Characterization of four septin genes, and detection of genetic interactions between WdCDC10 and chitin synthase genes during yeast budding in the polymorphic mold, Wangiella (Exophiala) dermatitidis

dc.contributor.advisorSzaniszlo, Paul J.
dc.creatorPark, Changwonen
dc.date.accessioned2015-04-28T22:05:48Zen
dc.date.accessioned2018-01-22T22:27:44Z
dc.date.available2015-04-28T22:05:48Zen
dc.date.available2018-01-22T22:27:44Z
dc.date.issued2007-08en
dc.descriptiontexten
dc.description.abstractSeptins are a highly conserved family of eukaryotic proteins having significant homology within and among species. In the budding yeast, Saccharomyces cerevisiae, a septin-based hierarchy of proteins is required to localize chitin in the bud neck prior to septum formation. However, this process has not been clarified in a filamentous, conidiogenous fungus capable of yeast growth, such as Wangiella dermatitidis, a polymorphic agent of human phaeohyphomycosis. Prior studies of this melanized mold showed that some chitin synthase mutants (wdchsΔ) have defects in yeast septum formation, suggesting that the septins of W. dermatitidis might functionally associate with some of its chitin synthases (WdChsp). To test this hypothesis, four vegetative septin homologs of S. cerevisiae were cloned from W. dermatitidis and designated WdCDC3, WdCDC10, WdCDC11, and WdCDC12. Of the four, only WdCDC3 functionally complemented completely a strain of S. cerevisiae with a ts mutation in the corresponding gene, although WdCDC12 did so partially. Functional characterizations by mutagenesis of the four W. dermatitidis septin genes revealed that resulting mutants (wdcdc[delta]) each had unique defects in yeast growth and morphology, indicating that each septin carried out a distinct function. Furthermore, when a wdcdc10[delta] mutation was introduced into five different wdchs[delta] strains, weak genetic interactions were detected between WdCDC10 and WdCHS3 and WdCHS4, and a strong interaction between and WdCHS5. Cytological studies showed that WdChs5p was mislocalized in some septin mutants, including wdcdc10[delta]. These results confirmed that in W. dermatitidis septins are important for proper cellular morphogenesis, cytokinesis, and especially septum formation through associations with some chitin synthases.en
dc.description.departmentMicrobiologyen
dc.format.mediumelectronicen
dc.identifier.urihttp://hdl.handle.net/2152/29649en
dc.language.isoengen
dc.rightsCopyright is held by the author. Presentation of this material on the Libraries' web site by University Libraries, The University of Texas at Austin was made possible under a limited license grant from the author who has retained all copyrights in the works.en
dc.subjectSeptin genesen
dc.subjectGenetic interactionsen
dc.subjectWdCDC10en
dc.subjectChitin synthase genesen
dc.subjectYeast buddingen
dc.subjectWangiella (Exophiala) dermatitidisen
dc.titleCharacterization of four septin genes, and detection of genetic interactions between WdCDC10 and chitin synthase genes during yeast budding in the polymorphic mold, Wangiella (Exophiala) dermatitidisen
dc.typeThesisen

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