CASPR also known as Contactin associated protein 1, Paranodin and CASPR1 is a protein that in humans is encoded by the CNTNAP1 gene.[5] CASPR is a part of the neurexin family of proteins, hence its another name "Neurexin IV".[6] CASPR is a membrane protein found in the neuronal membrane in the paranodal section of the axon[[]] in myelinated neurons, between the Nodes of Ranvier containing Na+ channels, and juxtaparanode, which contains K+ channels.[7] During myelination, caspr associates with contactin in a cis complex,[7] though its precise role in myelination is not yet understood.

CNTNAP1
Identifiers
AliasesCNTNAP1, CASPR, CNTNAP, NRXN4, P190, contactin associated protein 1, CHN3
External IDsOMIM: 602346; MGI: 1858201; HomoloGene: 2693; GeneCards: CNTNAP1; OMA:CNTNAP1 - orthologs
Orthologs
SpeciesHumanMouse
Entrez
Ensembl
UniProt
RefSeq (mRNA)

NM_003632

NM_016782

RefSeq (protein)

NP_003623

NP_058062

Location (UCSC)Chr 17: 42.68 – 42.7 MbChr 11: 101.06 – 101.08 Mb
PubMed search[3][4]
Wikidata
View/Edit HumanView/Edit Mouse

Function

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The gene product was initially identified as a 190-kD protein associated with the contactin-PTPRZ1 complex. The 1,384-amino acid protein, also designated p190 or CASPR for 'contactin-associated protein,' includes an extracellular domain with several putative protein-protein interaction domains, a putative transmembrane domain, and a 74-amino acid cytoplasmic domain. Northern blot analysis showed that the gene is transcribed predominantly in brain as a transcript of 6.2 kb, with weak expression in several other tissues tested. The architecture of its extracellular domain is similar to that of neurexins, and this protein may be the signaling subunit of contactin, enabling recruitment and activation of intracellular signaling pathways in neurons. [provided by RefSeq, Jan 2009].

Clinical

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Mutations in CNTNAP1 cause arthrogryposis multiplex congenita.[8]

Other diseases associated with mutations in this gene include lethal congenital contracture syndrome type 7 and congenital hypomyelinating neuropathy type 3.[9]

References

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  1. ^ a b c GRCh38: Ensembl release 89: ENSG00000108797Ensembl, May 2017
  2. ^ a b c GRCm38: Ensembl release 89: ENSMUSG00000017167Ensembl, May 2017
  3. ^ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  4. ^ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  5. ^ "Entrez Gene: Contactin associated protein 1".
  6. ^ "OMIM Entry- * 602346 - CONTACTIN-ASSOCIATED PROTEIN 1; CNTNAP1". omim.org. Retrieved 2017-04-27.
  7. ^ a b Rios JC, Melendez-Vasquez CV, Einheber S, Lustig M, Grumet M, Hemperly J, et al. (15 November 2000). "Contactin-Associated Protein (Caspr) and Contactin Form a Complex That Is Targeted to the Paranodal Junctions during Myelination". J. Neurosci. 20 (22): 8354–8364. doi:10.1523/JNEUROSCI.20-22-08354.2000. PMC 6773165. PMID 11069942.
  8. ^ Laquérriere A, Maluenda J, Camus A, Fontenas L, Dieterich K, Nolent F, et al. (May 2014). "Mutations in CNTNAP1 and ADCY6 are responsible for severe arthrogryposis multiplex congenita with axoglial defects". Human Molecular Genetics. 23 (9): 2279–89. doi:10.1093/hmg/ddt618. PMID 24319099.
  9. ^ Sabbagh S, Antoun S, Mégarbané A (2020) CNTNAP1 Mutations and Their Clinical Presentations: New Case Report and Systematic Review. Case Rep Med 2020:8795607.

Further reading

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This article incorporates text from the United States National Library of Medicine, which is in the public domain.