Repression of hyphal proteinase expression by the mitogen-activated protein (MAP) kinase phosphatase Cpp1p of Candida albicans is independent of the MAP kinase Cek1p.
Cpp1p is a putative mitogen-activated protein (MAP) kinase phosphatase that suppresses Candida albicans hyphal formation at 25 degrees C through its probable substrate, the Cek1p filamentation MAP kinase. Here we report that expression of the serum-induced genes SAP4-6 and HYR1 increased several fold in hyphal forms of a cpp1/cpp1 null mutant, while the rate and extent of hyphal development up to 5 h were normal. Therefore, we provide evidence that Cpp1p represses hyphal gene expression by acting through a Cek1p-independent mechanism. SAP4-6 and HYR1 transcripts were undetectable in a null mutant of another key regulator of filamentation, Efg1p; thus, Efg1p and Cpp1p oppose each other during the expression of these genes in hyphal forms.
Schröppel
K
K
Institute of Clinical Microbiology, Immunology and Hygiene, University of Erlangen, 91054 Erlangen, Germany. klaus.schroeppel@mikrobio.med.unierlangen.de
Sprösser
K
K
Whiteway
M
M
Thomas
D Y
DY
Röllinghoff
M
M
Csank
C
C
D016282:Aspartic Acid Endopeptidases / Q000235:genetics*; D002176:Candida albicans / Q000201:enzymology* / Q000235:genetics; D004268:DNA-Binding Proteins; D005656:Fungal Proteins / Q000235:genetics* / Q000502:physiology*; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000502:physiology*; D017027:Protein Tyrosine Phosphatases / Q000502:physiology*; D012333:RNA, Messenger / Q000032:analysis; D012097:Repressor Proteins / Q000502:physiology*; D014157:Transcription Factors
D004268:DNA-Binding Proteins; C121438:EFG1 protein, Candida albicans; D005656:Fungal Proteins; C101636:HYR1 protein, Candida albicans; D012333:RNA, Messenger; D012097:Repressor Proteins; D014157:Transcription Factors; C077339:CEK1 protein, Candida albicans; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D017027:Protein Tyrosine Phosphatases; D016282:Aspartic Acid Endopeptidases; C086392:SAP4 protein, Candida albicans; C090755:SAP5 protein, Candida albicans