Q96P56 · CTSR2_HUMAN

  • Protein
    Cation channel sperm-associated protein 2
  • Gene
    CATSPER2
  • Status
    UniProtKB reviewed (Swiss-Prot)
  • Amino acids
  • Protein existence
    Evidence at protein level
  • Annotation score
    5/5

Function

function

Pore-forming subunit of the CatSper complex, a sperm-specific voltage-gated calcium channel, that plays a central role in calcium-dependent physiological responses essential for successful fertilization, such as sperm hyperactivation, acrosome reaction and chemotaxis towards the oocyte.

Caution

In mouse, Slco6c1 is an additional auxiliary subunit of the CatSper complex. It is unclear if the related SLCO6A1 protein performs the same role in non-rodent species.

Catalytic activity

Activity regulation

The CatSper calcium channel is indirectly activated by extracellular progesterone and prostaglandins following the sequence: progesterone > PGF1-alpha = PGE1 > PGA1 > PGE2 >> PGD2 (PubMed:21412338, PubMed:21412339, PubMed:26989199).
The CatSper calcium channel is directly inhibited by endocannabinoid 2-arachidonoylglycerol (2AG) (PubMed:26989199).
Indirect activation by progesterone takes place via the following mechanism: progesterone binds and activates the acylglycerol lipase ABHD2, which in turn mediates hydrolysis of 2AG inhibitor, relieving inhibition of the CatSper channel (PubMed:26989199).
The primary effect of progesterone activation is to shift voltage dependence towards more physiological, negative membrane potentials; it is not mediated by metabotropic receptors and second messengers (PubMed:21412338, PubMed:21412339).
Sperm capacitation enhances the effect of progesterone by providing additional negative shift. Also activated by the elevation of intracellular pH (PubMed:21412338, PubMed:21412339).

GO annotations

AspectTerm
Cellular ComponentCatSper complex
Cellular Componentmotile cilium
Cellular Componentplasma membrane
Molecular Functioncalcium-activated cation channel activity
Molecular Functionvoltage-gated calcium channel activity
Biological Processcalcium ion transport
Biological Processfertilization
Biological Processflagellated sperm motility
Biological Processsperm capacitation

Keywords

Enzyme and pathway databases

Protein family/group databases

Names & Taxonomy

Protein names

  • Recommended name
    Cation channel sperm-associated protein 2
  • Short names
    CatSper2

Gene names

    • Name
      CATSPER2

Organism names

  • Taxonomic identifier
  • Taxonomic lineage
    Eukaryota > Metazoa > Chordata > Craniata > Vertebrata > Euteleostomi > Mammalia > Eutheria > Euarchontoglires > Primates > Haplorrhini > Catarrhini > Hominidae > Homo

Accessions

  • Primary accession
    Q96P56
  • Secondary accessions
    • Q8NHT9
    • Q96P54
    • Q96P55

Proteomes

Organism-specific databases

Subcellular Location

Features

Showing features for topological domain, transmembrane, intramembrane.

TypeIDPosition(s)Description
Topological domain1-108Cytoplasmic
Transmembrane109-131Helical; Name=Segment S1
Topological domain132-140Extracellular
Transmembrane141-166Helical; Name=Segment S2
Topological domain167-175Cytoplasmic
Transmembrane176-200Helical; Name=Segment S3
Topological domain201-203Extracellular
Transmembrane204-222Helical; Name=Segment S4
Topological domain223-239Cytoplasmic
Transmembrane240-262Helical; Name=Segment S5
Topological domain263-281Extracellular
Intramembrane282-294Helical; Pore-forming
Topological domain295-314Extracellular
Transmembrane315-341Helical; Name=Segment S6
Topological domain342-530Cytoplasmic

Keywords

Disease & Variants

Involvement in disease

Deafness-infertility syndrome (DIS)

  • Note
    • The disease is caused by variants affecting the gene represented in this entry
  • Description
    Characterized by deafness and infertility and is caused by large contiguous gene deletions at 15q15.3 that removes both STRC and CATSPER2 genes.
  • See also
    MIM:611102

Features

Showing features for natural variant.

TypeIDPosition(s)Description
Natural variantVAR_0333078in dbSNP:rs2614835
Natural variantVAR_03330857in dbSNP:rs8042868

Variants

We now provide the "Disease & Variants" viewer in its own tab.

The viewer provides 688 variants from UniProt as well as other sources including ClinVar and dbSNP.

Go to variant viewer

Organism-specific databases

Miscellaneous

Chemistry

Genetic variation databases

PTM/Processing

Features

Showing features for chain.

TypeIDPosition(s)Description
ChainPRO_00002956761-530Cation channel sperm-associated protein 2

Proteomic databases

PTM databases

Expression

Tissue specificity

Testis-specific.

Gene expression databases

Organism-specific databases

Interaction

Subunit

Component of the CatSper complex or CatSpermasome composed of the core pore-forming members CATSPER1, CATSPER2, CATSPER3 and CATSPER4 as well as auxiliary members CATSPERB, CATSPERG, CATSPERD, CATSPERE, CATSPERZ, C2CD6/CATSPERT, TMEM249, TMEM262 and EFCAB9 (By similarity).
HSPA1 may be an additional auxiliary complex member (By similarity).
The core complex members CATSPER1, CATSPER2, CATSPER3 and CATSPER4 form a heterotetrameric channel (By similarity).
The auxiliary CATSPERB, CATSPERG, CATSPERD and CATSPERE subunits form a pavilion-like structure over the pore which stabilizes the complex through interactions with CATSPER4, CATSPER3, CATSPER1 and CATSPER2 respectively (By similarity).
TMEM262/CATSPERH interacts with CATSPERB, further stabilizing the complex. C2CD6/CATSPERT interacts at least with CATSPERD and is required for targeting the CatSper complex in the flagellar membrane (By similarity).
Interacts with Ca(v)3.3/CACNA1I, leading to suppression of T-type calcium channel activity (PubMed:16740636).

Binary interactions

TypeEntry 1Entry 2Number of experimentsIntact
BINARY Q96P56CACNA1I Q9P0X43EBI-2215024, EBI-1220829

Protein-protein interaction databases

Miscellaneous

Structure

Family & Domains

Features

Showing features for compositional bias, region.

TypeIDPosition(s)Description
Compositional bias378-398Basic and acidic residues
Region378-458Disordered
Compositional bias399-424Polar residues
Compositional bias439-458Polar residues

Sequence similarities

Keywords

Phylogenomic databases

Family and domain databases

Sequence & Isoforms

Align isoforms (4)
  • Sequence status
    Complete

This entry describes 4 isoforms produced by Alternative splicing.

Q96P56-1

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.

  • Name
    1
  • Synonyms
    Variant 2
  • See also
    sequence in UniParc or sequence clusters in UniRef
  • Length
    530
  • Mass (Da)
    62,041
  • Last updated
    2007-07-24 v2
  • Checksum
    8561CC0E9F3590B0
MAAYQQEEQMQLPRADAIRSRLIDTFSLIEHLQGLSQAVPRHTIRELLDPSRQKKLVLGDQHQLVRFSIKPQRIEQISHAQRLLSRLHVRCSQRPPLSLWAGWVLECPLFKNFIIFLVFLNTIILMVEIELLESTNTKLWPLKLTLEVAAWFILLIFILEILLKWLSNFSVFWKSAWNVFDFVVTMLSLLPEVVVLVGVTGQSVWLQLLRICRVLRSLKLLAQFRQIQIIILVLVRALKSMTFLLMLLLIFFYIFAVTGVYVFSEYTRSPRQDLEYHVFFSDLPNSLVTVFILFTLDHWYALLQDVWKVPEVSRIFSSIYFILWLLLGSIIFRSIIVAMMVTNFQNIRKELNEEMARREVQLKADMFKRQIIQRRKNMSHEALTSSHSKIEDSSRGASQQRESLDLSEVSEVESNYGATEEDLITSASKTEETLSKKREYQSSSCVSSTSSSYSSSSESRFSESIGRLDWETLVHENLPGLMEMDQDDRVWPRDSLFRYFELLEKLQYNLEERKKLQEFAVQALMNLEDK

Q96P56-2

  • Name
    2
  • Synonyms
    Variant 1
  • See also
    sequence in UniParc or sequence clusters in UniRef
  • Differences from canonical

Q96P56-3

  • Name
    3
  • Synonyms
    Variant 3
  • See also
    sequence in UniParc or sequence clusters in UniRef
  • Differences from canonical
    • 393-414: SSRGASQQRESLDLSEVSEVES → RSFGLGDSCARKSARANGNGSG
    • 415-530: Missing

Q96P56-4

  • Name
    4
  • See also
    sequence in UniParc or sequence clusters in UniRef
  • Differences from canonical

Computationally mapped potential isoform sequences

There are 5 potential isoforms mapped to this entry

View all
EntryEntry nameGene nameLength
E7EX46E7EX46_HUMANCATSPER279
F8W9H2F8W9H2_HUMANCATSPER2534
H7BZ89H7BZ89_HUMANCATSPER274
B8ZZQ9B8ZZQ9_HUMANCATSPER264
H7C2X6H7C2X6_HUMANCATSPER213

Features

Showing features for sequence conflict, alternative sequence, compositional bias.

TypeIDPosition(s)Description
Sequence conflict46in Ref. 2; AAH28728
Alternative sequenceVSP_026973188-199in isoform 4
Alternative sequenceVSP_026974200-530in isoform 4
Compositional bias378-398Basic and acidic residues
Alternative sequenceVSP_026976393-394in isoform 2
Alternative sequenceVSP_026975393-414in isoform 3
Compositional bias399-424Polar residues
Alternative sequenceVSP_026977415-530in isoform 3
Compositional bias439-458Polar residues

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
AF411817
EMBL· GenBank· DDBJ
AAL26490.1
EMBL· GenBank· DDBJ
mRNA
AF411818
EMBL· GenBank· DDBJ
AAL26491.1
EMBL· GenBank· DDBJ
mRNA
AF411819
EMBL· GenBank· DDBJ
AAL26492.1
EMBL· GenBank· DDBJ
mRNA
BC028728
EMBL· GenBank· DDBJ
AAH28728.1
EMBL· GenBank· DDBJ
mRNA
BC064387
EMBL· GenBank· DDBJ
AAH64387.1
EMBL· GenBank· DDBJ
mRNA

Genome annotation databases

Similar Proteins

Disclaimer

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