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1.A.1.15.2
    6 TMS voltage-gated K channel, KCNQ2 or Kv7.2.  Mutations cause benign familial neonatal convulsions (BNFC; epilepsy; Maljevic et al. 2016).  It forms homotetramers or heterotetramers with KCNQ3/Kv7.3) (Soldovieri et al., 2006; Uehara et al., 2008)). Like all other Kv7.2 channels, it is activated by phosphatidyl inositol-4,5-bisphosphate and hence can be regulated by various neurotransmitters and hormones (Telezhkin et al. 2013).  Gating pore currents that go through the gating pores in TMSs1-4 (the voltage sensor) may give rise to peripheral nerve hyperexcitability (Moreau et al. 2014). Retigabine and ICA73, two anti-epileptic drugs, act via distinct mechanisms due to interactions with specific residues that underlie subtype specificity of KCNQ channel openers (Wang et al. 2016).

Accession Number:O43526
Protein Name:KCNQ2
Length:872
Molecular Weight:95848.00
Species:Homo sapiens (Human) [9606]
Number of TMSs:6
Location1 / Topology2 / Orientation3: Membrane1 / Multi-pass membrane protein2
Substrate K+

Cross database links:

Genevestigator: O43526
eggNOG: prNOG17209
RefSeq: NP_004509.2    NP_742104.1    NP_742105.1    NP_742106.1    NP_742107.1   
Entrez Gene ID: 3785   
Pfam: PF00520    PF03520    PF11956   
Drugbank: Drugbank Link   
OMIM: 121200  phenotype
602235  gene
KEGG: hsa:3785   

Gene Ontology

GO:0008076 C:voltage-gated potassium channel complex
GO:0005249 F:voltage-gated potassium channel activity
GO:0007399 P:nervous system development
GO:0006813 P:potassium ion transport
GO:0007268 P:synaptic transmission
GO:0055085 P:transmembrane transport

References (27)

[1] “Identification and cloning of neuroblastoma-specific and nerve tissue-specific genes through compiled expression profiles.”  Yokoyama M.et.al.   9039501
[2] “A novel potassium channel gene, KCNQ2, is mutated in an inherited epilepsy of newborns.”  Singh N.A.et.al.   9425895
[3] “A potassium channel mutation in neonatal human epilepsy.”  Biervert C.et.al.   9430594
[4] “KCNQ2 and KCNQ3 potassium channel subunits: molecular correlates of the M-channel.”  Wang H.-S.et.al.   9836639
[5] “The KCNQ2 potassium channel: splice variants, functional and developmental expression. Brain localization and comparison with KCNQ3.”  Tinel N.et.al.   9827540
[6] “Functional expression of two KvLQT1-related potassium channels responsible for an inherited idiopathic epilepsy.”  Yang W.-P.et.al.   9677360
[7] “Differential expression of KCNQ2 splice variants: implications to M current function during neuronal development.”  Smith J.S.et.al.   11160379
[8] “The DNA sequence and comparative analysis of human chromosome 20.”  Deloukas P.et.al.   11780052
[9] “The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC).”  The MGC Project Teamet.al.   15489334
[10] “Moderate loss of function of cyclic-AMP-modulated KCNQ2/KCNQ3 K+ channels causes epilepsy.”  Schroeder B.C.et.al.   9872318
[11] “Two types of K(+) channel subunit, Erg1 and KCNQ2/3, contribute to the M-like current in a mammalian neuronal cell.”  Selyanko A.A.et.al.   10479678
[12] “M-type KCNQ2-KCNQ3 potassium channels are modulated by the KCNE2 subunit.”  Tinel N.et.al.   11034315
[13] “Surface expression and single channel properties of KCNQ2/KCNQ3, M-type K+ channels involved in epilepsy.”  Schwake M.et.al.   10788442
[14] “Reconstitution of muscarinic modulation of the KCNQ2/KCNQ3 K(+) channels that underlie the neuronal M current.”  Shapiro M.S.et.al.   10684873
[15] “Inhibition of KCNQ1-4 potassium channels expressed in mammalian cells via M1 muscarinic acetylcholine receptors.”  Selyanko A.A.et.al.   10713961
[16] “Modulation of KCNQ2/3 potassium channels by the novel anticonvulsant retigabine.”  Main M.J.et.al.   10908292
[17] “Retigabine, a novel anti-convulsant, enhances activation of KCNQ2/Q3 potassium channels.”  Wickenden A.D.et.al.   10953053
[18] “The novel anticonvulsant retigabine activates M-currents in Chinese hamster ovary-cells tranfected with human KCNQ2/3 subunits.”  Rundfeldt C.et.al.   10713399
[19] “Colocalization and coassembly of two human brain M-type potassium channel subunits that are mutated in epilepsy.”  Cooper E.C.et.al.   10781098
[20] “An unappreciated role for RNA surveillance.”  Hillman R.T.et.al.   14759258
[21] “Structural and mutational analysis of KCNQ2, the major gene locus for benign familial neonatal convulsions.”  Biervert C.et.al.   10323247
[22] “Benign familial neonatal convulsions (BFNC) resulting from mutation of the KCNQ2 voltage sensor.”  Miraglia del Giudice E.et.al.   11175290
[23] “Myokymia and neonatal epilepsy caused by a mutation in the voltage sensor of the KCNQ2 K+ channel.”  Dedek K.et.al.   11572947
[24] “KCNQ2 and KCNQ3 potassium channel genes in benign familial neonatal convulsions: expansion of the functional and mutation spectrum.”  Singh N.A.et.al.   14534157
[25] “Neonatal convulsions and epileptic encephalopathy in an Italian family with a missense mutation in the fifth transmembrane region of KCNQ2.”  Dedek K.et.al.   12742592
[26] “Peripheral nerve hyperexcitability due to dominant-negative KCNQ2 mutations.”  Wuttke T.V.et.al.   17872363
[27] “A novel mutation in KCNQ2 associated with BFNC, drug resistant epilepsy, and mental retardation.”  Borgatti R.et.al.   15249611

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FASTA formatted sequence
1:	MVQKSRNGGV YPGPSGEKKL KVGFVGLDPG APDSTRDGAL LIAGSEAPKR GSILSKPRAG 
61:	GAGAGKPPKR NAFYRKLQNF LYNVLERPRG WAFIYHAYVF LLVFSCLVLS VFSTIKEYEK 
121:	SSEGALYILE IVTIVVFGVE YFVRIWAAGC CCRYRGWRGR LKFARKPFCV IDIMVLIASI 
181:	AVLAAGSQGN VFATSALRSL RFLQILRMIR MDRRGGTWKL LGSVVYAHSK ELVTAWYIGF 
241:	LCLILASFLV YLAEKGENDH FDTYADALWW GLITLTTIGY GDKYPQTWNG RLLAATFTLI 
301:	GVSFFALPAG ILGSGFALKV QEQHRQKHFE KRRNPAAGLI QSAWRFYATN LSRTDLHSTW 
361:	QYYERTVTVP MYSSQTQTYG ASRLIPPLNQ LELLRNLKSK SGLAFRKDPP PEPSPSKGSP 
421:	CRGPLCGCCP GRSSQKVSLK DRVFSSPRGV AAKGKGSPQA QTVRRSPSAD QSLEDSPSKV 
481:	PKSWSFGDRS RARQAFRIKG AASRQNSEEA SLPGEDIVDD KSCPCEFVTE DLTPGLKVSI 
541:	RAVCVMRFLV SKRKFKESLR PYDVMDVIEQ YSAGHLDMLS RIKSLQSRVD QIVGRGPAIT 
601:	DKDRTKGPAE AELPEDPSMM GRLGKVEKQV LSMEKKLDFL VNIYMQRMGI PPTETEAYFG 
661:	AKEPEPAPPY HSPEDSREHV DRHGCIVKIV RSSSSTGQKN FSAPPAAPPV QCPPSTSWQP 
721:	QSHPRQGHGT SPVGDHGSLV RIPPPPAHER SLSAYGGGNR ASMEFLRQED TPGCRPPEGN 
781:	LRDSDTSISI PSVDHEELER SFSGFSISQS KENLDALNSC YAAVAPCAKV RPYIAEGESD 
841:	TDSDLCTPCG PPPRSATGEG PFGDVGWAGP RK