title: Muc1, a mucin-like protein that is regulated by Mss10, is critical for pseudohyphal differentiation in yeast.
abstract: Pseudohyphal differentiation in Saccharomyces cerevisiae was first described as a response of diploid cells to nitrogen limitation. Here we report that haploid and diploid starch-degrading S. cerevisiae strains were able to switch from a yeast form to a filamentous pseudohyphal form in response to carbon limitation in the presence of an ample supply of nitrogen. Two genes, MSS10 and MUC1, were cloned and shown to be involved in pseudohyphal differentiation and invasive growth. The deletion of MSS10 resulted in extremely reduced amounts of pseudohyphal differentiation and invasive growth, whereas the deletion of MUC1 abolished pseudohyphal differentiation and invasive growth completely. Mss10 appears to be a transcriptional activator that responds to nutrient limitation and coregulates the expression of MUC1 and the STA1-3 glucoamylase genes, which are involved in starch degradation. MUC1 encodes a 1367-amino acid protein, containing several serine/threonine-rich repeats. Muc1 is a putative integral membrane-bound protein, similar to mammalian mucin-like membrane proteins that have been implicated to play a role in the ability of cancer cells to invade other tissues.
authors.affiliation: Department of Microbiology, University of Stellenbosch, South Africa.
authors.forename: M G
authors.initials: MG
authors.lastname: Lambrechts
authors.forename: F F
authors.initials: FF
authors.lastname: Bauer
authors.forename: J
authors.initials: J
authors.lastname: Marmur
authors.forename: I S
authors.initials: IS
authors.lastname: Pretorius
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002244:Carbon / Q000378:metabolism; D002454:Cell Differentiation; D003001:Cloning, Molecular; D017931:DNA Primers / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000502:physiology*; D004171:Diploidy; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D006238:Haploidy; D017874:Immediate-Early Proteins; D008969:Molecular Sequence Data; D018396:Mucin-1 / Q000235:genetics*; D009077:Mucins; D016254:Mutagenesis, Insertional; D012333:RNA, Messenger / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure*; D029701:Saccharomyces cerevisiae Proteins; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013213:Starch / Q000378:metabolism; D014157:Transcription Factors; D014158:Transcription, Genetic
chemical_list: D017931:DNA Primers; D004268:DNA-Binding Proteins; D017874:Immediate-Early Proteins; C490188:MSN1 protein, S cerevisiae; D018396:Mucin-1; D009077:Mucins; D012333:RNA, Messenger; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D002244:Carbon; D013213:Starch