Q9H2S1 (KCNN2_HUMAN) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Small conductance calcium-activated potassium channel protein 2
Short name=SK2
Short name=SKCa 2
Short name=SKCa2

Alternative name(s):
KCa2.2

Gene names

Name:

KCNN2

Organism

Homo sapiens (Human) [Reference proteome]

Taxonomic identifier

9606 [NCBI]

Taxonomic lineage

cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Deuterostomia › Chordata › Craniata › Vertebrata › Gnathostomata › Teleostomi › Euteleostomi › Sarcopterygii › Tetrapoda › Amniota › Mammalia › Theria › Eutheria › Euarchontoglires › Primates › Haplorrhini › Simiiformes › Catarrhini › Hominoidea › Hominidae › Homininae › Homo

Protein attributes

Sequence length	579 AA.
Sequence status	Complete.
Protein existence	Evidence at transcript level

General annotation (Comments)

Function	Forms a voltage-independent potassium channel activated by intracellular calcium. Activation is followed by membrane hyperpolarization. Thought to regulate neuronal excitability by contributing to the slow component of synaptic afterhyperpolarization. The channel is blocked by apamin.
Subunit structure	Heterooligomer. The complex is composed of 4 channel subunits each of which binds to a calmodulin subunit which regulates the channel activity through calcium-binding By similarity.
Subcellular location	Membrane; Multi-pass membrane protein.
Tissue specificity	Widely expressed.
Sequence similarities	Belongs to the potassium channel KCNN family. KCa2.2/KCNN2 subfamily.

Ontologies

Keywords
Biological process	Ion transport Transport
Cellular component	Membrane
Coding sequence diversity	Alternative splicing
Domain	Transmembrane Transmembrane helix
Ligand	Calmodulin-binding
Molecular function	Ion channel
Technical term	Complete proteome Reference proteome
Gene Ontology (GO)
Biological_process	regulation of potassium ion transmembrane transport Inferred from direct assay PubMed 17110593. Source: BHF-UCL synaptic transmission Traceable author statement. Source: Reactome
Cellular_component	T-tubule Inferred from electronic annotation. Source: Compara Z disc Inferred from electronic annotation. Source: Compara integral to membrane Non-traceable author statement Ref.1. Source: UniProtKB plasma membrane Traceable author statement. Source: Reactome
Molecular_function	small conductance calcium-activated potassium channel activity Traceable author statement Ref.1. Source: UniProtKB
Complete GO annotation...

Alternative products

This entry describes 2 isoforms produced by alternative splicing. [Align] [Select]

Isoform 1 (identifier: Q9H2S1-1)

This isoform has been chosen as the 'canonical' sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.

Isoform 2 (identifier: Q9H2S1-2)

The sequence of this isoform differs from the canonical sequence as follows:
     1-348: Missing.

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 579	579	Small conductance calcium-activated potassium channel protein 2		PRO_0000155010
Regions
	Transmembrane	138 – 158	21	Helical; Name=Segment S1; Potential
	Transmembrane	168 – 188	21	Helical; Name=Segment S2; Potential
	Transmembrane	214 – 234	21	Helical; Name=Segment S3; Potential
	Transmembrane	256 – 276	21	Helical; Name=Segment S4; Potential
	Transmembrane	305 – 325	21	Helical; Name=Segment S5; Potential
	Intramembrane	345 – 365	21	Pore-forming; Name=Segment H5; Potential
	Transmembrane	374 – 394	21	Helical; Name=Segment S6; Potential
	Region	412 – 488	77	Calmodulin-binding By similarity
	Compositional bias	41 – 45	5	Poly-Gly
	Compositional bias	51 – 58	8	Poly-Ala
	Compositional bias	83 – 88	6	Poly-Gly
	Compositional bias	91 – 102	12	Poly-Gly
	Compositional bias	563 – 566	4	Poly-Arg
Natural variations
	Alternative sequence	1 – 348	348	Missing in isoform 2.		VSP_044584
Experimental info
	Sequence conflict	50	1	S → SA in AAK84039. Ref.2
	Sequence conflict	52	1	A → D in AAG16728. Ref.1
	Sequence conflict	323	1	I → T in AAK84039. Ref.2
	Sequence conflict	530	1	Q → R in AAK84039. Ref.2

Sequences

	Sequence		Length	Mass (Da)
	Isoform 1 [UniParc]. Last modified October 14, 2008. Version 2. Checksum: 2ED87FE13C106183	FASTA	579	63,760
	10 20 30 40 50 60 MSSCRYNGGV MRPLSNLSAS RRNLHEMDSE AQPLQPPASV GGGGGASSPS AAAAAAAAVS 70 80 90 100 110 120 SSAPEIVVSK PEHNNSNNLA LYGTGGGGST GGGGGGGGSG HGSSSGTKSS KKKNQNIGYK 130 140 150 160 170 180 LGHRRALFEK RKRLSDYALI FGMFGIVVMV IETELSWGAY DKASLYSLAL KCLISLSTII 190 200 210 220 230 240 LLGLIIVYHA REIQLFMVDN GADDWRIAMT YERIFFICLE ILVCAIHPIP GNYTFTWTAR 250 260 270 280 290 300 LAFSYAPSTT TADVDIILSI PMFLRLYLIA RVMLLHSKLF TDASSRSIGA LNKINFNTRF 310 320 330 340 350 360 VMKTLMTICP GTVLLVFSIS LWIIAAWTVR ACERYHDQQD VTSNFLGAMW LISITFLSIG 370 380 390 400 410 420 YGDMVPNTYC GKGVCLLTGI MGAGCTALVV AVVARKLELT KAEKHVHNFM MDTQLTKRVK 430 440 450 460 470 480 NAAANVLRET WLIYKNTKLV KKIDHAKVRK HQRKFLQAIH QLRSVKMEQR KLNDQANTLV 490 500 510 520 530 540 DLAKTQNIMY DMISDLNERS EDFEKRIVTL ETKLETLIGS IHALPGLISQ TIRQQQRDFI 550 560 570 EAQMESYDKH VTYNAERSRS SSRRRRSSST APPTSSESS
	Isoform 2 [UniParc]. Checksum: 89BD2ED1EAD6E54B	FASTA	231	26,341
	10 20 30 40 50 60 MWLISITFLS IGYGDMVPNT YCGKGVCLLT GIMGAGCTAL VVAVVARKLE LTKAEKHVHN 70 80 90 100 110 120 FMMDTQLTKR VKNAAANVLR ETWLIYKNTK LVKKIDHAKV RKHQRKFLQA IHQLRSVKME 130 140 150 160 170 180 QRKLNDQANT LVDLAKTQNI MYDMISDLNE RSEDFEKRIV TLETKLETLI GSIHALPGLI 190 200 210 220 230 SQTIRQQQRD FIEAQMESYD KHVTYNAERS RSSSRRRRSS STAPPTSSES S

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Ca2+-activated K+ channels in human leukemic Jurkat T cells. Molecular cloning, biochemical and functional characterization." Desai R., Peretz A., Idelson H., Lazarovici P., Attali B. J. Biol. Chem. 275:39954-39963(2000) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
[2]	"Characterization of calcium-activated potassium channels in human myometrium." Mazzone J.N., Kaiser R.A., Buxton I.L.O. Submitted (JUL-2001) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1). Tissue: Myometrium.
[3]	"Complete sequencing and characterization of 21,243 full-length human cDNAs." Ota T., Suzuki Y., Nishikawa T., Otsuki T., Sugiyama T., Irie R., Wakamatsu A., Hayashi K., Sato H., Nagai K., Kimura K., Makita H., Sekine M., Obayashi M., Nishi T., Shibahara T., Tanaka T., Ishii S. , Yamamoto J., Saito K., Kawai Y., Isono Y., Nakamura Y., Nagahari K., Murakami K., Yasuda T., Iwayanagi T., Wagatsuma M., Shiratori A., Sudo H., Hosoiri T., Kaku Y., Kodaira H., Kondo H., Sugawara M., Takahashi M., Kanda K., Yokoi T., Furuya T., Kikkawa E., Omura Y., Abe K., Kamihara K., Katsuta N., Sato K., Tanikawa M., Yamazaki M., Ninomiya K., Ishibashi T., Yamashita H., Murakawa K., Fujimori K., Tanai H., Kimata M., Watanabe M., Hiraoka S., Chiba Y., Ishida S., Ono Y., Takiguchi S., Watanabe S., Yosida M., Hotuta T., Kusano J., Kanehori K., Takahashi-Fujii A., Hara H., Tanase T.-O., Nomura Y., Togiya S., Komai F., Hara R., Takeuchi K., Arita M., Imose N., Musashino K., Yuuki H., Oshima A., Sasaki N., Aotsuka S., Yoshikawa Y., Matsunawa H., Ichihara T., Shiohata N., Sano S., Moriya S., Momiyama H., Satoh N., Takami S., Terashima Y., Suzuki O., Nakagawa S., Senoh A., Mizoguchi H., Goto Y., Shimizu F., Wakebe H., Hishigaki H., Watanabe T., Sugiyama A., Takemoto M., Kawakami B., Yamazaki M., Watanabe K., Kumagai A., Itakura S., Fukuzumi Y., Fujimori Y., Komiyama M., Tashiro H., Tanigami A., Fujiwara T., Ono T., Yamada K., Fujii Y., Ozaki K., Hirao M., Ohmori Y., Kawabata A., Hikiji T., Kobatake N., Inagaki H., Ikema Y., Okamoto S., Okitani R., Kawakami T., Noguchi S., Itoh T., Shigeta K., Senba T., Matsumura K., Nakajima Y., Mizuno T., Morinaga M., Sasaki M., Togashi T., Oyama M., Hata H., Watanabe M., Komatsu T., Mizushima-Sugano J., Satoh T., Shirai Y., Takahashi Y., Nakagawa K., Okumura K., Nagase T., Nomura N., Kikuchi H., Masuho Y., Yamashita R., Nakai K., Yada T., Nakamura Y., Ohara O., Isogai T., Sugano S. Nat. Genet. 36:40-45(2004) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1). Tissue: Hippocampus.
[4]	"The DNA sequence and comparative analysis of human chromosome 5." Schmutz J., Martin J., Terry A., Couronne O., Grimwood J., Lowry S., Gordon L.A., Scott D., Xie G., Huang W., Hellsten U., Tran-Gyamfi M., She X., Prabhakar S., Aerts A., Altherr M., Bajorek E., Black S. , Branscomb E., Caoile C., Challacombe J.F., Chan Y.M., Denys M., Detter J.C., Escobar J., Flowers D., Fotopulos D., Glavina T., Gomez M., Gonzales E., Goodstein D., Grigoriev I., Groza M., Hammon N., Hawkins T., Haydu L., Israni S., Jett J., Kadner K., Kimball H., Kobayashi A., Lopez F., Lou Y., Martinez D., Medina C., Morgan J., Nandkeshwar R., Noonan J.P., Pitluck S., Pollard M., Predki P., Priest J., Ramirez L., Retterer J., Rodriguez A., Rogers S., Salamov A., Salazar A., Thayer N., Tice H., Tsai M., Ustaszewska A., Vo N., Wheeler J., Wu K., Yang J., Dickson M., Cheng J.-F., Eichler E.E., Olsen A., Pennacchio L.A., Rokhsar D.S., Richardson P., Lucas S.M., Myers R.M., Rubin E.M. Nature 431:268-274(2004) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[5]	Mural R.J., Istrail S., Sutton G.G., Florea L., Halpern A.L., Mobarry C.M., Lippert R., Walenz B., Shatkay H., Dew I., Miller J.R., Flanigan M.J., Edwards N.J., Bolanos R., Fasulo D., Halldorsson B.V., Hannenhalli S., Turner R. , Yooseph S., Lu F., Nusskern D.R., Shue B.C., Zheng X.H., Zhong F., Delcher A.L., Huson D.H., Kravitz S.A., Mouchard L., Reinert K., Remington K.A., Clark A.G., Waterman M.S., Eichler E.E., Adams M.D., Hunkapiller M.W., Myers E.W., Venter J.C. Submitted (SEP-2005) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[6]	"The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)." The MGC Project Team Genome Res. 14:2121-2127(2004) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORMS 1 AND 2). Tissue: Brain and Skin.
+	Additional computationally mapped references.

Cross-references

Sequence databases
EMBL GenBank DDBJ	AF239613 mRNA. Translation: AAG16728.1. AF397175 mRNA. Translation: AAK84039.1. AK289948 mRNA. Translation: BAF82637.1. AC025761 Genomic DNA. No translation available. AC109482 Genomic DNA. No translation available. CH471086 Genomic DNA. Translation: EAW48975.1. CH471086 Genomic DNA. Translation: EAW48976.1. BC015371 mRNA. Translation: AAH15371.1. BC117454 mRNA. Translation: AAI17455.1. BC117456 mRNA. Translation: AAI17457.1.
IPI	IPI00301072. IPI00377145.
RefSeq	NP_067627.2. NM_021614.2. NP_740721.1. NM_170775.1.
UniGene	Hs.98280.
3D structure databases
ProteinModelPortal	Q9H2S1.
ModBase	Search...
Protein-protein interaction databases
DIP	DIP-48997N.
STRING	9606.ENSP00000264773.
Protein family/group databases
TCDB	1.A.1.16.1. voltage-gated ion channel (VIC) superfamily.
PTM databases
PhosphoSite	Q9H2S1.
Polymorphism databases
DMDM	209572638.
Proteomic databases
PaxDb	Q9H2S1.
PRIDE	Q9H2S1.
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Genome annotation databases
Ensembl	ENST00000264773; ENSP00000264773; ENSG00000080709. ENST00000503706; ENSP00000421439; ENSG00000080709.
GeneID	3781.
KEGG	hsa:3781.
UCSC	uc003kqo.3. human.
Organism-specific databases
CTD	3781.
GeneCards	GC05P113725.
HGNC	HGNC:6291. KCNN2.
HPA	HPA038221.
MIM	605879. gene.
neXtProt	NX_Q9H2S1.
PharmGKB	PA30071.
GenAtlas	Search...
Phylogenomic databases
eggNOG	NOG320393.
HOVERGEN	HBG052241.
InParanoid	Q9H2S1.
KO	K04943.
OMA	AQMESYD.
OrthoDB	EOG49CQ7G.
PhylomeDB	Q9H2S1.
Enzyme and pathway databases
Reactome	REACT_13685. Neuronal System.
Gene expression databases
ArrayExpress	Q9H2S1.
Bgee	Q9H2S1.
CleanEx	HS_KCNN2.
Genevestigator	Q9H2S1.
GermOnline	ENSG00000080709. Homo sapiens.
Family and domain databases
InterPro	IPR004178. CaM-bd_dom. IPR013099. Ion_trans_2. IPR015449. K_chnl_Ca-activ_SK. [Graphical view]
PANTHER	PTHR10153. PTHR10153. 1 hit.
Pfam	PF02888. CaMBD. 1 hit. PF07885. Ion_trans_2. 1 hit. PF03530. SK_channel. 1 hit. [Graphical view]
PRINTS	PR01451. SKCHANNEL.
SMART	SM01053. CaMBD. 1 hit. [Graphical view]
SUPFAM	SSF81327. CaM_bd. 1 hit.
ProtoNet	Search...
Other
BindingDB	Q9H2S1.
ChEMBL	CHEMBL4469.
GenomeRNAi	3781.
NextBio	14837.
SOURCE	Search...

Entry information

Entry name

KCNN2_HUMAN

Accession

Primary (citable) accession number: Q9H2S1
Secondary accession number(s): A6NF94, Q0VFZ4, Q6PJI0

Entry history

Integrated into UniProtKB/Swiss-Prot:	November 16, 2001
Last sequence update:	October 14, 2008
Last modified:	May 1, 2013
This is version 105 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Chordata Protein Annotation Program

Disclaimer

Any medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.