Statements in which the resource exists as a subject.
PredicateObject
rdf:type
biopax3:comment
FUNCTION: Phosphoinositide-3-kinase (PI3K) that phosphorylates PtdIns (Phosphatidylinositol), PtdIns4P (Phosphatidylinositol 4- phosphate) and PtdIns(4,5)P2 (Phosphatidylinositol 4,5- bisphosphate) to generate phosphatidylinositol 3,4,5-trisphosphate (PIP3). PIP3 plays a key role by recruiting PH domain-containing proteins to the membrane, including AKT1 and PDPK1, activating signaling cascades involved in cell growth, survival, proliferation, motility and morphology. Participates in cellular signaling in response to various growth factors. Involved in the activation of AKT1 upon stimulation by receptor tyrosine kinases ligands such as EGF, insulin, IGF1, VEGFA and PDGF. Involved in signaling via insulin-receptor substrate (IRS) proteins. Essential in endothelial cell migration during vascular development through VEGFA signaling, possibly by regulating RhoA activity. Required for lymphatic vasculature development, possibly by binding to RAS and by activation by EGF and FGF2, but not by PDGF. Regulates invadopodia formation in breast cancer cells through the PDPK1- AKT1 pathway. Participates in cardiomyogenesis in embryonic stem cells through a AKT1 pathway. Participates in vasculogenesis in embryonic stem cells through PDK1 and protein kinase C pathway. Has also serine-protein kinase activity: phosphorylates PIK3R1 (p85alpha regulatory subunit), EIF4EBP1 and HRAS. CATALYTIC ACTIVITY: ATP + 1-phosphatidyl-1D-myo-inositol 4,5- bisphosphate = ADP + 1-phosphatidyl-1D-myo-inositol 3,4,5- trisphosphate. CATALYTIC ACTIVITY: ATP + a protein = ADP + a phosphoprotein. SUBUNIT: Heterodimer of a catalytic subunit PIK3CA and a p85 regulatory subunit (PIK3R1, PIK3R2 or PIK3R3). Interacts with IRS1 in nuclear extracts. Interacts with RUFY3 (By similarity). Interacts with RASD2 (By similarity). Interacts with APPL1. Interacts with HRAS1 and KRAS (By similarity). Interaction with HRAS1/KRAS is required for PI3K pathway signaling and cell proliferation stimulated by EGF and FGF2 (By similarity). DOMAIN: The PI3K-ABD domain and the PI3K-RBD domain interact with the PI3K/PI4K kinase domain. The C2 PI3K-type domain may facilitate the recruitment to the plasma membrane. The inhibitory interactions with PIK3R1 are mediated by the PI3K-ABD domain and the C2 PI3K-type domain with the iSH2 (inter-SH2) region of PIK3R1, and the C2 PI3K-type domain, the PI3K helical domain, and the PI3K/PI4K kinase domain with the nSH2 (N-terminal SH2) region of PIK3R1. DISEASE: Note=Most of the cancer-derived mutations are missense mutations and map to one of the three hotspots: Glu-542; Glu-545 and His-1047. Mutated isoforms participate in cellular transformation and tumorigenesis induced by oncogenic receptor tyrosine kinases (RTKs) and HRAS1/KRAS. Interaction with HRAS1/KRAS is required for Ras-driven tumor formation. Mutations increasing the lipid kinase activity are required for oncogenic signaling. The protein kinase activity may not be required for tumorigenesis. DISEASE: Defects in PIK3CA are associated with colorectal cancer (CRC) [MIM:114500]. DISEASE: Defects in PIK3CA are a cause of susceptibility to breast cancer (BC) [MIM:114480]. A common malignancy originating from breast epithelial tissue. Breast neoplasms can be distinguished by their histologic pattern. Invasive ductal carcinoma is by far the most common type. Breast cancer is etiologically and genetically heterogeneous. Important genetic factors have been indicated by familial occurrence and bilateral involvement. Mutations at more than one locus can be involved in different families or even in the same case. DISEASE: Defects in PIK3CA are a cause of susceptibility to ovarian cancer (OC) [MIM:167000]. Ovarian cancer common malignancy originating from ovarian tissue. Although many histologic types of ovarian neoplasms have been described, epithelial ovarian carcinoma is the most common form. Ovarian cancers are often asymptomatic and the recognized signs and symptoms, even of late- stage disease, are vague. Consequently, most patients are diagnosed with advanced disease. DISEASE: Defects in PIK3CA may underlie hepatocellular carcinoma (HCC) [MIM:114550]. DISEASE: Defects in PIK3CA are a cause of keratosis seborrheic (KERSEB) [MIM:182000]. A common benign skin tumor. Seborrheic keratoses usually begin with the appearance of one or more sharply defined, light brown, flat macules. The lesions may be sparse or numerous. As they initially grow, they develop a velvety to finely verrucous surface, followed by an uneven warty surface with multiple plugged follicles and a dull or lackluster appearance. MISCELLANEOUS: The avian sarcoma virus 16 genome encodes an oncogene derived from PIK3CA (PubMed:18418043). SIMILARITY: Belongs to the PI3/PI4-kinase family. SIMILARITY: Contains 1 C2 PI3K-type domain. SIMILARITY: Contains 1 PI3K-ABD domain. SIMILARITY: Contains 1 PI3K-RBD domain. SIMILARITY: Contains 1 PI3K/PI4K domain. SIMILARITY: Contains 1 PIK helical domain. GENE SYNONYMS:PIK3CA. COPYRIGHT: Protein annotation is derived from the UniProt Consortium (http://www.uniprot.org/). Distributed under the Creative Commons Attribution-NoDerivs License., SEQUENCE 1068 AA; 124284 MW; 041487231A9A1207 CRC64;
biopax3:xref
biopax3:displayName
PK3CA_HUMAN
biopax3:name
2.7.1.153, 2.7.11.1, PI3-kinase subunit alpha, PI3K-alpha, PI3Kalpha, PIK3CA, Phosphatidylinositol 4,5-bisphosphate 3-kinase 110 kDa catalytic subunit alpha, Phosphoinositide-3-kinase catalytic alpha polypeptide, PtdIns-3-kinase subunit alpha, PtdIns-3-kinase subunit p110-alpha, Serine/threonine protein kinase PIK3CA, p110alpha
biopax3:organism
biopax3:sequence
MPPRPSSGELWGIHLMPPRILVECLLPNGMIVTLECLREATLITIKHELFKEARKYPLHQLLQDESSYIFVSVTQEAEREEFFDETRRLCDLRLFQPFLKVIEPVGNREEKILNREIGFAIGMPVCEFDMVKDPEVQDFRRNILNVCKEAVDLRDLNSPHSRAMYVYPPNVESSPELPKHIYNKLDKGQIIVVIWVIVSPNNDKQKYTLKINHDCVPEQVIAEAIRKKTRSMLLSSEQLKLCVLEYQGKYILKVCGCDEYFLEKYPLSQYKYIRSCIMLGRMPNLMLMAKESLYSQLPMDCFTMPSYSRRISTATPYMNGETSTKSLWVINSALRIKILCATYVNVNIRDIDKIYVRTGIYHGGEPLCDNVNTQRVPCSNPRWNEWLNYDIYIPDLPRAARLCLSICSVKGRKGAKEEHCPLAWGNINLFDYTDTLVSGKMALNLWPVPHGLEDLLNPIGVTGSNPNKETPCLELEFDWFSSVVKFPDMSVIEEHANWSVSREAGFSYSHAGLSNRLARDNELRENDKEQLKAISTRDPLSEITEQEKDFLWSHRHYCVTIPEILPKLLLSVKWNSRDEVAQMYCLVKDWPPIKPEQAMELLDCNYPDPMVRGFAVRCLEKYLTDDKLSQYLIQLVQVLKYEQYLDNLLVRFLLKKALTNQRIGHFFFWHLKSEMHNKTVSQRFGLLLESYCRACGMYLKHLNRQVEAMEKLINLTDILKQEKKDETQKVQMKFLVEQMRRPDFMDALQGFLSPLNPAHQLGNLRLEECRIMSSAKRPLWLNWENPDIMSELLFQNNEIIFKNGDDLRQDMLTLQIIRIMENIWQNQGLDLRMLPYGCLSIGDCVGLIEVVRNSHTIMQIQCKGGLKGALQFNSHTLHQWLKDKNKGEIYDAAIDLFTRSCAGYCVATFILGIGDRHNSNIMVKDDGQLFHIDFGHFLDHKKKKFGYKRERVPFVLTQDFLIVISKGAQECTKTREFERFQEMCYKAYLAIRQHANLFINLFSMMLGSGMPELQSFDDIAYIRKTLALDKTEQEALEYFMKQMNDAHHGGWTTKMDWIFHTIKQHALN
biopax3:standardName
Phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit alpha isoform