The Candida albicans CaACE2 gene affects morphogenesis, adherence and virulence

Area of Science:

• Microbiology
• Molecular Biology
• Cell Biology

Background:

• Morphogenesis, including yeast and hyphal growth, is critical for Candida albicans virulence and involves cell wall alterations.
• In Saccharomyces cerevisiae, Ace2p and Swi5p transcription factors regulate cell wall metabolism.
• CaACE2 is the sole C. albicans homologue of S. cerevisiae ACE2 and SWI5.

Purpose of the Study:

• To characterize the function of the CaACE2 gene in Candida albicans.
• To investigate the role of CaAce2p in morphogenesis, cell adherence, biofilm formation, and virulence.

Main Methods:

• Gene deletion of CaACE2 in C. albicans.
• Phenotypic analysis of the CaACE2 deletion mutant, including cell separation, invasion, and pseudohyphal growth.
• Assessment of cell adherence to plastic surfaces and biofilm morphology.
• Evaluation of virulence in a mouse model.
• Analysis of cell wall gene expression (CHT2, CHT3, CaDSE1, CaSCW11).
• Subcellular localization of CaAce2 protein.

Main Results:

• CaACE2 deletion resulted in defective cell separation, increased agar invasion, and spontaneous pseudohyphal growth.
• Mutant cells showed reduced adherence to plastic and formed biofilms with altered morphology.
• The CaACE2 deletion mutant was avirulent in a mouse model.
• CaACE2 deletion did not affect CHT2 expression but reduced CHT3, CaDSE1, and CaSCW11 expression.
• CaAce2 protein localized to the daughter nucleus during mitosis.

Conclusions:

• CaAce2p is a crucial regulator of morphogenesis and adherence in Candida albicans.
• CaAce2p plays a significant role in C. albicans virulence and biofilm development.
• The function of CaAce2p in C. albicans is analogous to that of S. cerevisiae Ace2p.