A screen in Saccharomyces cerevisiae identified CaMCM1, an essential gene in Candida albicans crucial for morphogenesis.
Morphogenesis in Saccharomyces cerevisiae and the pathogenic yeast Candida albicans is governed in part by the same molecular circuits. In S. cerevisiae, FLO11/MUC1 expression has been shown to be modulated by multiple signalling pathways required for pseudohyphal development. We have established a screen in S. cerevisiae to identify regulators of fungal development in C. albicans based on FLO11::lacZ expression as a reporter. This screen identified both known components of the mitogen-activated protein kinase (MAPK) cascade and the cAMP cascade that are important for hyphal development in C. albicans, as well as genes not yet known to be involved in morphogenesis. The Candida homologue of MCM1 is one of the novel factors identified in this screen as being important for morphogenesis. CaMcm1p levels do not vary significantly in different cell types and respond to an autoregulatory feedback mechanism, arguing that CaMcm1p activity is regulated by post-translational modifications. Both overexpression and repression of this essential gene led to the induction of hyphae. Moreover, we found that the expression of HWP1, a hyphae-specific gene, was induced by repression of CaMCM1. The changes in morphology and HWP1 expression were not the result of a change in expression levels of NRG1 or TUP1, known repressors of hyphal development. Thus, CaMcm1p is a component of a hitherto unknown regulatory mechanism of hyphal growth.
Rottmann
M
M
Fraunhofer IGB, Nobelstr. 12, 70569 Stuttgart, Germany.
Dieter
S
S
Brunner
H
H
Rupp
S
S
D001483:Base Sequence; D002176:Candida albicans / Q000235:genetics* / Q000254:growth & development* / Q000378:metabolism; D002448:Cell Adhesion; D004271:DNA, Fungal / Q000235:genetics; D004268:DNA-Binding Proteins; D005656:Fungal Proteins / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D017930:Genes, Reporter; D005816:Genetic Complementation Test; D007763:Lac Operon; D008562:Membrane Glycoproteins / Q000235:genetics; D008565:Membrane Proteins / Q000235:genetics; D026341:Minichromosome Maintenance 1 Protein / Q000235:genetics*; D009024:Morphogenesis / Q000235:genetics; D009687:Nuclear Proteins / Q000235:genetics; D012331:RNA, Fungal / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics
D004271:DNA, Fungal; D004268:DNA-Binding Proteins; C110690:FLO11 protein, S cerevisiae; D005656:Fungal Proteins; C118102:HWP1 protein, Candida albicans; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D026341:Minichromosome Maintenance 1 Protein; C117881:NRG1 protein, S cerevisiae; D009687:Nuclear Proteins; D012331:RNA, Fungal; D012333:RNA, Messenger; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; C066502:TUP1 protein, S cerevisiae