Reactome: A Curated Pathway Database
THIS SITE IS USED FOR CURATION AND TESTING
IT IS NOT STABLE, IS LINKED TO AN INCOMPLETE DATA SET, AND IS NOT MONITORED FOR PERFORMANCE. WE STRONGLY RECOMMEND THE USE OF OUR PUBLIC SITE

Query author contributions in Reactome

Reactome depends on collaboration between our curation team and outside experts to assemble and peer-review its pathway modules. The integration of ORCID within Reactome enables us to meet a key challenge with authoring, curating and reviewing biological information by incentivizing and crediting the external experts that contribute their expertise and time to the Reactome curation process. More information is available at ORCID and Reactome.

If you have an ORCID ID that is not listed on this page, please forward this information to us and we will update your Reactome pathway records.

Name Email address

Details on Person UniProt:Q8BTI9 Pik3cb

Class:IdReferenceGeneProduct:242957
_chainChangeLogchain:1-1064 added on Fri February 6 2015
_displayNameUniProt:Q8BTI9 Pik3cb
_timestamp2025-05-21 21:38:38
chainchain:1-1064
checksumEBDF0266BF0A2032
commentFUNCTION Phosphoinositide-3-kinase (PI3K) phosphorylates phosphatidylinositol (PI) derivatives at position 3 of the inositol ring to produce 3-phosphoinositides. Uses ATP and PtdIns(4,5)P2 (phosphatidylinositol 4,5-bisphosphate) to generate phosphatidylinositol 3,4,5-trisphosphate (PIP3) (By similarity). 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. Involved in the activation of AKT1 upon stimulation by G-protein coupled receptors (GPCRs) ligands such as CXCL12, sphingosine 1-phosphate, and lysophosphatidic acid. May also act downstream receptor tyrosine kinases. Required in different signaling pathways for stable platelet adhesion and aggregation. Plays a role in platelet activation signaling triggered by GPCRs, alpha-IIb/beta-3 integrins (ITGA2B/ ITGB3) and ITAM (immunoreceptor tyrosine-based activation motif)-bearing receptors such as GP6. Regulates the strength of adhesion of ITGA2B/ ITGB3 activated receptors necessary for the cellular transmission of contractile forces. Required for platelet aggregation induced by F2 (thrombin) and thromboxane A2 (TXA2). Has a role in cell survival. May have a role in cell migration. Involved in the early stage of autophagosome formation. Modulates the intracellular level of PtdIns3P (phosphatidylinositol 3-phosphate) and activates PIK3C3 kinase activity. May act as a scaffold, independently of its lipid kinase activity to positively regulate autophagy. May have a role in insulin signaling as scaffolding protein in which the lipid kinase activity is not required. May have a kinase-independent function in regulating cell proliferation and in clathrin-mediated endocytosis. Mediator of oncogenic signal in cell lines lacking PTEN. The lipid kinase activity is necessary for its role in oncogenic transformation. Required for the growth of ERBB2 and RAS driven tumors. Also has a protein kinase activity showing autophosphorylation.CATALYTIC ACTIVITY a 1,2-diacyl-sn-glycero-3-phospho-(1D-myo-inositol-4,5-bisphosphate) + ATP = a 1,2-diacyl-sn-glycero-3-phospho-(1D-myo-inositol-3,4,5-trisphosphate) + ADP + H(+)CATALYTIC ACTIVITY 1-octadecanoyl-2-(5Z,8Z,11Z,14Z)-eicosatetraenoyl-sn-glycero-3-phospho-1D-myo-inositol 4,5-bisphosphate + ATP = 1-octadecanoyl-2-(5Z,8Z,11Z,14Z-eicosatetraenoyl)-sn-glycero-3-phospho-(1D-myo-inositol 3,4,5-triphosphate) + ADP + H(+)CATALYTIC ACTIVITY L-seryl-[protein] + ATP = O-phospho-L-seryl-[protein] + ADP + H(+)PATHWAY Phospholipid metabolism; phosphatidylinositol phosphate biosynthesis.SUBUNIT Heterodimer of a catalytic subunit PIK3CB and a p85 regulatory subunit (PIK3R1, PIK3R2 or PIK3R3). Interaction with PIK3R2 is required for nuclear localization and nuclear export (By similarity). Part of a complex with PIK3R1 and PTEN (By similarity). Binding to PTEN may antagonize the lipid kinase activity under normal growth conditions (By similarity). Part of a complex involved in autophagosome formation composed of PIK3C3 and PIK3R4. Interacts with BECN1, ATG14 and RAB5A.INTERACTION Interaction with PIK3R2 is required for nuclear localization and export.DOMAIN 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; the C2 PI3K-type domain, the PI3K helical domain, and the PI3K/PI4K kinase domain with the nSH2 (N-terminal SH2) region of PIK3R1; and the PI3K/PI4K kinase domain with the cSH2 (C-terminal SH2) region of PIK3R1. The inhibitory interaction between the PI3K-ABD domain and the C2 PI3K-type domain with the iSH2 (inter-SH2) region of PIK3R1 is weak. The nuclear localization signal (NLS) is required for its function in cell survival (By similarity).PTM Phosphorylation at Ser-1064 down-regulates lipid kinase activity.PTM Autophosphorylation at Ser-1064 negatively regulates the phosphatidylinositol-4,5-bisphosphate 3-kinase activity.DISRUPTION PHENOTYPE Mice have defects in autophagosome formation. Have normal bleeding time but are resistant to thrombosis after arterial injury. Mice fail to induce tumors in a model of prostate tumor formation induced by Pten loss.SIMILARITY Belongs to the PI3/PI4-kinase family.
created[InstanceEdit:217385] Schmidt, EE, 2008-03-27 06:23:53
descriptionrecommendedName: Phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit beta isoform shortName: PI3-kinase subunit beta shortName: PI3K-beta shortName: PI3Kbeta shortName: PtdIns-3-kinase subunit beta ecNumber evidence="2"2.7.1.153 alternativeName: Phosphatidylinositol 4,5-bisphosphate 3-kinase 110 kDa catalytic subunit beta shortName: PtdIns-3-kinase subunit p110-beta shortName: p110beta alternativeName: fullName evidence="2"Serine/threonine protein kinase PIK3CB ecNumber evidence="2"2.7.11.1
geneNamePik3cb
identifierQ8BTI9
isSequenceChangedFALSE
keyword3D-structure
ATP-binding
Autophagy
Cell adhesion
Cytoplasm
Endocytosis
Kinase
Lipid metabolism
Nucleotide-binding
Nucleus
Phosphoprotein
Reference proteome
Transferase
modified[InstanceEdit:354386] Schmidt, EE, 2008-06-18 04:45:12
[InstanceEdit:384350] Kanapin, AA, 2008-11-26 14:00:39
[InstanceEdit:392885] Kanapin, AA, 2009-03-09 12:07:18
[InstanceEdit:400710] Schmidt, EE, 2009-03-25 05:33:35
[InstanceEdit:423310] Kanapin, AA
[InstanceEdit:435478] Kanapin, AA
[InstanceEdit:435871] Kanapin, AA
[InstanceEdit:447347] Kanapin, AA
[InstanceEdit:525883] Kanapin, AA
[InstanceEdit:613449] Kanapin, AA
[InstanceEdit:797602] Kanapin, AA
[InstanceEdit:937368] Yung, CK
[InstanceEdit:1042053] Yung, CK
[InstanceEdit:1220657] Yung, CK
[InstanceEdit:1300696] Yung, CK
[InstanceEdit:1301627] Yung, CK
[InstanceEdit:1551960] Weiser, JD
[InstanceEdit:1995863] Weiser, JD
[InstanceEdit:2132304] Weiser, JD
[InstanceEdit:2265580] Weiser, JD
[InstanceEdit:5433710] Weiser, JD
[InstanceEdit:5618415] Weiser, JD
[InstanceEdit:5634237] Weiser, JD
[InstanceEdit:5673015] Weiser, JD
[InstanceEdit:9037114] Weiser, JD
[InstanceEdit:9637257] Weiser, JD
[InstanceEdit:9657908] Weiser, JD
[InstanceEdit:9676415] Weiser, JD
[InstanceEdit:9715482] Weiser, JD
[InstanceEdit:9730071] Weiser, JD
[InstanceEdit:9767224] Weiser, Joel
[InstanceEdit:9796772] Weiser, Joel
[InstanceEdit:9852000] Weiser, Joel, 2023-11-03
[InstanceEdit:9939033] Weiser, Joel, 2025-02-21
[InstanceEdit:9948485] Weiser, Joel, 2025-05-21
namePik3cb
referenceDatabase[ReferenceDatabase:2] UniProt
secondaryIdentifierPK3CB_MOUSE
Q3U4Q1
sequenceLength1064
species[Species:48892] Mus musculus
(referenceEntity)[EntityWithAccessionedSequence:9027217] Pik3cb [cytosol] [Mus musculus]
[Change default viewing format]
No pathways have been reviewed or authored by UniProt:Q8BTI9 Pik3cb (242957)