lmmol · Proteins

Phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit delta isoform

UniProt O00329 Organism Homo sapiens Gene PIK3CD EC 2.7.1.137, 2.7.1.153

Also known as: PIK3CD

Function

Phosphoinositide-3-kinase (PI3K) phosphorylates phosphatidylinositol (PI) and its phosphorylated 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). 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. Mediates immune responses. Plays a role in B-cell development, proliferation, migration, and function. Required for B-cell receptor (BCR) signaling. Mediates B-cell proliferation response to anti-IgM, anti-CD40 and IL4 stimulation. Promotes cytokine production in response to TLR4 and TLR9. Required for antibody class switch mediated by TLR9. Involved in the antigen presentation function of B-cells. Involved in B-cell chemotaxis in response to CXCL13 and sphingosine 1-phosphate (S1P). Required for proliferation, signaling and cytokine production of naive, effector and memory T-cells. Required for T-cell receptor (TCR) signaling. Mediates TCR signaling events at the immune synapse. Activation by TCR leads to antigen-dependent memory T-cell migration and retention to antigenic tissues. Together with PIK3CG participates in T-cell development. Contributes to T-helper cell expansion and differentiation. Required for T-cell migration mediated by homing receptors SELL/CD62L, CCR7 and S1PR1 and antigen dependent recruitment of T-cells. Together with PIK3CG is involved in natural killer (NK) cell development and migration towards the sites of inflammation. Participates in NK cell receptor activation. Plays a role in NK cell maturation and cytokine production. Together with PIK3CG is involved in neutrophil chemotaxis and extravasation. Together with PIK3CG participates in neutrophil respiratory burst. Plays important roles in mast-cell development and mast cell mediated allergic response. Involved in stem cell factor (SCF)-mediated proliferation, adhesion and migration. Required for allergen-IgE-induced degranulation and cytokine release. The lipid kinase activity is required for its biological function. Isoform 2 may be involved in stabilizing total RAS levels, resulting in increased ERK phosphorylation and increased PI3K activity.

Classification

Family (Pfam)
PF00454 PI3_PI4_kinase, PF00792 PI3K_C2, PF02192 PI3K_p85B, PF00794 PI3K_rbd, PF00613 PI3Ka
InterPro
ARM-type_fold, C2_domain_sf, Kinase-like_dom_sf, PI3-kinase_delta_cat, PI3/4_kinase, PI3/4_kinase_cat_dom, PI3/4_kinase_cat_sf, PI3/4_kinase_CS, PI3K-type_C2_dom, PI3K_ABD, PI3K_accessory_dom, PI3K_accessory_sf, PI3K_Ras-bd_dom, Ubiquitin-like_domsf
Functional cluster
Eukaryotic Transcription Factors & related

Experimental structures · PDB · 18

A predicted model is available from AlphaFold.

Gene Ontology · 46

Disease associations

Drugs targeting this protein · 41

Related proteins · sequence + function similarity

Co-cited proteins · studied together in the literature

Literature · 17 cited papers

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