RESUMO
To obtain a comprehensive understanding of the budding phase transition, 4,711 Saccharomyces cerevisiae haploid nonessential gene deletion mutants were screened with the image processing program CalMorph, and 35 mutants with a round bud and 173 mutants with an elongated bud were statistically identified. We classified round and elongated bud mutants based on factors thought to affect the duration of the apical bud growth phase. Two round bud mutants (arc18 and sac6) were found to be defective in apical actin patch localization. Several elongated bud mutants demonstrated a delay of cell cycle progression at the apical growth phase, suggesting that these mutants have a defect in the control of cell cycle progression.
Assuntos
Deleção de Genes , Genes Fúngicos , Glicoproteínas de Membrana/metabolismo , Proteínas dos Microfilamentos/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/genética , Actinas/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Polaridade Celular/genética , Expressão Gênica , Haploidia , Glicoproteínas de Membrana/genética , Proteínas dos Microfilamentos/genética , Saccharomyces cerevisiae/citologia , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismoRESUMO
In the course of our screening program for active compounds that induce cell morphological changes of Saccharomyces cerevisiae, the culture broth of an entomopathogenic fungus Metarhizium sp. fE61 exhibited a unique morphological phenotype. We conducted an activity-guided isolation from the fermentation broth of Metarhizium sp. fE61 to yield two new macrolide compounds named JBIR-19 (1) and -20 (2) as active substances. Their structures were determined to be 24-membered macrolide analogs containing a 2-aminoethyl phosphate ester on the basis of NMR and other spectroscopic data. Compounds 1 and 2 induced striking elongated morphology of S. cerevisiae at concentrations of 3.1 and 13 microM, but showed weak antiyeast activity at MICs of 200 and >200 microM, respectively.
Assuntos
Antifúngicos/biossíntese , Macrolídeos/metabolismo , Metarhizium/metabolismo , Antifúngicos/química , Antifúngicos/farmacologia , Cromatografia Líquida de Alta Pressão , Meios de Cultura , Fermentação , Macrolídeos/química , Macrolídeos/farmacologia , Espectroscopia de Ressonância Magnética , Metarhizium/classificação , Saccharomyces cerevisiae/efeitos dos fármacos , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho , Espectrofotometria UltravioletaRESUMO
One of the most powerful techniques for attributing functions to genes in uni- and multicellular organisms is comprehensive analysis of mutant traits. In this study, systematic and quantitative analyses of mutant traits are achieved in the budding yeast Saccharomyces cerevisiae by investigating morphological phenotypes. Analysis of fluorescent microscopic images of triple-stained cells makes it possible to treat morphological variations as quantitative traits. Deletion of nearly half of the yeast genes not essential for growth affects these morphological traits. Similar morphological phenotypes are caused by deletions of functionally related genes, enabling a functional assignment of a locus to a specific cellular pathway. The high-dimensional phenotypic analysis of defined yeast mutant strains provides another step toward attributing gene function to all of the genes in the yeast genome.
