The CEK1-mediated mitogen-activated protein kinase pathway in the fungal pathogen Candida albicans

Mitogen-activated protein kinases (MAPK) mediated signal transduction pathways are essential for the adaptation of living organisms to environmental changes. In pathogenic fungi, these MAPK cascades govern the response to many types of situations, and are essential for the successful establishment of the fungus within the host. Therefore, they influence virulence and can be considered as promising therapeutic targets. In the opportunistic pathogen Candida albicans, the Cek1-mediated pathway was identified long time ago as an important virulence determinant in certain animal models. We will review here the recent work that reveals the role that this route plays in three important processes for the cell: osmotic adaptation, fungal morphogenesis and cell wall remodeling. We will also show the complementary (and sometimes opposite) roles that under specific circumstances the high osmolarity glycerol and CEK1 pathways play in C. albicans biology, especially in the context of the interaction with the mammalian host.