UniProtKB - Q28265 (KCMA1_CANLF)
Calcium-activated potassium channel subunit alpha-1
KCNMA1
Functioni
Potassium channel activated by both membrane depolarization or increase in cytosolic Ca2+ that mediates export of K+. It is also activated by the concentration of cytosolic Mg2+. Its activation dampens the excitatory events that elevate the cytosolic Ca2+ concentration and/or depolarize the cell membrane. It therefore contributes to repolarization of the membrane potential. Plays a key role in controlling excitability in a number of systems, such as regulation of the contraction of smooth muscle, the tuning of hair cells in the cochlea, regulation of transmitter release, and innate immunity. In smooth muscles, its activation by high level of Ca2+, caused by ryanodine receptors in the sarcoplasmic reticulum, regulates the membrane potential. In cochlea cells, its number and kinetic properties partly determine the characteristic frequency of each hair cell and thereby helps to establish a tonotopic map. Kinetics of KCNMA1 channels are determined by alternative splicing, phosphorylation status and its combination with modulating beta subunits. Highly sensitive to both iberiotoxin (IbTx) and charybdotoxin (CTX) (By similarity).
By similarity1 PublicationMiscellaneous
Activity regulationi
Sites
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Metal bindingi | 377 | MagnesiumBy similarity | 1 | |
Metal bindingi | 400 | MagnesiumBy similarity | 1 | |
Metal bindingi | 402 | MagnesiumBy similarity | 1 | |
Metal bindingi | 892 | Calcium; via carbonyl oxygenBy similarity | 1 | |
Metal bindingi | 895 | Calcium; via carbonyl oxygenBy similarity | 1 | |
Metal bindingi | 898 | CalciumBy similarity | 1 | |
Metal bindingi | 900 | CalciumBy similarity | 1 |
GO - Molecular functioni
- actin binding Source: AgBase
- calcium-activated potassium channel activity Source: AgBase
- large conductance calcium-activated potassium channel activity Source: AgBase
- metal ion binding Source: UniProtKB-KW
- potassium channel activity Source: AgBase
- voltage-gated potassium channel activity Source: AgBase
GO - Biological processi
- adult walking behavior Source: AgBase
- cell maturation Source: AgBase
- cellular potassium ion homeostasis Source: AgBase
- chemical synaptic transmission Source: AgBase
- circadian rhythm Source: AgBase
- eye blink reflex Source: AgBase
- inner ear auditory receptor cell differentiation Source: AgBase
- locomotor rhythm Source: AgBase
- micturition Source: AgBase
- negative regulation of cell volume Source: AgBase
- neuromuscular process controlling balance Source: AgBase
- neuronal action potential Source: AgBase
- positive regulation of apoptotic process Source: AgBase
- potassium ion transmembrane transport Source: AgBase
- potassium ion transport Source: AgBase
- protein homooligomerization Source: AgBase
- regulation of aldosterone metabolic process Source: AgBase
- regulation of ion transmembrane transport Source: UniProtKB-KW
- regulation of membrane potential Source: AgBase
- relaxation of vascular associated smooth muscle Source: AgBase
- response to calcium ion Source: AgBase
- response to carbon monoxide Source: AgBase
- response to hypoxia Source: AgBase
- response to osmotic stress Source: AgBase
- saliva secretion Source: AgBase
- sensory perception of sound Source: AgBase
- smooth muscle contraction involved in micturition Source: AgBase
- vasodilation Source: AgBase
Keywordsi
Molecular function | Ion channel, Potassium channel, Voltage-gated channel |
Biological process | Ion transport, Potassium transport, Transport |
Ligand | Calcium, Magnesium, Metal-binding, Potassium |
Names & Taxonomyi
Protein namesi | Recommended name: Calcium-activated potassium channel subunit alpha-1Alternative name(s): BK channel BKCA alpha Calcium-activated potassium channel, subfamily M subunit alpha-1 K(VCA)alpha KCa1.1 Maxi K channel Short name: MaxiK Slo-alpha Slo1 Slowpoke homolog Short name: Slo homolog |
Gene namesi | Name:KCNMA1 Synonyms:KCNMA |
Organismi | Canis lupus familiaris (Dog) (Canis familiaris) |
Taxonomic identifieri | 9615 [NCBI] |
Taxonomic lineagei | Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Laurasiatheria › Carnivora › Caniformia › Canidae › Canis › |
Proteomesi |
|
Subcellular locationi
Plasma membrane
- Cell membrane By similarity; Multi-pass membrane protein By similarity
Endoplasmic reticulum
- endoplasmic reticulum Source: AgBase
Extracellular region or secreted
- extracellular exosome Source: AgBase
Plasma Membrane
- apical plasma membrane Source: AgBase
- caveola Source: AgBase
- external side of plasma membrane Source: AgBase
- plasma membrane Source: AgBase
- postsynaptic membrane Source: AgBase
- voltage-gated potassium channel complex Source: AgBase
Other locations
- cytoplasm Source: AgBase
- integral component of membrane Source: AgBase
- terminal bouton Source: AgBase
Topology
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Topological domaini | ‹1 – 24 | ExtracellularSequence analysisAdd BLAST | ›24 | |
Transmembranei | 25 – 45 | Helical; Name=Segment S0Sequence analysisAdd BLAST | 21 | |
Topological domaini | 46 – 116 | CytoplasmicSequence analysisAdd BLAST | 71 | |
Transmembranei | 117 – 137 | Helical; Name=Segment S1Sequence analysisAdd BLAST | 21 | |
Topological domaini | 138 – 152 | ExtracellularSequence analysisAdd BLAST | 15 | |
Transmembranei | 153 – 173 | Helical; Name=Segment S2Sequence analysisAdd BLAST | 21 | |
Topological domaini | 174 – 177 | CytoplasmicSequence analysis | 4 | |
Transmembranei | 178 – 198 | Helical; Name=Segment S3Sequence analysisAdd BLAST | 21 | |
Topological domaini | 199 – 202 | ExtracellularSequence analysis | 4 | |
Transmembranei | 203 – 223 | Helical; Voltage-sensor; Name=Segment S4Sequence analysisAdd BLAST | 21 | |
Topological domaini | 224 – 238 | CytoplasmicSequence analysisAdd BLAST | 15 | |
Transmembranei | 239 – 259 | Helical; Name=Segment S5Sequence analysisAdd BLAST | 21 | |
Topological domaini | 260 – 273 | ExtracellularSequence analysisAdd BLAST | 14 | |
Intramembranei | 274 – 296 | Pore-forming; Name=P regionSequence analysisAdd BLAST | 23 | |
Topological domaini | 297 – 305 | ExtracellularSequence analysis | 9 | |
Transmembranei | 306 – 326 | Helical; Name=Segment S6Sequence analysisAdd BLAST | 21 | |
Topological domaini | 327 – 1159 | CytoplasmicSequence analysisAdd BLAST | 833 |
Keywords - Cellular componenti
Cell membrane, MembranePTM / Processingi
Molecule processing
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
ChainiPRO_0000054131 | ‹1 – 1159 | Calcium-activated potassium channel subunit alpha-1Add BLAST | ›1159 |
Amino acid modifications
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Lipidationi | 56 | S-palmitoyl cysteineBy similarity | 1 | |
Lipidationi | 57 | S-palmitoyl cysteineBy similarity | 1 | |
Lipidationi | 59 | S-palmitoyl cysteineBy similarity | 1 | |
Modified residuei | 643 | PhosphothreonineBy similarity | 1 | |
Modified residuei | 645 | PhosphoserineBy similarity | 1 | |
Modified residuei | 658 | PhosphoserineBy similarity | 1 | |
Modified residuei | 662 | PhosphoserineBy similarity | 1 | |
Modified residuei | 850 | PhosphothreonineBy similarity | 1 | |
Modified residuei | 858 | PhosphoserineBy similarity | 1 | |
Modified residuei | 862 | PhosphoserineBy similarity | 1 | |
Modified residuei | 1101 | PhosphoserineBy similarity | 1 | |
Modified residuei | 1104 | PhosphoserineBy similarity | 1 |
Post-translational modificationi
Keywords - PTMi
Lipoprotein, Palmitate, PhosphoproteinProteomic databases
PaxDbi | Q28265 |
PRIDEi | Q28265 |
PTM databases
iPTMneti | Q28265 |
Expressioni
Tissue specificityi
Interactioni
Subunit structurei
Homotetramer; which constitutes the calcium-activated potassium channel.
Interacts with beta subunits KCNMB1, KCNMB2, KCNMB3 and KCNMB4.
Interacts with gamma subunits LRRC26, LRRC38, LRRC52 and LRRC55. Beta and gamma subunits are accessory, and modulate its activity.
Interacts with RAB11B (By similarity).
By similarityGO - Molecular functioni
- actin binding Source: AgBase
Protein-protein interaction databases
STRINGi | 9612.ENSCAFP00000022784 |
Family & Domainsi
Domains and Repeats
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Domaini | 353 – 496 | RCK N-terminalAdd BLAST | 144 |
Region
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Regioni | 494 – 514 | Segment S7Add BLAST | 21 | |
Regioni | 551 – 571 | Segment S8Add BLAST | 21 | |
Regioni | 615 – 619 | Heme-binding motif | 5 | |
Regioni | 639 – 668 | DisorderedSequence analysisAdd BLAST | 30 | |
Regioni | 717 – 737 | Segment S9Add BLAST | 21 | |
Regioni | 912 – 932 | Segment S10Add BLAST | 21 | |
Regioni | 1066 – 1124 | DisorderedSequence analysisAdd BLAST | 59 |
Motif
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Motifi | 290 – 293 | Selectivity for potassium | 4 | |
Motifi | 883 – 905 | Calcium bowlAdd BLAST | 23 |
Compositional bias
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Compositional biasi | 646 – 664 | Polar residuesSequence analysisAdd BLAST | 19 | |
Compositional biasi | 1066 – 1097 | Polar residuesSequence analysisAdd BLAST | 32 | |
Compositional biasi | 1098 – 1118 | Basic and acidic residuesSequence analysisAdd BLAST | 21 |
Domaini
Sequence similaritiesi
Keywords - Domaini
Transmembrane, Transmembrane helixPhylogenomic databases
eggNOGi | KOG1420, Eukaryota |
InParanoidi | Q28265 |
OrthoDBi | 124461at2759 |
Family and domain databases
InterProi | View protein in InterPro IPR024939, Ca-act_K_channel_Slo-1 IPR005821, Ion_trans_dom IPR003929, K_chnl_BK_asu IPR036291, NAD(P)-bd_dom_sf |
PANTHERi | PTHR10027:SF28, PTHR10027:SF28, 2 hits |
Pfami | View protein in Pfam PF03493, BK_channel_a, 1 hit PF00520, Ion_trans, 1 hit |
SUPFAMi | SSF51735, SSF51735, 1 hit |
i Sequence
Sequence statusi: Fragment.
This entry describes 1 produced by isoform ialternative splicing. AlignAdd to basketThis isoform has been chosen as the sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry. canonicali
10 20 30 40 50
EPNMDALIIP VTMEVPCDSR GQRMWWAFLA SSMVTFFGGL FIILLWRTLK
60 70 80 90 100
YLWTVCCHCG DKTKEAQKIN NGSSQADGTL KPVDEKEEAV AAEVGWMTSV
110 120 130 140 150
KDWAGVMISA QTLTGRVLVV LVFALSIGAL VIYFIDSSNP IESCQNFYKD
160 170 180 190 200
FTLQIDMAFN VFFLLYFGLR FIAANDNLWF WLEVNSVVDF FTVPPVFVSV
210 220 230 240 250
YLNRSWLGLR FLRALRLIQF SEILQFLNIL KTSNSIKLVN LLSIFISTWL
260 270 280 290 300
TAAGFIHLVE NSGDPWENFQ NSQALTYWEC VYLLMVTMST VGYGDVYAKT
310 320 330 340 350
TPGGLFIVFF ILGGLAMFAS YVPEIIEIIG NRKKYGGSYS AVSGRKHIVV
360 370 380 390 400
CGHITLESVS HFLKDFLHKD RDDVNVEIVF LHNISPNLEL EALFKRHFTQ
410 420 430 440 450
VEFYQGSVLN PHDLARVKIE SADACLILAN KYCDDPDAED ASNIMRVISI
460 470 480 490 500
KNYHPKIRII TQMLQYHNKA HLLNIPSWNW KEGDDAICLA ELRLGFIAQS
510 520 530 540 550
CLAQGLSTML ANLFSIGSFI KIEEDTWHKY YLEGVSNEMY TEYLSSAFVG
560 570 580 590 600
LSFPTVCELC FVKLKLLMIA IEYKSANRES RILINPGNHL KIQEGTSGFF
610 620 630 640 650
IASDAKEVKR AFFYCKACHN DITDPKRIKK CGCKRLEDEQ PSTLSPKKKQ
660 670 680 690 700
RNGGMRNSPS SSPKLMRHDP LLIPGNDQID NMDSNVKKYD STGMFHWCAP
710 720 730 740 750
KEIEKVISTR SEAAMTVLSG HVVVCIFGHV SSALIGLRNL VMPLRASNFH
760 770 780 790 800
YHELKHIVFV GSIEYLKREW ETLHNFPKVS ILPGTPLTRA DLRAVNINLC
810 820 830 840 850
DMCVILSANQ NNIDDTSLQD KECILASLNI KSMQFDDSIG VLQANSQGFT
860 870 880 890 900
PPGMDKSSPD NSPVHGMLRQ PSITTGVNIP IITELVNDTN VQFLDQDDDD
910 920 930 940 950
DPDTELYLTQ PFACGTAFAV SVLDSLMSAT YFNDNILTLI RTLVTGGATP
960 970 980 990 1000
ELEALIAEEN ALRGGYSTPQ TLANRDRCRV AQLALLDGPF ADLGDGGCYG
1010 1020 1030 1040 1050
DLFCKALKTY NMLCFGIYRL RDAHLSTPSQ CTKRYVITNP PYRFELVPTD
1060 1070 1080 1090 1100
LIFCLMQFDH NAGQSRASLS HSSHSSQSSS KKSSSVHSIP STANRQNRPK
1110 1120 1130 1140 1150
SRESRDKQTE KKWFTDEPDN AYPRNIQIEP MSTHMANQIN QYKSTSSLIP
PIREVEDEC
Experimental Info
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Non-terminal residuei | 1 | 1 |
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | U41001 mRNA Translation: AAA84000.1 |
RefSeqi | NP_001003300.2, NM_001003300.2 |
Genome annotation databases
GeneIDi | 403984 |
KEGGi | cfa:403984 |
Keywords - Coding sequence diversityi
Alternative splicingSimilar proteinsi
Cross-referencesi
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | U41001 mRNA Translation: AAA84000.1 |
RefSeqi | NP_001003300.2, NM_001003300.2 |
3D structure databases
SMRi | Q28265 |
ModBasei | Search... |
Protein-protein interaction databases
STRINGi | 9612.ENSCAFP00000022784 |
PTM databases
iPTMneti | Q28265 |
Proteomic databases
PaxDbi | Q28265 |
PRIDEi | Q28265 |
Genome annotation databases
GeneIDi | 403984 |
KEGGi | cfa:403984 |
Organism-specific databases
CTDi | 3778 |
Phylogenomic databases
eggNOGi | KOG1420, Eukaryota |
InParanoidi | Q28265 |
OrthoDBi | 124461at2759 |
Family and domain databases
InterProi | View protein in InterPro IPR024939, Ca-act_K_channel_Slo-1 IPR005821, Ion_trans_dom IPR003929, K_chnl_BK_asu IPR036291, NAD(P)-bd_dom_sf |
PANTHERi | PTHR10027:SF28, PTHR10027:SF28, 2 hits |
Pfami | View protein in Pfam PF03493, BK_channel_a, 1 hit PF00520, Ion_trans, 1 hit |
SUPFAMi | SSF51735, SSF51735, 1 hit |
MobiDBi | Search... |
Entry informationi
Entry namei | KCMA1_CANLF | |
Accessioni | Q28265Primary (citable) accession number: Q28265 | |
Entry historyi | Integrated into UniProtKB/Swiss-Prot: | April 13, 2004 |
Last sequence update: | April 13, 2004 | |
Last modified: | September 29, 2021 | |
This is version 147 of the entry and version 2 of the sequence. See complete history. | ||
Entry statusi | Reviewed (UniProtKB/Swiss-Prot) | |
Annotation program | Chordata Protein Annotation Program |
Miscellaneousi
Keywords - Technical termi
Reference proteomeDocuments
- SIMILARITY comments
Index of protein domains and families