KCAB1_RABIT
ID KCAB1_RABIT Reviewed; 419 AA.
AC Q9XT31; Q9XT32; Q9XT33;
DT 18-OCT-2001, integrated into UniProtKB/Swiss-Prot.
DT 01-NOV-1999, sequence version 1.
DT 03-AUG-2022, entry version 112.
DE RecName: Full=Voltage-gated potassium channel subunit beta-1;
DE EC=1.1.1.- {ECO:0000250|UniProtKB:P63144};
DE AltName: Full=K(+) channel subunit beta-1;
DE AltName: Full=Kv-beta-1;
GN Name=KCNAB1; Synonyms=KVBETA1;
OS Oryctolagus cuniculus (Rabbit).
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC Eutheria; Euarchontoglires; Glires; Lagomorpha; Leporidae; Oryctolagus.
OX NCBI_TaxID=9986;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA] (ISOFORMS KVB1.1; KVB1.2 AND KVB1.3).
RC STRAIN=New Zealand white;
RA Thorneloe K.S., Walsh M.P., Cole W.C.;
RL Submitted (MAR-1999) to the EMBL/GenBank/DDBJ databases.
RN [2]
RP INTERACTION WITH KCNA2 AND KCNA5, SUBCELLULAR LOCATION, AND TISSUE
RP SPECIFICITY.
RX PubMed=11717160; DOI=10.1161/hh2301.100817;
RA Thorneloe K.S., Chen T.T., Kerr P.M., Grier E.F., Horowitz B., Cole W.C.,
RA Walsh M.P.;
RT "Molecular composition of 4-aminopyridine-sensitive voltage-gated K(+)
RT channels of vascular smooth muscle.";
RL Circ. Res. 89:1030-1037(2001).
CC -!- FUNCTION: Cytoplasmic potassium channel subunit that modulates the
CC characteristics of the channel-forming alpha-subunits (By similarity).
CC Modulates action potentials via its effect on the pore-forming alpha
CC subunits (By similarity). Promotes expression of the pore-forming alpha
CC subunits at the cell membrane, and thereby increases channel activity
CC (By similarity). Mediates closure of delayed rectifier potassium
CC channels by physically obstructing the pore via its N-terminal domain
CC and increases the speed of channel closure for other family members (By
CC similarity). Promotes the closure of KCNA1, KCNA2 and KCNA5 channels
CC (By similarity). Accelerates KCNA4 channel closure (By similarity).
CC Accelerates the closure of heteromeric channels formed by KCNA1 and
CC KCNA4 (By similarity). Accelerates the closure of heteromeric channels
CC formed by KCNA2, KCNA5 and KCNA6 (By similarity). Enhances KCNB1 and
CC KCNB2 channel activity (By similarity). Binds NADPH; this is required
CC for efficient down-regulation of potassium channel activity (By
CC similarity). Has NADPH-dependent aldoketoreductase activity (By
CC similarity). Oxidation of the bound NADPH strongly decreases N-type
CC inactivation of potassium channel activity (By similarity).
CC {ECO:0000250|UniProtKB:P63143, ECO:0000250|UniProtKB:P63144,
CC ECO:0000250|UniProtKB:Q14722}.
CC -!- SUBUNIT: Homotetramer (By similarity). Interaction with tetrameric
CC potassium channel alpha subunits gives rise to a heterooctamer
CC (Probable). Identified in potassium channel complexes containing KCNA1,
CC KCNA2, KCNA4, KCNA5, KCNA6, KCNAB1 and KCNAB2 (By similarity).
CC Interacts with KCNA1 (PubMed:11717160). Interacts with the dimer formed
CC by GNB1 and GNG2; this enhances KCNA1 binding (By similarity).
CC Interacts with KCNA4 (By similarity). Interacts with KCNA5
CC (PubMed:11717160). Interacts with KCNB2 (By similarity). Interacts with
CC SQSTM1 (By similarity). Part of a complex containing KCNA1, KCNA4 and
CC LGI1; interaction with LGI1 inhibits down-regulation of KCNA1 channel
CC activity (By similarity). {ECO:0000250|UniProtKB:P63143,
CC ECO:0000250|UniProtKB:P63144, ECO:0000250|UniProtKB:Q14722,
CC ECO:0000269|PubMed:11717160, ECO:0000305}.
CC -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000269|PubMed:11717160}. Membrane
CC {ECO:0000250|UniProtKB:P63144}; Peripheral membrane protein
CC {ECO:0000250|UniProtKB:P63144}; Cytoplasmic side
CC {ECO:0000250|UniProtKB:P63144}. Cell membrane
CC {ECO:0000250|UniProtKB:Q14722}; Peripheral membrane protein
CC {ECO:0000250|UniProtKB:Q14722}; Cytoplasmic side
CC {ECO:0000250|UniProtKB:Q14722}. Note=Recruited to the cytoplasmic side
CC of the cell membrane via its interaction with pore-forming potassium
CC channel alpha subunits. {ECO:0000250|UniProtKB:Q14722}.
CC -!- ALTERNATIVE PRODUCTS:
CC Event=Alternative splicing; Named isoforms=3;
CC Name=KvB1.3;
CC IsoId=Q9XT31-1; Sequence=Displayed;
CC Name=KvB1.1;
CC IsoId=Q9XT31-2; Sequence=VSP_001053;
CC Name=KvB1.2;
CC IsoId=Q9XT31-3; Sequence=VSP_001052;
CC -!- TISSUE SPECIFICITY: Detected in portal vein myocytes (at protein level)
CC (PubMed:11717160).
CC -!- DOMAIN: The N-terminal domain of the beta subunit mediates closure of
CC delayed rectifier potassium channels by physically obstructing the
CC pore. {ECO:0000250|UniProtKB:P63144}.
CC -!- SIMILARITY: Belongs to the shaker potassium channel beta subunit
CC family. {ECO:0000305}.
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DR EMBL; AF131934; AAD37853.1; -; mRNA.
DR EMBL; AF131935; AAD37854.1; -; mRNA.
DR EMBL; AF131936; AAD37855.1; -; mRNA.
DR RefSeq; NP_001164427.1; NM_001170956.1. [Q9XT31-1]
DR RefSeq; XP_008264420.1; XM_008266198.2. [Q9XT31-3]
DR AlphaFoldDB; Q9XT31; -.
DR SMR; Q9XT31; -.
DR STRING; 9986.ENSOCUP00000023218; -.
DR Ensembl; ENSOCUT00000025128; ENSOCUP00000023218; ENSOCUG00000007885. [Q9XT31-3]
DR Ensembl; ENSOCUT00000034594; ENSOCUP00000044774; ENSOCUG00000007885. [Q9XT31-1]
DR GeneID; 100328569; -.
DR KEGG; ocu:100328569; -.
DR CTD; 7881; -.
DR eggNOG; KOG1575; Eukaryota.
DR GeneTree; ENSGT00940000156760; -.
DR InParanoid; Q9XT31; -.
DR OrthoDB; 1106773at2759; -.
DR Proteomes; UP000001811; Chromosome 14.
DR Bgee; ENSOCUG00000007885; Expressed in aorta and 14 other tissues.
DR ExpressionAtlas; Q9XT31; baseline.
DR GO; GO:0005829; C:cytosol; ISS:UniProtKB.
DR GO; GO:0031234; C:extrinsic component of cytoplasmic side of plasma membrane; ISS:UniProtKB.
DR GO; GO:0034705; C:potassium channel complex; ISS:UniProtKB.
DR GO; GO:0008076; C:voltage-gated potassium channel complex; IEA:Ensembl.
DR GO; GO:0004033; F:aldo-keto reductase (NADP) activity; ISS:UniProtKB.
DR GO; GO:0070402; F:NADPH binding; ISS:UniProtKB.
DR GO; GO:0015459; F:potassium channel regulator activity; ISS:UniProtKB.
DR GO; GO:0019904; F:protein domain specific binding; IEA:Ensembl.
DR GO; GO:0005249; F:voltage-gated potassium channel activity; IEA:InterPro.
DR GO; GO:1903817; P:negative regulation of voltage-gated potassium channel activity; IEA:Ensembl.
DR GO; GO:1902259; P:regulation of delayed rectifier potassium channel activity; ISS:UniProtKB.
DR GO; GO:1901379; P:regulation of potassium ion transmembrane transport; ISS:UniProtKB.
DR Gene3D; 3.20.20.100; -; 1.
DR InterPro; IPR005983; K_chnl_volt-dep_bsu_KCNAB.
DR InterPro; IPR005399; K_chnl_volt-dep_bsu_KCNAB-rel.
DR InterPro; IPR005400; K_chnl_volt-dep_bsu_KCNAB1.
DR InterPro; IPR023210; NADP_OxRdtase_dom.
DR InterPro; IPR036812; NADP_OxRdtase_dom_sf.
DR PANTHER; PTHR43150; PTHR43150; 1.
DR Pfam; PF00248; Aldo_ket_red; 1.
DR PRINTS; PR01578; KCNAB1CHANEL.
DR PRINTS; PR01577; KCNABCHANNEL.
DR SUPFAM; SSF51430; SSF51430; 1.
DR TIGRFAMs; TIGR01293; Kv_beta; 1.
PE 1: Evidence at protein level;
KW Alternative splicing; Cell membrane; Cytoplasm; Ion channel; Ion transport;
KW Membrane; NADP; Oxidoreductase; Potassium; Potassium transport;
KW Reference proteome; Transport; Voltage-gated channel.
FT CHAIN 1..419
FT /note="Voltage-gated potassium channel subunit beta-1"
FT /id="PRO_0000148742"
FT REGION 1..51
FT /note="Disordered"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT ACT_SITE 142
FT /note="Proton donor/acceptor"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT BINDING 108..109
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT BINDING 115
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT BINDING 137
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT BINDING 142
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT BINDING 240..241
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT BINDING 266
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT BINDING 295..300
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT BINDING 306
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT BINDING 375..381
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT VAR_SEQ 1..91
FT /note="MLAARTGAAGSQIAEESSKLRKQAAFSGGSKDRSPKKASENVKDSSLSPSGQ
FT SQVRARQLALLREVEMNWYLKLCELSSEHTTAYTTGMPH -> MQVSIACTEHNLKSRN
FT GEDRLLSKQSSNAPNVVNAARAKFRTVAIIARSLGTFTPQHHISLKESTAKQTGMKY
FT (in isoform KvB1.1)"
FT /evidence="ECO:0000303|Ref.1"
FT /id="VSP_001053"
FT VAR_SEQ 1..91
FT /note="MLAARTGAAGSQIAEESSKLRKQAAFSGGSKDRSPKKASENVKDSSLSPSGQ
FT SQVRARQLALLREVEMNWYLKLCELSSEHTTAYTTGMPH -> MHLYKPACADIPSPKL
FT GLPKSSESALKCRRHLMVTKTQPQAACWPVRPSGPTERKHLERFLCVHGVSLQETTKAE
FT TGMAY (in isoform KvB1.2)"
FT /evidence="ECO:0000303|Ref.1"
FT /id="VSP_001052"
SQ SEQUENCE 419 AA; 46537 MW; 721A8DA5087EB93C CRC64;
MLAARTGAAG SQIAEESSKL RKQAAFSGGS KDRSPKKASE NVKDSSLSPS GQSQVRARQL
ALLREVEMNW YLKLCELSSE HTTAYTTGMP HRNLGKSGLR VSCLGLGTWV TFGGQISDEV
AERLMTIAYE SGVNLFDTAE VYAAGKAEVI LGSIIKKKGW RRSSLVITTK LYWGGKAETE
RGLSRKHIIE GLKGSLQRLQ LEYVDVVFAN RPDSNTPMEE IVRAMTHVIN QGMAMYWGTS
RWSAMEIMEA YSVARQFNMI PPVCEQAEYH LFQREKVEVQ LPELYHKIGV GAMTWSPLAC
GIISGKYGNG VPESSRASLK CYQWLKERIV SEEGRKQQNK LKDLSPIAER LGCTLPQLAV
AWCLRNEGVS SVLLGSSTPE QLIENLGAIQ VLPKMTSHVV NEIDNILRNK PYSKKDYRS
