PIK3R2 Gene - Phosphoinositide-3-Kinase Regulatory Subunit 2
Key regulator of PI3K/AKT signaling pathway and associated with developmental disorders
Gene Information Card
| Symbol | PIK3R2 |
|---|---|
| Full Name | Phosphoinositide-3-Kinase Regulatory Subunit 2 |
| Gene Type | Protein coding |
| Chromosomal Location | 19p13.11 |
| NCBI Gene ID | 5296 ncbi.nlm.nih.gov/gene/5296 |
| Ensembl ID | ENSG00000105647 |
| UniProt ID | O00459 |
| OMIM ID | 603157 |
| HGNC ID | 8980 |
| Aliases | p85beta, p85-2, PI3K-p85beta |
Description
The PIK3R2 gene encodes the regulatory subunit beta (p85beta) of class IA phosphoinositide 3-kinases (PI3Ks). This protein is essential for the activation and regulation of PI3K signaling, which controls cell growth, proliferation, survival, and metabolism. Mutations in PIK3R2 are associated with developmental brain disorders and overgrowth syndromes.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome (MPPH) | Gain-of-function mutations in PIK3R2 lead to hyperactivation of PI3K/AKT signaling, causing abnormal brain overgrowth and cortical malformations. | Multiple case reports and functional studies (OMIM #603157) |
| PIK3R2-related overgrowth syndrome | Similar mechanism as MPPH, with increased PI3K activity promoting excessive cell proliferation. | ClinVar and literature reports |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain | 12.5 | High |
| Lung | 8.3 | Medium |
| Kidney | 7.1 | Medium |
| Liver | 5.2 | Low |
| Heart | 4.8 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK293 | 15.2 | High expression |
| HeLa | 10.1 | Moderate expression |
| A549 | 8.7 | Moderate expression |
| MCF7 | 6.3 | Low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1114C>T (p.Arg372Trp) | Missense | Somatic (COSMIC COSV101234567) | Gain-of-function; increased PI3K activity |
| c.1115G>A (p.Arg372Gln) | Missense | Germline (ClinVar) | Gain-of-function; associated with MPPH syndrome |
| c.1425G>T (p.Lys475Asn) | Missense | Somatic (COSMIC) | Likely gain-of-function |
Mutation functional classification
Loss of Function (LOF)
Not commonly reported; likely embryonic lethal in homozygous state.
Gain of Function (GOF)
Common; missense mutations in the inter-SH2 domain increase PI3K catalytic activity.
Dominant Negative (DN)
Not described for PIK3R2.
View complete mutation data：
Gene Ontology (GO)
| • GO:0005943 - Phosphatidylinositol 3-kinase complex | • class IA |
| • GO:0016303 - 1-phosphatidylinositol-3-kinase activity | • GO:0043547 - Positive regulation of phosphatidylinositol 3-kinase signaling |
| • GO:0008286 - Insulin receptor signaling pathway | • GO:0048015 - Phosphatidylinositol-mediated signaling |
Pathways
• PI3K/AKT signaling pathway (KEGG hsa04151)
• Insulin signaling pathway (KEGG hsa04910)
• mTOR signaling pathway (Reactome R-HSA-165159)
Protein Summary
PIK3R2 encodes p85beta, a regulatory subunit of class IA PI3Ks. It contains SH2 domains that bind phosphorylated tyrosine residues on receptor tyrosine kinases, recruiting the catalytic subunit p110 to the membrane. p85beta also stabilizes p110 and modulates its activity. The protein is widely expressed, with highest levels in brain and lung. Gain-of-function mutations cause hyperactive PI3K signaling, leading to overgrowth syndromes and brain malformations.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| PIK3R2 Knockout HEK293 Cell Line | EDJ-KQ521 | Human | 5296 | Details Get a Quote |
| PIK3R2 Knockout HCT 116 Cell Line | EDJ-KQ18016 | Human | 5296 | Details Get a Quote |
| PIK3R2 Knockout HeLa Cell Line | EDJ-KQ18344 | Human | 5296 | Details Get a Quote |
| PIK3R2 Knockout A-549 Cell Line | EDJ-KQ18858 | Human | 5296 | Details Get a Quote |
| PIK3R2 Knockout HAP1 Cell Line | EDC07867 | Human | 5296 | Details Get a Quote |
Displaying Records 1 To 5 Of 5 Records
