CASPR also known as Contactin associated protein 1, Paranodin and CASPR1 is a protein that in humans is encoded by the CNTNAP1 gene.[1]
CASPR is a part of the neurexin family of proteins, hence its another name "Neurexin IV".[2] 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.[3] During myelination, caspr associates with contactin in a cis complex,[3] though its precise role in myelination is not yet understood.
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].
↑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. PMID24319099.
Further reading
Martins-de-Souza D, Guest PC, Mann DM, Roeber S, Rahmoune H, Bauder C, Kretzschmar H, Volk B, Baborie A, Bahn S (April 2012). "Proteomic analysis identifies dysfunction in cellular transport, energy, and protein metabolism in different brain regions of atypical frontotemporal lobar degeneration". Journal of Proteome Research. 11 (4): 2533–43. doi:10.1021/pr2012279. PMID22360420.
Li R, Zhang B, Zheng Y (December 1997). "Structural determinants required for the interaction between Rho GTPase and the GTPase-activating domain of p190". The Journal of Biological Chemistry. 272 (52): 32830–5. doi:10.1074/jbc.272.52.32830. PMID9407060.
Lee JY, Park AK, Lee KM, Park SK, Han S, Han W, Noh DY, Yoo KY, Kim H, Chanock SJ, Rothman N, Kang D (September 2009). "Candidate gene approach evaluates association between innate immunity genes and breast cancer risk in Korean women". Carcinogenesis. 30 (9): 1528–31. doi:10.1093/carcin/bgp084. PMID19372141.
Venken K, Meuleman J, Irobi J, Ceuterick C, Martini R, De Jonghe P, Timmerman V (August 2001). "Caspr1/Paranodin/Neurexin IV is most likely not a common disease-causing gene for inherited peripheral neuropathies". NeuroReport. 12 (11): 2609–14. doi:10.1097/00001756-200108080-00063. PMID11496158.
Charles P, Tait S, Faivre-Sarrailh C, Barbin G, Gunn-Moore F, Denisenko-Nehrbass N, Guennoc AM, Girault JA, Brophy PJ, Lubetzki C (February 2002). "Neurofascin is a glial receptor for the paranodin/Caspr-contactin axonal complex at the axoglial junction". Current Biology. 12 (3): 217–20. doi:10.1016/S0960-9822(01)00680-7. PMID11839274.
