P110α

Phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha
PI3 Kinase 110 alpha bound to the inhibitor PIK-93 (yellow).
Available structures PDB Ortholog search: PDBe, RCSB List of PDB id codes 2ENQ, 2RD0, 3HHM, 3HIZ, 3ZIM, 4JPS, 4L1B, 4L23, 4L2Y, 4OVU, 4OVV, 4TUU, 4TV3, 4WAF
Identifiers
Symbols	PIK3CA ; CLOVE; CWS5; MCAP; MCM; MCMTC; PI3K; p110-alpha
External IDs	OMIM: 171834 MGI: 1206581 HomoloGene: 21249 IUPHAR: 2153 ChEMBL: 4005 GeneCards: PIK3CA Gene
EC number	2.7.1.153, 2.7.11.1
Gene ontology Molecular function • protein serine/threonine kinase activity • protein binding • ATP binding • kinase activity • 1-phosphatidylinositol-3-kinase activity • protein kinase activator activity • phosphatidylinositol 3-kinase activity • 1-phosphatidylinositol-4-phosphate 3-kinase activity • insulin receptor substrate binding • phosphatidylinositol-4,5-bisphosphate 3-kinase activity Cellular component • cytoplasm • cytosol • plasma membrane • phosphatidylinositol 3-kinase complex • phosphatidylinositol 3-kinase complex, class IA • lamellipodium Biological process • angiogenesis • liver development • vasculature development • adaptive immune response • glucose metabolic process • protein phosphorylation • phospholipid metabolic process • phosphatidylinositol biosynthetic process • inflammatory response • epidermal growth factor receptor signaling pathway • blood coagulation • insulin receptor signaling pathway • fibroblast growth factor receptor signaling pathway • phosphatidylinositol 3-kinase signaling • platelet activation • T cell costimulation • activation of protein kinase activity • positive regulation of peptidyl-serine phosphorylation • phosphatidylinositol-3-phosphate biosynthetic process • insulin receptor signaling pathway via phosphatidylinositol 3-kinase • Fc-epsilon receptor signaling pathway • Fc-gamma receptor signaling pathway involved in phagocytosis • regulation of multicellular organism growth • regulation of cellular respiration • protein kinase B signaling • negative regulation of neuron apoptotic process • endothelial cell migration • hypomethylation of CpG island • small molecule metabolic process • innate immune response • phosphatidylinositol phosphorylation • vascular endothelial growth factor receptor signaling pathway • neurotrophin TRK receptor signaling pathway • phosphatidylinositol-mediated signaling • T cell receptor signaling pathway • leukocyte migration • cardiac muscle contraction • cell chemotaxis • adipose tissue development • cellular response to glucose stimulus • energy homeostasis • activation of mitophagy in response to mitochondrial depolarization • negative regulation of fibroblast apoptotic process • regulation of genetic imprinting • negative regulation of anoikis Sources: Amigo / QuickGO
RNA expression pattern
File:PBB GE PIK3CA 204369 at tn.png
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	5290	18706
Ensembl	ENSG00000121879	ENSMUSG00000027665
UniProt	P42336	P42337
RefSeq (mRNA)	NM_006218	NM_008839
RefSeq (protein)	NP_006209	NP_032865
Location (UCSC)	Chr 3: 179.15 – 179.24 Mb	Chr 3: 32.4 – 32.47 Mb
PubMed search	[1]	[2]

The phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (the HUGO-approved official symbol = PIK3CA; HGNC ID, HGNC:8975), also called p110α protein, is a class I PI 3-kinase catalytic subunit. The human p110α protein is encoded by the PIK3CA gene.

Function

Phosphatidylinositol-4,5-bisphosphate 3-kinase (also called phosphatidylinositol 3-kinase) is composed of an 85 kDa regulatory subunit and a 110 kDa catalytic subunit. The protein encoded by this gene represents the catalytic subunit, which uses ATP to phosphorylate phosphatidylinositols (PtdIns), PtdIns4P and PtdIns(4,5)P2.

Clinical significance

Recent evidence has shown that the PIK3CA gene is mutated in a range of human cancers. It has been found to be oncogenic and has been implicated in cervical cancers.

Due to the association between p110α and cancer, it is believed to be a promising drug target. A number of pharmaceutical companies are currently designing and charactering potential p110α isoform specific inhibitors. The presence of PIK3CA mutation may predict response to aspirin therapy for colorectal cancer, indicating power and promise of "Molecular Pathological Epidemiology (MPE)" approach as well as a complex interaction within the tumor microenvironment in this phenomenon.

Somatic mosaic mutations in PIK3CA have been implicated in several overgrowth conditions: CLOVES syndrome, macrocephaly-capillary malformation syndrome, hemimegalencephaly and overgrowth with fibroadipose hyperplasia. Somatic activating mutations in PIK3CA also cause vascular malformation in lymphatics and veins and and are found in Klippel-Trenaunay syndrome.

See also

• Phosphoinositide 3-kinase

Interactions

P110α has been shown to interact with:

• ARHGEF1,
• ADAP1,
• DGKZ,
• HRAS, and
• Lck.