Mitogen Activated Protein Kinase 4 (MAPK4)

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.

Of the 4, 2 probably resulted from alternative processing of transcripts from a single gene. Zhu et al. (1994) stated that p63MAPK, which had been known as ERK3, shares only 73% protein sequence identity with rat ERK3. They suggested that p97MAPK (MAPK6) is the true ERK3 homolog, and that p63MAPK is a member of the ERK3 subfamily. Garcia et al. (1996) reported that a gene they referred to as MNK2 is the rat homolog of p63MAPK. The 2 protein sequences are 95% identical.