependent self-assembly upon lowering of the pH, leading to the formation of high molecular weight oligomers. The oligomeric structures rapidly disassemble to the well-folded dimer upon reversal of the pH to close to neutral conditions. Circular dichroism (CD) and atomic force microscopy (AFM) experiments demonstrate that the oligomeric structure formed at pH 5.0 appears to be highly helical and has architecture akin to proto-fibrils. Residue-specific kinetics of pH-triggered oligomerization obtained from real-time 15N- 1H HSQC experiments indicate that the dimer-oligomer transition appears to involve all residues of the well-folded dimeric structure of the Ste11 SAM. Very interestingly, the interactions of the Ste11 and Ste50 SAM domains also lead to the formation of non-homogeneous hetero-complexes with significant populations of high molecular weight aggregates. AFM imaging shows that the Ste11-Ste50 hetero-polymeric aggregates assume the shapes of circular nano-particles with dimensions of 50,60 nano-meters (nm), in contrast to the proto-fibrils formed by the Ste11 SAM domain alone. Such intrinsic propensity for dimer to oligomer transition of the Ste50-binding SAM domain of Ste11 may endow the MAPKKK Ste11 with unique functional properties required for efficient and high fidelity signal transduction in the budding yeast. [source]

    Using budding yeast to screen for anti-prion drugs

    Déborah Tribouillard
    Abstract Prions are misfolded proteins capable of propagating their altered conformation which are commonly considered as the causative agent of transmissible spongiform encephalopathies, a class of fatal neurodegenerative diseases. Currently, no treatment for prion-based diseases is available. Recently we have developed a rapid, yeast-based, two-step assay to screen for anti-prion drugs [1]. This new method allowed us to identify several compounds that are effective in vivo against budding yeast [PSI+] and [URE3] prions but also able to promote mammalian prion clearance in three different cell culture-based assays. Taken together, these results validate our method as an economic and efficient high-throughput screening approach to identify novel prion inhibitors or to carry on comprehensive structure-activity studies for already isolated anti-mammalian prion drugs. These results suggest furthermore that biochemical pathways controlling prion formation and/or maintenance are conserved from yeast to human and thus amenable to pharmacological and genetic analysis. Finally, it would be very interesting to test active drugs isolated using the yeast-based assay in models for other diseases (neurodegenerative or not) involving amyloid fibers like Huntington's, Parkinson's or Alzheimer's diseases. [source]