PPP1CB (Protein Phosphatase 1 Catalytic Subunit Beta): Gene, Function, and Disease Associations
A comprehensive overview of the PPP1CB gene, including its genomic context, protein function, expression patterns, and clinical significance.
Gene Information Card
| Symbol | PPP1CB |
|---|---|
| Full Name | Protein Phosphatase 1 Catalytic Subunit Beta |
| Gene Type | Protein coding |
| Chromosomal Location | 2p23.2 |
| NCBI Gene ID | 5500 ncbi.nlm.nih.gov/gene/5500 |
| Ensembl ID | ENSG00000213639 |
| UniProt ID | P62140 |
| OMIM ID | 600590 |
| HGNC ID | 9282 |
| Aliases | PP-1B, PP1B, PPP1CD |
Description
The PPP1CB gene encodes the beta isoform of the catalytic subunit of protein phosphatase 1 (PP1), a serine/threonine phosphatase that regulates diverse cellular processes including glycogen metabolism, cell cycle progression, muscle contraction, and neuronal signaling. PP1 holoenzymes consist of a catalytic subunit (PPP1CA, PPP1CB, or PPP1CC) and a regulatory subunit that determines substrate specificity and subcellular localization. PPP1CB is ubiquitously expressed and plays a critical role in development, as mutations in this gene cause Noonan syndrome-like disorder with loose anagen hair (NSLH) and other RASopathies.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Noonan syndrome-like disorder with loose anagen hair (NSLH) | Heterozygous missense mutations in PPP1CB lead to altered PP1 activity, dysregulating the RAS-MAPK signaling pathway, which is critical for development. | ClinVar, OMIM |
| Noonan syndrome | PPP1CB mutations are associated with a Noonan syndrome phenotype, likely through similar disruption of RAS-MAPK signaling. | ClinVar, OMIM |
| Intellectual disability | PPP1CB mutations may contribute to neurodevelopmental phenotypes, possibly via impaired synaptic plasticity and neuronal signaling. | ClinVar |
| Cardiac defects | PPP1CB mutations are associated with congenital heart defects, possibly due to disrupted PP1 function in cardiac development. | ClinVar |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain | 17.4 | Medium |
| Heart | 14.2 | Medium |
| Liver | 12.8 | Medium |
| Kidney | 11.5 | Medium |
| Testis | 10.9 | Medium |
| Lung | 9.8 | Low |
| Spleen | 8.7 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HeLa | 15.3 | High expression |
| A549 | 12.1 | Moderate expression |
| HepG2 | 11.8 | Moderate expression |
| K562 | 10.5 | Moderate expression |
| MCF7 | 9.9 | Low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| p.Asp197Tyr (c.589G>T) | Missense | Rare | Likely gain-of-function; associated with Noonan syndrome-like phenotype. |
| p.Phe201Leu (c.601T>C) | Missense | Rare | Likely gain-of-function; associated with Noonan syndrome. |
| p.Arg265Gln (c.794G>A) | Missense | Rare | Uncertain; reported in ClinVar as likely pathogenic. |
| p.Gly274Asp (c.821G>A) | Missense | Rare | Likely gain-of-function; associated with NSLH. |
Mutation functional classification
Loss of Function (LOF)
Loss-of-function mutations in PPP1CB are rare and not well characterized; complete loss may be lethal due to essential PP1 function.
Gain of Function (GOF)
Most pathogenic PPP1CB mutations are missense and are considered gain-of-function, leading to increased PP1 activity that disrupts RAS-MAPK signaling.
Dominant Negative (DN)
Some mutations may act in a dominant-negative manner, interfering with holoenzyme formation and reducing overall PP1 activity, though evidence is limited.
View complete mutation data：
Gene Ontology (GO)
| • protein serine/threonine phosphatase activity | • phosphoprotein phosphatase activity |
| • metal ion binding | • protein binding |
| • signal transduction | • dephosphorylation |
| • cell cycle | • glycogen metabolic process |
| • regulation of transcription | • DNA-templated |
Pathways
• RAS/MAPK signaling pathway
• Glycogen metabolism
• Cell cycle regulation
• Wnt signaling pathway
• TGF-beta signaling pathway
Protein Summary
The PPP1CB protein is a 327-amino acid catalytic subunit of protein phosphatase 1. It is highly conserved and ubiquitously expressed. PP1 catalytic subunits form holoenzymes with various regulatory subunits, targeting them to specific substrates. PPP1CB is involved in dephosphorylating key proteins in glycogen metabolism (e.g., glycogen phosphorylase), muscle contraction (myosin light chain), and cell cycle (retinoblastoma protein). Mutations in PPP1CB are associated with RASopathies, particularly Noonan syndrome-like disorder with loose anagen hair, highlighting its role in development and signaling.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| PPP1CB Knockout HEK293 Cell Line | EDJ-KQ50532 | Human | 5500 | Details Get a Quote |
| PPP1CB Knockout HeLa Cell Line | EDJ-KQ54191 | Human | 5500 | Details Get a Quote |
| PPP1CB Knockout A-549 Cell Line | EDJ-KQ62685 | Human | 5500 | Details Get a Quote |
| PPP1CB Knockout HCT 116 Cell Line | EDJ-KQ71154 | Human | 5500 | Details Get a Quote |
