Mitogen-activated protein kinase (MAPK) that plays a role in conidiation and regulation of secondary metabolite biosynthesis (PubMed:30914505). Acts as a repressor of dihydroxynaphthalene (DHN)-melanin production (PubMed:30914505). ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Activated by threonine and tyrosine phosphorylation. Translocates into the nucleus upon exposure to caspofungin stress, and this is dependent on the cross-talk interaction with mpkA. Leads to a strong increase of dihydroxynaphthalene (DHN)-melanin production (PubMed:30914505). Results in about 3-fold less glucosamine and a lower level of alpha-linked mannose within the cell wall (PubMed:30914505). Does not affect virulence (PubMed:30914505). Belongs to the protein kinase superfamily. Ser/Thr protein kinase family. MAP kinase subfamily.