Mitogen-activated kinase (MAPK), part of the cell wall integrity (CWI) signaling pathway composed by three protein kinases bck1, mkk2 and mpkA and responsible for the maintaining of cell-wall integrity balance (PubMed:17981060, PubMed:19715768). The CWI pathway regulates also the oxidative stress response, as well as the production of some secondary metabolites including gliotoxin, pyomelanin, pseurotin A, fumiquinazoline C or dihydroxynaphthalene (DHN)-melanin (PubMed:19715768, PubMed:21883519, PubMed:30914505, PubMed:33705521). MpkA directly phosphorylates the fumiquinazoline C biosynthesis cluster nonribosomal peptide synthetase fmqC during conidiation (PubMed:33705521). Mpka is also required for adaptation to iron starvation and regulates the expression of genes involved in siderophore biosynthesis in a hapX/sreA-independent manner (PubMed:21883519). 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. Interacts with the fumiquinazoline C biosynthesis cluster nonribosomal peptide synthetases fmqA and fmqC. Accumulates in the nucleus under iron depletion conditions. Expression is induced by cell wall integrity inhibitors such as glucanex, SDS, congo red and caffeine. Phosphorylated during cell wall stress by the upstream MAPKK mkk2 (PubMed:17981060). Iron starvation triggers phosphorylation and thus activation of mpkA (PubMed:21883519). Phosphorylation increases upon osmotic stress and cell wall damage and depends on mpkC and sakA (PubMed:26878695). Leads to the formation of thicker hyphae, which appear less elongated and form more branched hyphae (PubMed:17981060, PubMed:19715768). Increases sensitivity to diamide and menadione but shows increased tolerance against H(2)O(2) (PubMed:17981060). Results also in increased sensitivity to cell wall integrity inhibitors such as glucanex, SDS, congo red and calcofluor white (PubMed:19715768). Affects the expression of genes involved in cell wall remodeling, protection against ROS, secondary metabolism such as gliotoxin, pyomelanin and pseurotin A, as well as genes involved in siderophore biosynthesis (PubMed:21883519). Affects also the expression of fumiquinazoline C biosynthesis cluster genes (PubMed:33705521). Does not affect the formation of conidiophores and conidia, nor the germination of aconidia (PubMed:17981060). Does not affect the virulence in a low dose murine infection model (PubMed:17981060). Belongs to the protein kinase superfamily. Ser/Thr protein kinase family.