Tighter αC-helix-αL16-helix interactions seem to make p38α less prone to activation by autophosphorylation than Hog1.

ABSTRACT: Many eukaryotic protein kinases (EPKs) are autoactivated through autophosphorylation of their activation loop. Mitogen-activated protein (MAP) kinases do not autophosphorylate spontaneously; relying instead upon mitogen-activated protein kinase (MAPK) kinases (MKKs) for their activation loop phosphorylation. Yet, in previous studies we identified mutations in the yeast MAPK high osmolarity glycerol (Hog1) that render it capable of spontaneous autophosphorylation and consequently intrinsically active (MKK-independent). Four of the mutations occurred in hydrophobic residues, residing in the αC-helix, which is conserved in all EPKs, and in the αL16-helix that is unique to MAPKs. These four residues interact together forming a structural element termed 'hydrophobic core'. A similar element exi

SUBMITTER: Tesker M 

PROVIDER: S-EPMC4847175 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature