Serine/threonine protein kinase component of the cell integrity pathway, a signal transduction pathway that plays a role in yeast cell morphogenesis and cell growth. Participates in cell wall construction, azole resistance, and host interaction. Required for the signaling for invasive filamentous growth and biofilm formation, and plays a crucial role in virulence. ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Expression is up-regulated by caspofungin. The TXY motif contains the threonine and tyrosine residues whose phosphorylation activates the MAP kinases. Activated through phosphorylation of Thr-211 and Tyr-213 from the TXY motif (By similarity). Phosphorylated in a PKC1-dependent manner in response to cell wall perturbations, oxidative stress, osmotic stress, and low temperatures. Also activated in response to physical contact leading to contact-dependent cellular behaviors such as invasive hyphal growth and biofilm development. Phosphorylation is also PBS2- and HOG1-dependent. Leads to thermosensitive growth, enhanced caffeine and caspofungin sensitivity, and alterations of cell surfaces. Leads also to a decreased pathogenicity in mice through displaying a greater susceptibility to nitric oxide (NO), a reduced inhibitory effect on macrophage NO production, and an increased capacity of macrophage stimulation by cell wall extracts. Belongs to the protein kinase superfamily. CMGC Ser/Thr protein kinase family. MAP kinase subfamily.