Calpain | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
![]() Crystal structure of the peptidase core of Calpain II. | |||||||||||
Identifiers | |||||||||||
Symbol | Calpain | ||||||||||
Pfam | PF00648 | ||||||||||
Pfam clan | CL0125 | ||||||||||
InterPro | IPR001300 | ||||||||||
SMART | CysPc | ||||||||||
PROSITE | PDOC50203 | ||||||||||
MEROPS | C2 | ||||||||||
SCOP2 | 1mdw / SCOPe / SUPFAM | ||||||||||
|
calpain-1 | |||||||||
---|---|---|---|---|---|---|---|---|---|
Identifiers | |||||||||
EC no. | 3.4.22.52 | ||||||||
CAS no. | 689772-75-6 | ||||||||
Databases | |||||||||
IntEnz | IntEnz view | ||||||||
BRENDA | BRENDA entry | ||||||||
ExPASy | NiceZyme view | ||||||||
KEGG | KEGG entry | ||||||||
MetaCyc | metabolic pathway | ||||||||
PRIAM | profile | ||||||||
PDB structures | RCSB PDB PDBe PDBsum | ||||||||
|
calpain-2 | |||||||||
---|---|---|---|---|---|---|---|---|---|
Identifiers | |||||||||
EC no. | 3.4.22.53 | ||||||||
CAS no. | 702693-80-9 | ||||||||
Databases | |||||||||
IntEnz | IntEnz view | ||||||||
BRENDA | BRENDA entry | ||||||||
ExPASy | NiceZyme view | ||||||||
KEGG | KEGG entry | ||||||||
MetaCyc | metabolic pathway | ||||||||
PRIAM | profile | ||||||||
PDB structures | RCSB PDB PDBe PDBsum | ||||||||
|
A calpain (/ˈkælpeɪn/;[1] EC 3.4.22.52, EC 3.4.22.53) is a protein belonging to the family of calcium-dependent, non-lysosomal cysteine proteases (proteolytic enzymes) expressed ubiquitously in mammals and many other organisms. Calpains constitute the C2 family of protease clan CA in the MEROPS database. The calpain proteolytic system includes the calpain proteases, the small regulatory subunit CAPNS1, also known as CAPN4, and the endogenous calpain-specific inhibitor, calpastatin.