KCAB1_MUSPU
ID KCAB1_MUSPU Reviewed; 408 AA.
AC Q28528;
DT 18-OCT-2001, integrated into UniProtKB/Swiss-Prot.
DT 01-NOV-1996, sequence version 1.
DT 03-AUG-2022, entry version 102.
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=KVB3;
OS Mustela putorius (European polecat).
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC Eutheria; Laurasiatheria; Carnivora; Caniformia; Mustelidae; Mustelinae;
OC Mustela.
OX NCBI_TaxID=9668;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, AND TISSUE SPECIFICITY.
RC TISSUE=Heart;
RX PubMed=7890764; DOI=10.1074/jbc.270.11.6272;
RA Morales M.J., Castellino R.C., Crews A.L., Rasmusson R.L., Strauss H.C.;
RT "A novel beta subunit increases rate of inactivation of specific voltage-
RT gated potassium channel alpha subunits.";
RL J. Biol. Chem. 270:6272-6277(1995).
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 (PubMed:7890764).
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, ECO:0000269|PubMed:7890764}.
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 (By similarity). 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 (By
CC similarity). 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:0000305}.
CC -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000250|UniProtKB:Q14722}.
CC Membrane {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 -!- TISSUE SPECIFICITY: Expression most abundant in aorta. Also high in
CC left ventricle. Also detected in right ventricle, atrium, brain,
CC skeletal muscle and kidney. Not detected in liver.
CC {ECO:0000269|PubMed:7890764}.
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; U17966; AAC48462.1; -; mRNA.
DR AlphaFoldDB; Q28528; -.
DR SMR; Q28528; -.
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: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:0005249; F:voltage-gated potassium channel activity; IEA:InterPro.
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 2: Evidence at transcript level;
KW Cell membrane; Cytoplasm; Ion channel; Ion transport; Membrane; NADP;
KW Oxidoreductase; Potassium; Potassium transport; Transport;
KW Voltage-gated channel.
FT CHAIN 1..408
FT /note="Voltage-gated potassium channel subunit beta-1"
FT /id="PRO_0000148741"
FT ACT_SITE 131
FT /note="Proton donor/acceptor"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT BINDING 97..98
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT BINDING 104
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT BINDING 126
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT BINDING 131
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT BINDING 229..230
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT BINDING 255
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT BINDING 284..289
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT BINDING 295
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000250|UniProtKB:P62483"
FT BINDING 364..370
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000250|UniProtKB:P62483"
SQ SEQUENCE 408 AA; 45483 MW; AB74664C1AB15F30 CRC64;
MHLYKPACAD IPSPKLGLPK SSESALKCRR HLAVTKPPPQ AACWPARPSG AAERKFLEKF
LRVHGISLQE TTRAETGMAY RNLGKSGLRV SCLGLGTWVT FGGQISDEVA ERLMTIAYES
GVNLFDTAEV YAAGKAEVIL GSIIKKKGWR RSSLVITTKL YWGGKAETER GLSRKHIIEG
LKGSLQRLQL EYVDVVFANR PDSNTPMEEI VRAMTHVINQ GMAMYWGTSR WSAMEIMEAY
SVARQFNMIP PVCEQAEYHL FQREKVEVQL PELYHKIGVG AMTWSPLACG IISGKYGNGV
PESSRASLKC YQWLKERIVS EEGRKQQNKL KDLSPIAERL GCTLPQLAVA WCLRNEGVSS
VLLGSSTPEQ LIENLGAIQV LPKMTSHVVN EIDNILRNKP YSKKDYRS
