PPP1CB

Function

Protein phosphatase that associates with over 200 regulatory proteins to form highly specific holoenzymes which dephosphorylate hundreds of biological targets. Protein phosphatase (PP1) is essential for cell division, it participates in the regulation of glycogen metabolism, muscle contractility and protein synthesis. Involved in regulation of ionic conductances and long-term synaptic plasticity. Component of the PTW/PP1 phosphatase complex, which plays a role in the control of chromatin structure and cell cycle progression during the transition from mitosis into interphase. In balance with CSNK1D and CSNK1E, determines the circadian period length, through the regulation of the speed and rhythmicity of PER1 and PER2 phosphorylation. May dephosphorylate CSNK1D and CSNK1E. Dephosphorylates the 'Ser-418' residue of FOXP3 in regulatory T-cells (Treg) from patients with rheumatoid arthritis, thereby inactivating FOXP3 and rendering Treg cells functionally defective (PubMed:23396208). Core component of the SHOC2-MRAS-PP1c (SMP) holophosphatase complex that regulates the MAPK pathway activation (PubMed:35768504, PubMed:35831509, PubMed:36175670). The SMP complex specifically dephosphorylates the inhibitory phosphorylation at 'Ser-259' of RAF1 kinase, 'Ser-365' of BRAF kinase and 'Ser-214' of ARAF kinase, stimulating their kinase activities (PubMed:35768504, PubMed:35831509, PubMed:36175670). The SMP complex enhances the dephosphorylation activity and substrate specificity of PP1c (PubMed:35768504, PubMed:36175670).

Involvement in disease

Noonan syndrome-like disorder with loose anagen hair 2

NSLH2

A syndrome characterized by Noonan dysmorphic features such as macrocephaly, high forehead, hypertelorism, palpebral ptosis, low-set and posteriorly rotated ears, short and webbed neck, pectus anomalies, in association with pluckable, sparse, thin and slow-growing hair.

None

The disease is caused by variants affecting the gene represented in this entry.

Sequence Similarities

Belongs to the PPP phosphatase family. PP-1 subfamily.

Cellular localization

• Cytoplasm
• Nucleus
• Nucleus
• Nucleoplasm
• Nucleus
• Nucleolus
• Highly mobile in cells and can be relocalized through interaction with targeting subunits. In the presence of PPP1R8 relocalizes from the nucleus to nuclear speckles.

Alternative names

Serine/threonine-protein phosphatase PP1-beta catalytic subunit, PP-1B, PPP1CD, PPP1CB

Database links

swissprot:P62140 entrezGene:5500 entrezGene:5499 omim:176875 omim:600590 swissprot:P62136