Mitogen-activated protein kinase 4 is an enzyme that in humans is encoded by the MAPK4gene.
Mitogen-activated protein kinase 4 is a member of the mitogen-activated protein kinase family. Tyrosine kinase growth factor receptors activate mitogen-activated protein kinases which then translocate into the nucleus where it phosphorylates nuclear targets.
The Arabidopsis MAPK4 is important in signalling 
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