protein phosphatase 1 regulatory subunit 12A; myosin phosphatase-targeting subunit 1; myosin phosphatase target subunit 1; protein phosphatase myosin-binding subunit (PPP1R12A, MBS, MYPT1)

Function

• regulatory subunit of protein phosphatase 1 (PP1)
• regulates myosin phosphatase activity
• phosphorylated by CIT (Rho-associated kinase)
• phosphorylated cooperatively by ROCK1 & CDC42BP on Thr-696
• phosphorylated on upon DNA damage, probably by ATM or ATR
• in vitro, phosphorylation of Ser-695 by PKA & PKG appears to prevent phosphorylation of the inhibitory site Thr-696, probably mediated by PRKG1
• interacts with ARHA & CIT (putative)
• binds PPP1R12B, ROCK1 & IL16
• interacts directly with PRKG1. non-covalent dimer of 2 dimers; PRKG1-PRKG1 & PPP1R12A-PPP1R12A

Structure

• heterotetramerization is mediated by interaction between a coiled-coil of PRKG1 & the leucine/isoleucine zipper of PPP1R12A/MBS, the myosin-binding subunit of myosin phosphatase (putative)
• contains 6 ANK repeats

Compartment

• cytoplasm
• long actomyosin filaments & stress fibers

Alternative splicing

named isoforms=4

More general terms

• protein phosphatase-1 regulatory subunit
• ankyrin repeat domain protein (ANKRD)
• phosphoprotein

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=4659
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:4659
• OMIM: https://mirror.omim.org/entry/602021
• UniProt: http://www.uniprot.org/uniprot/O14974.html