ID A0A3Q2H9K0_HORSE Unreviewed; 981 AA.
AC A0A3Q2H9K0;
DT 10-APR-2019, integrated into UniProtKB/TrEMBL.
DT 13-SEP-2023, sequence version 2.
DT 18-JUN-2025, entry version 31.
DE RecName: Full=Phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit beta isoform {ECO:0000256|ARBA:ARBA00068828};
DE EC=2.7.1.153 {ECO:0000256|ARBA:ARBA00012010};
DE EC=2.7.11.1 {ECO:0000256|ARBA:ARBA00012513};
DE AltName: Full=Phosphatidylinositol 4,5-bisphosphate 3-kinase 110 kDa catalytic subunit beta {ECO:0000256|ARBA:ARBA00080896};
DE AltName: Full=Serine/threonine protein kinase PIK3CB {ECO:0000256|ARBA:ARBA00076131};
GN Name=PIK3CB {ECO:0000313|Ensembl:ENSECAP00000029922.2,
GN ECO:0000313|VGNC:VGNC:21447};
OS Equus caballus (Horse).
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC Eutheria; Laurasiatheria; Perissodactyla; Equidae; Equus.
OX NCBI_TaxID=9796 {ECO:0000313|Ensembl:ENSECAP00000029922.2, ECO:0000313|Proteomes:UP000002281};
RN [1] {ECO:0000313|Ensembl:ENSECAP00000029922.2, ECO:0000313|Proteomes:UP000002281}
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=Thoroughbred {ECO:0000313|Ensembl:ENSECAP00000029922.2,
RC ECO:0000313|Proteomes:UP000002281};
RX PubMed=19892987; DOI=10.1126/science.1178158;
RG Broad Institute Genome Sequencing Platform;
RG Broad Institute Whole Genome Assembly Team;
RA Wade C.M., Giulotto E., Sigurdsson S., Zoli M., Gnerre S., Imsland F.,
RA Lear T.L., Adelson D.L., Bailey E., Bellone R.R., Bloecker H., Distl O.,
RA Edgar R.C., Garber M., Leeb T., Mauceli E., MacLeod J.N., Penedo M.C.T.,
RA Raison J.M., Sharpe T., Vogel J., Andersson L., Antczak D.F., Biagi T.,
RA Binns M.M., Chowdhary B.P., Coleman S.J., Della Valle G., Fryc S.,
RA Guerin G., Hasegawa T., Hill E.W., Jurka J., Kiialainen A., Lindgren G.,
RA Liu J., Magnani E., Mickelson J.R., Murray J., Nergadze S.G., Onofrio R.,
RA Pedroni S., Piras M.F., Raudsepp T., Rocchi M., Roeed K.H., Ryder O.A.,
RA Searle S., Skow L., Swinburne J.E., Syvaenen A.C., Tozaki T., Valberg S.J.,
RA Vaudin M., White J.R., Zody M.C., Lander E.S., Lindblad-Toh K.;
RT "Genome sequence, comparative analysis, and population genetics of the
RT domestic horse.";
RL Science 326:865-867(2009).
RN [2] {ECO:0000313|Ensembl:ENSECAP00000029922.2}
RP IDENTIFICATION.
RC STRAIN=Thoroughbred {ECO:0000313|Ensembl:ENSECAP00000029922.2};
RG Ensembl;
RL Submitted (MAR-2025) to UniProtKB.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=1-octadecanoyl-2-(5Z,8Z,11Z,14Z)-eicosatetraenoyl-sn-glycero-
CC 3-phospho-1D-myo-inositol 4,5-bisphosphate + ATP = 1-octadecanoyl-2-
CC (5Z,8Z,11Z,14Z-eicosatetraenoyl)-sn-glycero-3-phospho-(1D-myo-
CC inositol 3,4,5-triphosphate) + ADP + H(+); Xref=Rhea:RHEA:43396,
CC ChEBI:CHEBI:15378, ChEBI:CHEBI:30616, ChEBI:CHEBI:77137,
CC ChEBI:CHEBI:83243, ChEBI:CHEBI:456216;
CC Evidence={ECO:0000256|ARBA:ARBA00051347};
CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:43397;
CC Evidence={ECO:0000256|ARBA:ARBA00051347};
CC -!- CATALYTIC ACTIVITY:
CC Reaction=L-seryl-[protein] + ATP = O-phospho-L-seryl-[protein] + ADP +
CC H(+); Xref=Rhea:RHEA:17989, Rhea:RHEA-COMP:9863, Rhea:RHEA-
CC COMP:11604, ChEBI:CHEBI:15378, ChEBI:CHEBI:29999, ChEBI:CHEBI:30616,
CC ChEBI:CHEBI:83421, ChEBI:CHEBI:456216; EC=2.7.11.1;
CC Evidence={ECO:0000256|ARBA:ARBA00048977};
CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:17990;
CC Evidence={ECO:0000256|ARBA:ARBA00048977};
CC -!- CATALYTIC ACTIVITY:
CC Reaction=a 1,2-diacyl-sn-glycero-3-phospho-(1D-myo-inositol-4,5-
CC bisphosphate) + ATP = a 1,2-diacyl-sn-glycero-3-phospho-(1D-myo-
CC inositol-3,4,5-trisphosphate) + ADP + H(+); Xref=Rhea:RHEA:21292,
CC ChEBI:CHEBI:15378, ChEBI:CHEBI:30616, ChEBI:CHEBI:57836,
CC ChEBI:CHEBI:58456, ChEBI:CHEBI:456216; EC=2.7.1.153;
CC Evidence={ECO:0000256|ARBA:ARBA00023981};
CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:21293;
CC Evidence={ECO:0000256|ARBA:ARBA00023981};
CC -!- PATHWAY: Lipid metabolism. {ECO:0000256|ARBA:ARBA00005189}.
CC -!- PATHWAY: Phospholipid metabolism; phosphatidylinositol phosphate
CC biosynthesis. {ECO:0000256|ARBA:ARBA00004805}.
CC -!- SUBUNIT: Heterodimer of a catalytic subunit PIK3CB and a p85 regulatory
CC subunit (PIK3R1, PIK3R2 or PIK3R3). Interaction with PIK3R2 is required
CC for nuclear localization and nuclear export. Part of a complex with
CC PIK3R1 and PTEN. Binding to PTEN may antagonize the lipid kinase
CC activity under normal growth conditions. Part of a complex involved in
CC autophagosome formation composed of PIK3C3 and PIK3R4. Interacts with
CC BECN1, ATG14 and RAB5A. {ECO:0000256|ARBA:ARBA00065016}.
CC -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000256|ARBA:ARBA00004496}.
CC Nucleus {ECO:0000256|ARBA:ARBA00004123}.
CC -!- SIMILARITY: Belongs to the PI3/PI4-kinase family. Type III PI4K
CC subfamily. {ECO:0000256|ARBA:ARBA00006209}.
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DR AlphaFoldDB; A0A3Q2H9K0; -.
DR Ensembl; ENSECAT00000060585.2; ENSECAP00000029922.2; ENSECAG00000023941.4.
DR VGNC; VGNC:21447; PIK3CB.
DR GeneTree; ENSGT00940000157522; -.
DR UniPathway; UPA00220; -.
DR Proteomes; UP000002281; Chromosome 16.
DR Bgee; ENSECAG00000023941; Expressed in inner cell mass and 23 other cell types or tissues.
DR ExpressionAtlas; A0A3Q2H9K0; baseline.
DR GO; GO:0005737; C:cytoplasm; IEA:UniProtKB-ARBA.
DR GO; GO:0046934; F:1-phosphatidylinositol-4,5-bisphosphate 3-kinase activity; IEA:UniProtKB-EC.
DR GO; GO:0005524; F:ATP binding; IEA:UniProtKB-KW.
DR GO; GO:0046854; P:phosphatidylinositol phosphate biosynthetic process; IEA:InterPro.
DR CDD; cd08693; C2_PI3K_class_I_beta_delta; 1.
DR CDD; cd00872; PI3Ka_I; 1.
DR FunFam; 1.10.1070.11:FF:000001; Phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit; 1.
DR FunFam; 2.60.40.150:FF:000046; Phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit; 1.
DR FunFam; 1.25.40.70:FF:000004; Phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit beta; 1.
DR FunFam; 3.30.1010.10:FF:000005; Phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit beta; 1.
DR FunFam; 3.10.20.770:FF:000003; phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit beta isoform; 1.
DR Gene3D; 3.10.20.770; -; 1.
DR Gene3D; 2.60.40.150; C2 domain; 1.
DR Gene3D; 1.10.1070.11; Phosphatidylinositol 3-/4-kinase, catalytic domain; 1.
DR Gene3D; 3.30.1010.10; Phosphatidylinositol 3-kinase Catalytic Subunit, Chain A, domain 4; 1.
DR Gene3D; 1.25.40.70; Phosphatidylinositol 3-kinase, accessory domain (PIK); 1.
DR InterPro; IPR016024; ARM-type_fold.
DR InterPro; IPR035892; C2_domain_sf.
DR InterPro; IPR011009; Kinase-like_dom_sf.
DR InterPro; IPR000403; PI3/4_kinase_cat_dom.
DR InterPro; IPR036940; PI3/4_kinase_cat_sf.
DR InterPro; IPR018936; PI3/4_kinase_CS.
DR InterPro; IPR002420; PI3K-type_C2_dom.
DR InterPro; IPR003113; PI3K_ABD.
DR InterPro; IPR001263; PI3K_accessory_dom.
DR InterPro; IPR042236; PI3K_accessory_sf.
DR InterPro; IPR000341; PI3K_Ras-bd_dom.
DR InterPro; IPR015433; PI_Kinase.
DR InterPro; IPR029071; Ubiquitin-like_domsf.
DR PANTHER; PTHR10048:SF33; PHOSPHATIDYLINOSITOL 4,5-BISPHOSPHATE 3-KINASE CATALYTIC SUBUNIT BETA ISOFORM; 1.
DR PANTHER; PTHR10048; PHOSPHATIDYLINOSITOL KINASE; 1.
DR Pfam; PF00454; PI3_PI4_kinase; 1.
DR Pfam; PF00792; PI3K_C2; 1.
DR Pfam; PF02192; PI3K_p85B; 1.
DR Pfam; PF00794; PI3K_rbd; 1.
DR Pfam; PF00613; PI3Ka; 1.
DR SMART; SM00142; PI3K_C2; 1.
DR SMART; SM00143; PI3K_p85B; 1.
DR SMART; SM00144; PI3K_rbd; 1.
DR SMART; SM00145; PI3Ka; 1.
DR SMART; SM00146; PI3Kc; 1.
DR SUPFAM; SSF48371; ARM repeat; 1.
DR SUPFAM; SSF49562; C2 domain (Calcium/lipid-binding domain, CaLB); 1.
DR SUPFAM; SSF56112; Protein kinase-like (PK-like); 1.
DR SUPFAM; SSF54236; Ubiquitin-like; 1.
DR PROSITE; PS51547; C2_PI3K; 1.
DR PROSITE; PS00915; PI3_4_KINASE_1; 1.
DR PROSITE; PS00916; PI3_4_KINASE_2; 1.
DR PROSITE; PS50290; PI3_4_KINASE_3; 1.
DR PROSITE; PS51544; PI3K_ABD; 1.
DR PROSITE; PS51546; PI3K_RBD; 1.
DR PROSITE; PS51545; PIK_HELICAL; 1.
PE 3: Inferred from homology;
KW ATP-binding {ECO:0000256|ARBA:ARBA00022840};
KW Autophagy {ECO:0000256|ARBA:ARBA00023006};
KW Cell adhesion {ECO:0000256|ARBA:ARBA00022889};
KW Cytoplasm {ECO:0000256|ARBA:ARBA00022490};
KW Endocytosis {ECO:0000256|ARBA:ARBA00022583};
KW Kinase {ECO:0000256|ARBA:ARBA00022777};
KW Lipid metabolism {ECO:0000256|ARBA:ARBA00023098};
KW Nucleotide-binding {ECO:0000256|ARBA:ARBA00022741};
KW Nucleus {ECO:0000256|ARBA:ARBA00023242};
KW Phosphoprotein {ECO:0000256|ARBA:ARBA00022553};
KW Reference proteome {ECO:0000313|Proteomes:UP000002281};
KW Transferase {ECO:0000256|ARBA:ARBA00022679}.
FT DOMAIN 26..115
FT /note="PI3K-ABD"
FT /evidence="ECO:0000259|PROSITE:PS51544"
FT DOMAIN 194..285
FT /note="PI3K-RBD"
FT /evidence="ECO:0000259|PROSITE:PS51546"
FT DOMAIN 327..496
FT /note="C2 PI3K-type"
FT /evidence="ECO:0000259|PROSITE:PS51547"
FT DOMAIN 524..701
FT /note="PIK helical"
FT /evidence="ECO:0000259|PROSITE:PS51545"
FT DOMAIN 772..981
FT /note="PI3K/PI4K catalytic"
FT /evidence="ECO:0000259|PROSITE:PS50290"
SQ SEQUENCE 981 AA; 112434 MW; DC48CFF43D3BB85D CRC64;
MCFNFMMPPA MADSLDIWSV DSQIVSDGSI RVDFLLPTGI YIQLDVPREA PISYIKQMLW
KQVCDYPMFN LLMEIDSYMF ACVNQTAVYE ELEDETRRLC DVRPFLPVLK LVTRSCDPGE
KLDSKIGVLI GKGLHEFDAL KDPEVNEFRV KMRKFSEEKI QSLVGLSWMD WLQQTYPPEH
EPSNLENLED KLYGGKLIVA VHFENCQDVF SFQVSPNMNP IKINELAIQK RLTIRGKEDE
VSPCDYVLQV SGRVEYVFGD HPLIQFQYIR NCVMNRTLPH FILVECCKIK KMYEQEMIAI
EAAINRNSSN LPLPLPPKKT RVISHIWENN NPFQIVLVKG NKLNTEETVK VHVRAGLFHG
TELLCKTIVS SEISGKNDHI WNEPLEFDIN TCDLPRMARL CFAVYAVLDK VKTKKSTKTI
NPSKYQTIRK SGKVHYPVAW VNTMVFDFKG QLRSGDVILH SWSSFPDELE EMLNPMGTVQ
TNPYTENATA LHIKFPENKK QPYYYPPFDK IIEKAAEIAS SDSANVSSRG GKKFLAVLKE
ILDRDPLSQL CENEMDLIWT LRQDCRENFP QSLPKLLLSI KWNKLEDVAQ LQALLQIWPK
LPPREALELL DFNYPDQYVR EYAVNCLRQM SDEELSQYLL QLVQVLKYEP FLDCALSRFL
LERALANRRI GQFLFWHLRS EVHIPAVSVQ FGVILEAYCR GSVGHMKVLS KQVEALNKLK
TLNSLIKLNA VKLNRAKGKE AMHTCLKQNA YREALSDLQS PLNPCVILSE LYVEKCKYMD
SKMKPLWLVY TNKVFGEDSV GVIFKNGDDL RQDMLTLQML RLMDLLWKEA GLDLRMLPYG
CLATGDRSGL IEVVSTSETI ADIQLNSSNV AAAAAFNKDA LLNWLKEYNS GDDLDRAIEE
FTLSCAGYCV ASYVLGIGDR HSDNIMVKKT GQLFHIDFGH ILGNFKSKFG IKRERVPFIL
TYDFIHVIQQ GKTGNTEKFG R
//
