Transcript profiling of a MAP kinase pathway in C. albicans.

Area of Science:

• Microbiology
• Molecular Biology
• Cell Biology

Background:

• MAP kinase pathways regulate fungal development.
• In Candida albicans, hyphal development is crucial for virulence.
• The transcription factor Cph1p and its upstream kinases are potential regulators of this process.

Purpose of the Study:

• To investigate the roles of Cph1p, Cst20p, Hst7p, and Cek1p in Candida albicans filamentation.
• To analyze the transcription profiles associated with the yeast-hyphal transition under different genetic conditions.
• To elucidate the regulatory relationship between Cph1p and the Cek1p-Hst7p-Cst20p pathway.

Main Methods:

• Gene deletion and overexpression in Candida albicans.
• Transcriptional profiling using microarrays or RNA-Seq.
• Analysis of fungal morphology and filamentation assays.

Main Results:

• Deletion of CPH1, CST20, HST7, or CEK1 did not abolish serum-induced filamentation.
• CPH1 deletion caused a delay in filamentation, while CPH1 overexpression enhanced it.
• Overexpression of CPH1 under yeast conditions mimicked the transcriptional profile of the yeast-hyphal transition.
• Cek1p, Hst7p, and Cst20p appear to repress genes like CHT2 independently of Cph1p.

Conclusions:

• Cph1p plays a significant, but not essential, role in Candida albicans filamentation.
• The Cek1p-mediated pathway regulates specific gene repression distinct from Cph1p's function.
• Understanding these pathways provides insights into the complex regulation of fungal morphogenesis.