UniProtKB - Q63099 (KCNB2_RAT)
Protein
Potassium voltage-gated channel subfamily B member 2
Gene
Kcnb2
Organism
Rattus norvegicus (Rat)
Status
Functioni
Voltage-gated potassium channel that mediates transmembrane potassium transport in excitable membranes, primarily in the brain and smooth muscle cells (PubMed:1550672). Channels open or close in response to the voltage difference across the membrane, letting potassium ions pass in accordance with their electrochemical gradient. Homotetrameric channels mediate a delayed-rectifier voltage-dependent outward potassium current that display rapid activation and slow inactivation in response to membrane depolarization (PubMed:1550672). Can form functional homotetrameric and heterotetrameric channels that contain variable proportions of KCNB1; channel properties depend on the type of alpha subunits that are part of the channel (PubMed:20202934). Can also form functional heterotetrameric channels with other alpha subunits that are non-conducting when expressed alone, such as KCNS1 and KCNS2, creating a functionally diverse range of channel complexes (PubMed:9305895). In vivo, membranes probably contain a mixture of heteromeric potassium channel complexes, making it difficult to assign currents observed in intact tissues to any particular potassium channel family member. Contributes to the delayed-rectifier voltage-gated potassium current in cortical pyramidal neurons and smooth muscle cells (PubMed:1550672, PubMed:20202934).By similarity3 Publications
Activity regulationi
Inhibited by quinine at micromolar levels (By similarity). Modestly sensitive to millimolar levels of tetraethylammonium (TEA) (PubMed:1550672). Modestly sensitive to millimolar levels of 4-aminopyridine (4-AP).By similarity1 Publication1 Publication
Kineticsi
Homotetrameric channels expressed in xenopus oocytes or in mammalian non-neuronal cells display delayed-rectifier voltage-dependent potassium currents which are activated during membrane depolarization, i.e within a risetime of about 20 msec (PubMed:1550672). After that, inactivate very slowly (PubMed:1550672). Their activation requires low threshold potentials of about -20 to -30 mV, with a midpoint activation at about 10 mV. For inactivation, the voltage at half-maximal amplitude is about -30 mV. Channels have an unitary conductance of about 14 pS. The voltage-dependence of activation and inactivation and other channel characteristics vary depending on the experimental conditions, the expression system and post-translational modifications.1 Publication1 Publication
GO - Molecular functioni
- delayed rectifier potassium channel activity Source: UniProtKB
- ion channel binding Source: UniProtKB
- protein heterodimerization activity Source: UniProtKB
- voltage-gated potassium channel activity Source: GO_Central
GO - Biological processi
- potassium ion transmembrane transport Source: UniProtKB
- potassium ion transport Source: UniProtKB
- protein homooligomerization Source: InterPro
- protein localization to plasma membrane Source: UniProtKB
- regulation of ion transmembrane transport Source: UniProtKB-KW
Keywordsi
Molecular function | Ion channel, Potassium channel, Voltage-gated channel |
Biological process | Ion transport, Potassium transport, Transport |
Ligand | Potassium |
Names & Taxonomyi
Protein namesi | Recommended name: Potassium voltage-gated channel subfamily B member 2ImportedAlternative name(s): CDRK1 Publication Voltage-gated potassium channel subunit Kv2.2 |
Gene namesi | Name:Kcnb2Imported |
Organismi | Rattus norvegicus (Rat) |
Taxonomic identifieri | 10116 [NCBI] |
Taxonomic lineagei | Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Euarchontoglires › Glires › Rodentia › Myomorpha › Muroidea › Muridae › Murinae › Rattus |
Proteomesi |
|
Organism-specific databases
RGDi | 621349, Kcnb2 |
Subcellular locationi
Plasma membrane
- Cell membrane 4 Publications; Multi-pass membrane protein Curated
Other locations
- Perikaryon 2 Publications
- dendrite 2 Publications
Note: Localized uniformly throughout cell bodies and dendrites (PubMed:10719893). Colocalizes with KCNB1 to high-density somatodendritic clusters on cortical pyramidal neurons (PubMed:20202934).2 Publications
Plasma Membrane
- neuronal cell body membrane Source: UniProtKB
- plasma membrane Source: UniProtKB
- voltage-gated potassium channel complex Source: UniProtKB
Other locations
- dendrite Source: UniProtKB
- integral component of membrane Source: GO_Central
- neuronal cell body Source: RGD
- perikaryon Source: UniProtKB-SubCell
Topology
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Topological domaini | 1 – 190 | CytoplasmicBy similarityAdd BLAST | 190 | |
Transmembranei | 191 – 212 | Helical; Name=Segment S1By similarityAdd BLAST | 22 | |
Topological domaini | 213 – 232 | ExtracellularBy similarityAdd BLAST | 20 | |
Transmembranei | 233 – 254 | Helical; Name=Segment S2By similarityAdd BLAST | 22 | |
Topological domaini | 255 – 265 | CytoplasmicBy similarityAdd BLAST | 11 | |
Transmembranei | 266 – 284 | Helical; Name=Segment S3By similarityAdd BLAST | 19 | |
Topological domaini | 285 – 296 | ExtracellularBy similarityAdd BLAST | 12 | |
Transmembranei | 297 – 317 | Helical; Voltage-sensor; Name=Segment S4By similarityAdd BLAST | 21 | |
Topological domaini | 318 – 332 | CytoplasmicBy similarityAdd BLAST | 15 | |
Transmembranei | 333 – 355 | Helical; Name=Segment S5By similarityAdd BLAST | 23 | |
Topological domaini | 356 – 368 | ExtracellularBy similarityAdd BLAST | 13 | |
Intramembranei | 369 – 380 | Helical; Name=Pore helixBy similarityAdd BLAST | 12 | |
Intramembranei | 381 – 388 | By similarity | 8 | |
Topological domaini | 389 – 395 | ExtracellularBy similarity | 7 | |
Transmembranei | 396 – 424 | Helical; Name=Segment S6By similarityAdd BLAST | 29 | |
Topological domaini | 425 – 907 | CytoplasmicBy similarityAdd BLAST | 483 |
Keywords - Cellular componenti
Cell membrane, Cell projection, MembranePTM / Processingi
Molecule processing
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
ChainiPRO_0000054050 | 1 – 907 | Potassium voltage-gated channel subfamily B member 2Add BLAST | 907 |
Amino acid modifications
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Glycosylationi | 287 | N-linked (GlcNAc...) asparagineSequence analysis | 1 | |
Modified residuei | 448 | PhosphoserineCombined sources | 1 |
Post-translational modificationi
Phosphorylated (PubMed:20202934).1 Publication
Keywords - PTMi
Glycoprotein, PhosphoproteinProteomic databases
PaxDbi | Q63099 |
PRIDEi | Q63099 |
PTM databases
GlyGeni | Q63099, 1 site |
iPTMneti | Q63099 |
PhosphoSitePlusi | Q63099 |
Expressioni
Tissue specificityi
Expressed in pyramidal neurons of the cerebral cortex (at protein level) (PubMed:20202934). In the brain, the greatest density occurs in the olfactory bulb, followed by the cerebral cortex, hippocampus, and cerebellum. In peripheral tissues it is most prominent in whole tongue epithelium and circumvallate papillae (PubMed:1550672).2 Publications
Interactioni
Subunit structurei
GO - Molecular functioni
- ion channel binding Source: UniProtKB
- protein heterodimerization activity Source: UniProtKB
Protein-protein interaction databases
STRINGi | 10116.ENSRNOP00000050431 |
Structurei
Secondary structure
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details3D structure databases
SMRi | Q63099 |
ModBasei | Search... |
PDBe-KBi | Search... |
Family & Domainsi
Motif
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Motifi | 381 – 386 | Selectivity filterBy similarity | 6 |
Domaini
The transmembrane segment S4 functions as voltage-sensor and is characterized by a series of positively charged amino acids at every third position. Channel opening and closing is effected by a conformation change that affects the position and orientation of the voltage-sensor paddle formed by S3 and S4 within the membrane. A transmembrane electric field that is positive inside would push the positively charged S4 segment outwards, thereby opening the pore, while a field that is negative inside would pull the S4 segment inwards and close the pore. Changes in the position and orientation of S4 are then transmitted to the activation gate formed by the inner helix bundle via the S4-S5 linker region.By similarity
Sequence similaritiesi
Belongs to the potassium channel family. B (Shab) (TC 1.A.1.2) subfamily. Kv2.2/KCNB2 sub-subfamily. [View classification]Curated
Keywords - Domaini
Transmembrane, Transmembrane helixPhylogenomic databases
eggNOGi | KOG3713, Eukaryota |
InParanoidi | Q63099 |
PhylomeDBi | Q63099 |
Family and domain databases
Gene3Di | 1.20.120.350, 1 hit |
InterProi | View protein in InterPro IPR000210, BTB/POZ_dom IPR005821, Ion_trans_dom IPR003968, K_chnl_volt-dep_Kv IPR003973, K_chnl_volt-dep_Kv2 IPR005826, K_chnl_volt-dep_Kv2.2 IPR011333, SKP1/BTB/POZ_sf IPR003131, T1-type_BTB IPR028325, VG_K_chnl IPR027359, Volt_channel_dom_sf |
PANTHERi | PTHR11537, PTHR11537, 1 hit |
Pfami | View protein in Pfam PF02214, BTB_2, 1 hit PF00520, Ion_trans, 1 hit PF03521, Kv2channel, 1 hit |
PRINTSi | PR01515, KV22CHANNEL PR01491, KVCHANNEL PR01495, SHABCHANNEL |
SMARTi | View protein in SMART SM00225, BTB, 1 hit |
SUPFAMi | SSF54695, SSF54695, 1 hit |
i Sequence
Sequence statusi: Complete.
Q63099-1 [UniParc]FASTAAdd to basket
10 20 30 40 50
MAEKAPPGLN RKTSRSTLSL PPEPVDIIRS KTCSRRVKIN VGGLNHEVLW
60 70 80 90 100
RTLDRLPRTR LGKLRDCNTH ESLLEVCDDY NLNENEYFFD RHPGAFTSIL
110 120 130 140 150
NFYRTGKLHM MEEMCALSFG QELDYWGIDE IYLESCCQAR YHQKKEQMNE
160 170 180 190 200
ELRREAETMR DGEGEEFDNT CCPEKRKKLW DLLEKPNSSV AAKILAIVSI
210 220 230 240 250
LFIVLSTIAL SLNTLPELQE NDEFGQPSDN RKLAHVEAVC IAWFTMEYLL
260 270 280 290 300
RFLSSPNKWK FFKGPLNVID LLAILPYYVT IFLTESNKSV LQFQNVRRVV
310 320 330 340 350
QIFRIMRILR ILKLARHSTG LQSLGFTLRR SYNELGLLIL FLAMGIMIFS
360 370 380 390 400
SLVFFAEKDE DATKFTSIPA SFWWATITMT TVGYGDIYPK TLLGKIVGGL
410 420 430 440 450
CCIAGVLVIA LPIPIIVNNF SEFYKEQKRQ EKAIKRREAL ERAKRNGSIV
460 470 480 490 500
SMNLKDAFAR SMELIDVAVE KAGESANIKD SVDDNHLSPS RWKWARKALS
510 520 530 540 550
ETSSNKSYEN KYQEVSQKDS HEQLNNTSSS SPQHLSAQKL EMLYNEITKT
560 570 580 590 600
QTHSHPNPDC QEQPERPSAY EEEIEMEEVV CPQEQLAVAQ TEVIVDMKST
610 620 630 640 650
SSIDSFTSCA TDFTETERSP LPPPSASHLQ MKFPTDLPGM DEHQRVRAPP
660 670 680 690 700
FLTLSRDKGP AAREAALDYA PIDITVNLDA GASHGPLQPD SASDSPKSSL
710 720 730 740 750
KGSNPLKSRS LKVNFQENRG SAPQTPPSTA RPLPVTTADF PLTTPQHMST
760 770 780 790 800
ILLEESPPPG TETLPGADVS AHCQGPSKGL SPRVPKQKLF PFSSRERRSF
810 820 830 840 850
TEIDTGEDED FLDLQRPRPD KQADPSPNCL ADKPGEARDP LREEGCVGSS
860 870 880 890 900
SPQNTDHNCR QDIYQAVGEV KKDSSQEGYK MENHLFAPEI HSNPGDTGYC
PTRETSM
Sequence cautioni
The sequence AAA40905 differs from that shown. Reason: Frameshift.Curated
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | M77482 mRNA Translation: AAA40905.1 Frameshift. |
PIRi | JH0595 |
Genome annotation databases
UCSCi | RGD:621349, rat |
Similar proteinsi
Cross-referencesi
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | M77482 mRNA Translation: AAA40905.1 Frameshift. |
PIRi | JH0595 |
3D structure databases
Select the link destinations: PDBei RCSB PDBi PDBji Links Updated | PDB entry | Method | Resolution (Å) | Chain | Positions | PDBsum |
6EBK | electron microscopy | 3.30 | B/D/F/H | 278-311 | [»] | |
6EBL | electron microscopy | 3.00 | B/D/F/H | 278-311 | [»] | |
6EBM | electron microscopy | 4.00 | B/D/F/H | 278-311 | [»] | |
SMRi | Q63099 | |||||
ModBasei | Search... | |||||
PDBe-KBi | Search... |
Protein-protein interaction databases
STRINGi | 10116.ENSRNOP00000050431 |
Chemistry databases
GuidetoPHARMACOLOGYi | 547 |
PTM databases
GlyGeni | Q63099, 1 site |
iPTMneti | Q63099 |
PhosphoSitePlusi | Q63099 |
Proteomic databases
PaxDbi | Q63099 |
PRIDEi | Q63099 |
Protocols and materials databases
ABCDi | Q63099, 3 sequenced antibodies |
Genome annotation databases
UCSCi | RGD:621349, rat |
Organism-specific databases
RGDi | 621349, Kcnb2 |
Phylogenomic databases
eggNOGi | KOG3713, Eukaryota |
InParanoidi | Q63099 |
PhylomeDBi | Q63099 |
Miscellaneous databases
PROi | PR:Q63099 |
Family and domain databases
Gene3Di | 1.20.120.350, 1 hit |
InterProi | View protein in InterPro IPR000210, BTB/POZ_dom IPR005821, Ion_trans_dom IPR003968, K_chnl_volt-dep_Kv IPR003973, K_chnl_volt-dep_Kv2 IPR005826, K_chnl_volt-dep_Kv2.2 IPR011333, SKP1/BTB/POZ_sf IPR003131, T1-type_BTB IPR028325, VG_K_chnl IPR027359, Volt_channel_dom_sf |
PANTHERi | PTHR11537, PTHR11537, 1 hit |
Pfami | View protein in Pfam PF02214, BTB_2, 1 hit PF00520, Ion_trans, 1 hit PF03521, Kv2channel, 1 hit |
PRINTSi | PR01515, KV22CHANNEL PR01491, KVCHANNEL PR01495, SHABCHANNEL |
SMARTi | View protein in SMART SM00225, BTB, 1 hit |
SUPFAMi | SSF54695, SSF54695, 1 hit |
ProtoNeti | Search... |
MobiDBi | Search... |
Entry informationi
Entry namei | KCNB2_RAT | |
Accessioni | Q63099Primary (citable) accession number: Q63099 | |
Entry historyi | Integrated into UniProtKB/Swiss-Prot: | July 15, 1998 |
Last sequence update: | October 25, 2002 | |
Last modified: | December 2, 2020 | |
This is version 138 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
3D-structure, Reference proteomeDocuments
- PDB cross-references
Index of Protein Data Bank (PDB) cross-references - SIMILARITY comments
Index of protein domains and families