Calpain small subunit 1 (CSS1) is a protein that in humans is encoded by the CAPNS1gene.[1][2][3]
Function
Calpains are a ubiquitous, well-conserved family of calcium-dependent, cysteine proteases. Calpain families have been implicated in neurodegenerative processes, as their activation can be triggered by calcium influx and oxidative stress. Calpain I and II are heterodimeric with distinct large subunits associated with common small subunits, all of which are encoded by different genes. The small regulatory subunit consists of an N-terminal domain, containing about 30% glycine residues and a C-terminal Ca-binding domain.[4] Two transcript variants encoding the same protein have been identified for this gene.[3]
Functions
Myotonic dystrophy
This gene encodes a small subunit common to both calpain I and II and is associated with myotonic dystrophy.[3]
Biomarker
'Elevated expression of CAPNS1 has been found to be associated with progression of various cancers such as hepatocellular and renal carcinoma.
[5]
^Lin GD, Chattopadhyay D, Maki M, Wang KK, Carson M, Jin L, Yuen PW, Takano E, Hatanaka M, DeLucas LJ, Narayana SV (July 1997). "Crystal structure of calcium bound domain VI of calpain at 1.9 A resolution and its role in enzyme assembly, regulation, and inhibitor binding". Nature Structural Biology. 4 (7): 539–47. doi:10.1038/nsb0797-539. PMID9228946. S2CID31913560.
Reverter D, Sorimachi H, Bode W (August 2001). "The structure of calcium-free human m-calpain: implications for calcium activation and function". Trends in Cardiovascular Medicine. 11 (6): 222–9. doi:10.1016/S1050-1738(01)00112-8. PMID11673052.
Banik NL, DeVries GH, Neuberger T, Russell T, Chakrabarti AK, Hogan EL (July 1991). "Calcium-activated neutral proteinase (CANP; calpain) activity in Schwann cells: immunofluorescence localization and compartmentation of mu- and mCANP". Journal of Neuroscience Research. 29 (3): 346–54. doi:10.1002/jnr.490290310. PMID1656060. S2CID40120102.
Ohno S, Minoshima S, Kudoh J, Fukuyama R, Shimizu Y, Ohmi-Imajoh S, Shimizu N, Suzuki K (1990). "Four genes for the calpain family locate on four distinct human chromosomes". Cytogenetics and Cell Genetics. 53 (4): 225–9. doi:10.1159/000132937. PMID2209092.
Andersson B, Wentland MA, Ricafrente JY, Liu W, Gibbs RA (April 1996). "A "double adaptor" method for improved shotgun library construction". Analytical Biochemistry. 236 (1): 107–13. doi:10.1006/abio.1996.0138. PMID8619474.