ID   KCMB1_RAT               Reviewed;         191 AA.
AC   P97678; O35337; O88805; Q9ESK7; Q9QWI7;
DT   01-NOV-1997, integrated into UniProtKB/Swiss-Prot.
DT   23-JAN-2007, sequence version 4.
DT   27-MAR-2024, entry version 147.
DE   RecName: Full=Calcium-activated potassium channel subunit beta-1;
DE   AltName: Full=BK channel subunit beta-1;
DE            Short=BKbeta;
DE            Short=BKbeta1;
DE   AltName: Full=Calcium-activated potassium channel, subfamily M subunit beta-1;
DE            Short=Calcium-activated potassium channel subunit beta;
DE   AltName: Full=Charybdotoxin receptor subunit beta-1;
DE   AltName: Full=K(VCA)beta-1;
DE   AltName: Full=Maxi K channel subunit beta-1;
DE   AltName: Full=Slo-beta-1;
DE            Short=Slo-beta;
DE   AltName: Full=Slowpoke-beta;
GN   Name=Kcnmb1;
OS   Rattus norvegicus (Rat).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC   Eutheria; Euarchontoglires; Glires; Rodentia; Myomorpha; Muroidea; Muridae;
OC   Murinae; Rattus.
OX   NCBI_TaxID=10116;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1), AND TISSUE SPECIFICITY.
RC   STRAIN=Sprague-Dawley;
RX   PubMed=9105668; DOI=10.1016/s0169-328x(96)00230-6;
RA   Chang C.-P., Dworetzky S.I., Wang J., Goldstein M.E.;
RT   "Differential expression of the alpha and beta subunits of the large-
RT   conductance calcium-activated potassium channel: implication for channel
RT   diversity.";
RL   Brain Res. Mol. Brain Res. 45:33-40(1997).
RN   [2]
RP   NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
RC   STRAIN=Sprague-Dawley; TISSUE=Uterus;
RX   PubMed=9888999; DOI=10.1006/geno.1998.5627;
RA   Jiang Z., Wallner M., Meera P., Toro L.;
RT   "Human and rodent MaxiK channel beta-subunit genes: cloning and
RT   characterization.";
RL   Genomics 55:57-67(1999).
RN   [3]
RP   NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
RC   STRAIN=Sprague-Dawley; TISSUE=Vascular smooth muscle;
RA   Lange A.R., Gebremedhin D., Aebly M., Harder D.R.;
RL   Submitted (DEC-1996) to the EMBL/GenBank/DDBJ databases.
RN   [4]
RP   NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
RC   STRAIN=Sprague-Dawley; TISSUE=Uterus;
RA   Reimann F.;
RL   Submitted (NOV-1995) to the EMBL/GenBank/DDBJ databases.
RN   [5]
RP   NUCLEOTIDE SEQUENCE [MRNA] (ISOFORMS 2 AND 3).
RC   TISSUE=Aorta;
RA   Ohya S., Watanabe M., Imaizumi Y.;
RT   "Molecular cloning of a novel spliced variant of calcium activated
RT   potassium channel beta subunit in rat smooth muscle.";
RL   Submitted (FEB-1998) to the EMBL/GenBank/DDBJ databases.
CC   -!- FUNCTION: Regulatory subunit of the calcium activated potassium KCNMA1
CC       (maxiK) channel. Modulates the calcium sensitivity and gating kinetics
CC       of KCNMA1, thereby contributing to KCNMA1 channel diversity. Increases
CC       the apparent Ca(2+)/voltage sensitivity of the KCNMA1 channel. It also
CC       modifies KCNMA1 channel kinetics and alters its pharmacological
CC       properties. It slows down the activation and the deactivation kinetics
CC       of the channel. Acts as a negative regulator of smooth muscle
CC       contraction by enhancing the calcium sensitivity to KCNMA1. Its
CC       presence is also a requirement for internal binding of the KCNMA1
CC       channel opener dehydrosoyasaponin I (DHS-1) triterpene glycoside and
CC       for external binding of the agonist hormone 17-beta-estradiol (E2).
CC       Increases the binding activity of charybdotoxin (CTX) toxin to KCNMA1
CC       peptide blocker by increasing the CTX association rate and decreasing
CC       the dissociation rate (By similarity). {ECO:0000250}.
CC   -!- SUBUNIT: Interacts with KCNMA1 tetramer. There are probably 4 molecules
CC       of KCMNB1 per KCNMA1 tetramer (By similarity). {ECO:0000250}.
CC   -!- SUBCELLULAR LOCATION: Membrane; Multi-pass membrane protein.
CC   -!- ALTERNATIVE PRODUCTS:
CC       Event=Alternative splicing; Named isoforms=3;
CC       Name=1;
CC         IsoId=P97678-1; Sequence=Displayed;
CC       Name=2; Synonyms=1b;
CC         IsoId=P97678-2; Sequence=VSP_009825, VSP_009826;
CC       Name=3; Synonyms=1c;
CC         IsoId=P97678-3; Sequence=VSP_009824, VSP_009825, VSP_009826;
CC   -!- TISSUE SPECIFICITY: Weakly expressed. In brain, it is expressed in a
CC       few discrete populations of neurons that also express KCNMA1.
CC       {ECO:0000269|PubMed:9105668}.
CC   -!- PTM: N-glycosylated. {ECO:0000250}.
CC   -!- SIMILARITY: Belongs to the KCNMB (TC 8.A.14.1) family. KCNMB1
CC       subfamily. {ECO:0000305}.
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DR   EMBL; U54498; AAD11548.1; -; mRNA.
DR   EMBL; AF020712; AAD11858.1; -; mRNA.
DR   EMBL; U79661; AAB38413.1; -; mRNA.
DR   EMBL; U40602; AAB96355.1; -; mRNA.
DR   EMBL; AB010963; BAA33448.1; -; mRNA.
DR   EMBL; AB050745; BAB17678.1; -; mRNA.
DR   RefSeq; NP_062146.1; NM_019273.1. [P97678-1]
DR   RefSeq; XP_006246151.1; XM_006246089.3. [P97678-1]
DR   RefSeq; XP_008765785.1; XM_008767563.2.
DR   RefSeq; XP_008765786.1; XM_008767564.2.
DR   AlphaFoldDB; P97678; -.
DR   SMR; P97678; -.
DR   BioGRID; 248358; 1.
DR   STRING; 10116.ENSRNOP00000007393; -.
DR   BindingDB; P97678; -.
DR   GlyCosmos; P97678; 2 sites, No reported glycans.
DR   GlyGen; P97678; 2 sites.
DR   PhosphoSitePlus; P97678; -.
DR   PaxDb; 10116-ENSRNOP00000007408; -.
DR   Ensembl; ENSRNOT00000007408.7; ENSRNOP00000007408.3; ENSRNOG00000005465.7. [P97678-1]
DR   Ensembl; ENSRNOT00000090659.2; ENSRNOP00000071161.2; ENSRNOG00000005465.7. [P97678-2]
DR   Ensembl; ENSRNOT00055004591; ENSRNOP00055003404; ENSRNOG00055002934. [P97678-1]
DR   Ensembl; ENSRNOT00060004514; ENSRNOP00060003208; ENSRNOG00060002803. [P97678-1]
DR   Ensembl; ENSRNOT00065015241; ENSRNOP00065011442; ENSRNOG00065009520. [P97678-1]
DR   GeneID; 29747; -.
DR   KEGG; rno:29747; -.
DR   UCSC; RGD:2961; rat. [P97678-1]
DR   AGR; RGD:2961; -.
DR   CTD; 3779; -.
DR   RGD; 2961; Kcnmb1.
DR   eggNOG; ENOG502RZA0; Eukaryota.
DR   GeneTree; ENSGT00950000183039; -.
DR   InParanoid; P97678; -.
DR   OMA; FPYPCLQ; -.
DR   OrthoDB; 4309705at2759; -.
DR   PhylomeDB; P97678; -.
DR   TreeFam; TF328589; -.
DR   Reactome; R-RNO-1296052; Ca2+ activated K+ channels.
DR   PRO; PR:P97678; -.
DR   Proteomes; UP000002494; Chromosome 10.
DR   Bgee; ENSRNOG00000005465; Expressed in colon and 16 other cell types or tissues.
DR   GO; GO:0016020; C:membrane; ISO:RGD.
DR   GO; GO:0005886; C:plasma membrane; TAS:Reactome.
DR   GO; GO:0008076; C:voltage-gated potassium channel complex; ISO:RGD.
DR   GO; GO:0015269; F:calcium-activated potassium channel activity; ISO:RGD.
DR   GO; GO:0015459; F:potassium channel regulator activity; IDA:RGD.
DR   GO; GO:1903413; P:cellular response to bile acid; IDA:RGD.
DR   GO; GO:0071361; P:cellular response to ethanol; IDA:RGD.
DR   GO; GO:0071456; P:cellular response to hypoxia; IEP:RGD.
DR   GO; GO:0005513; P:detection of calcium ion; IBA:GO_Central.
DR   GO; GO:1901381; P:positive regulation of potassium ion transmembrane transport; IDA:RGD.
DR   GO; GO:0071805; P:potassium ion transmembrane transport; ISO:RGD.
DR   GO; GO:0051592; P:response to calcium ion; IDA:RGD.
DR   GO; GO:0042311; P:vasodilation; IDA:RGD.
DR   InterPro; IPR003930; K_chnl_Ca-activ_BK_bsu.
DR   PANTHER; PTHR10258; CALCIUM-ACTIVATED POTASSIUM CHANNEL SUBUNIT BETA; 1.
DR   PANTHER; PTHR10258:SF1; CALCIUM-ACTIVATED POTASSIUM CHANNEL SUBUNIT BETA-1; 1.
DR   Pfam; PF03185; CaKB; 1.
DR   PRINTS; PR01450; BKCHANNELB.
DR   Genevisible; P97678; RN.
PE   2: Evidence at transcript level;
KW   Alternative splicing; Glycoprotein; Ion channel; Ion transport; Membrane;
KW   Reference proteome; Transmembrane; Transmembrane helix; Transport.
FT   CHAIN           1..191
FT                   /note="Calcium-activated potassium channel subunit beta-1"
FT                   /id="PRO_0000187049"
FT   TOPO_DOM        1..18
FT                   /note="Cytoplasmic"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        19..39
FT                   /note="Helical; Name=1"
FT                   /evidence="ECO:0000255"
FT   TOPO_DOM        40..155
FT                   /note="Extracellular"
FT                   /evidence="ECO:0000255"
FT   TRANSMEM        156..176
FT                   /note="Helical; Name=2"
FT                   /evidence="ECO:0000255"
FT   TOPO_DOM        177..191
FT                   /note="Cytoplasmic"
FT                   /evidence="ECO:0000255"
FT   CARBOHYD        80
FT                   /note="N-linked (GlcNAc...) asparagine"
FT                   /evidence="ECO:0000255"
FT   CARBOHYD        142
FT                   /note="N-linked (GlcNAc...) asparagine"
FT                   /evidence="ECO:0000255"
FT   VAR_SEQ         103..122
FT                   /note="Missing (in isoform 3)"
FT                   /evidence="ECO:0000303|Ref.5"
FT                   /id="VSP_009824"
FT   VAR_SEQ         123..146
FT                   /note="VRANFYKHHNFYCFSAPQVNETSV -> LRSRPISSAQQHGVTRNGRGPGQA
FT                   (in isoform 2 and isoform 3)"
FT                   /evidence="ECO:0000303|Ref.5"
FT                   /id="VSP_009825"
FT   VAR_SEQ         147..191
FT                   /note="Missing (in isoform 2 and isoform 3)"
FT                   /evidence="ECO:0000303|Ref.5"
FT                   /id="VSP_009826"
FT   CONFLICT        14
FT                   /note="T -> A (in Ref. 2; AAB38413)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        28..30
FT                   /note="AIT -> VVA (in Ref. 2; AAB38413)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        38
FT                   /note="V -> M (in Ref. 2; AAB38413)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        56..61
FT                   /note="VETNIK -> IESNIR (in Ref. 2; AAB38413)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        69
FT                   /note="R -> K (in Ref. 2; AAB38413)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        89
FT                   /note="M -> V (in Ref. 2; AAB38413)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        105
FT                   /note="Y -> H (in Ref. 1; AAD11548)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        109..111
FT                   /note="NLD -> SLE (in Ref. 2; AAB38413)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        115..121
FT                   /note="TALVDVK -> VARADVE (in Ref. 2; AAB38413)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        125
FT                   /note="A -> T (in Ref. 2; AAB38413)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        128..132
FT                   /note="YKHHN -> HEHRI (in Ref. 2; AAB38413)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        138..141
FT                   /note="APQV -> TTRE (in Ref. 2; AAB38413)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        145..149
FT                   /note="SVVYQ -> TVLYR (in Ref. 2; AAB38413)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        156
FT                   /note="I -> T (in Ref. 2; AAB38413)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        161
FT                   /note="F -> L (in Ref. 2; AAB38413)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        177
FT                   /note="M -> I (in Ref. 1; AAD11548)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        180..182
FT                   /note="LNR -> INQ (in Ref. 2; AAB38413)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        186..187
FT                   /note="VL -> IP (in Ref. 1; AAD11548)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        186
FT                   /note="V -> I (in Ref. 2; AAB38413)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        191
FT                   /note="K -> R (in Ref. 1 and 2)"
FT                   /evidence="ECO:0000305"
SQ   SEQUENCE   191 AA;  21909 MW;  D39F2FE4D69D7662 CRC64;
     MGKKLVMAQK RGETRALCLG VAMVVCAAIT YYILGTTVLP LYQKSVWTQE STCHLVETNI
     KDQEELEGRK VPQYPCLWVN VSAVGRWAML YHTEDTRDQN QQCSYIPRNL DNYQTALVDV
     KKVRANFYKH HNFYCFSAPQ VNETSVVYQR LYGPQILLFS FFWPTFLLTG GLLIIAMVKL
     NRSLSVLAAQ K
//