Page last updated: 2024-10-24
calpain complex
Definition
Target type: cellularcomponent
A calcium-dependent protease complex that processes its substrate by limited proteolysis rather than degrading it. In some cases limited proteolysis is required for the activation of its substrate. [GOC:bhm, PMID:10639123]
The calpain complex is a multi-protein complex involved in calcium-dependent proteolysis. The core of the complex consists of two subunits: calpain 1 (CAPN1) and calpain 2 (CAPN2). These are cysteine proteases with a catalytic domain that is responsible for cleaving peptide bonds. While the catalytic domain is similar between calpain 1 and calpain 2, they have distinct regulatory domains and are activated by different calcium concentrations. Calpain 1 is activated by low concentrations of calcium, while calpain 2 requires higher concentrations. These different activation thresholds suggest that calpain 1 and 2 may have distinct cellular functions. The complex is further regulated by a variety of other proteins, including calpastatin, which is an endogenous inhibitor of calpain activity, and proteins involved in calcium signaling and trafficking. Calpain complexes are found in the cytoplasm, but they can also be associated with the plasma membrane, the cytoskeleton, and other cellular structures. This localization allows them to regulate a wide range of cellular processes, including cell signaling, cytoskeletal remodeling, cell migration, and apoptosis.'
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Proteins (3)
| Protein | Definition | Taxonomy |
|---|---|---|
| Calpain-2 catalytic subunit | A calpain-2 catalytic subunit that is encoded in the genome of human. [PRO:DNx, UniProtKB:P17655] | Homo sapiens (human) |
| Calpain-1 catalytic subunit | A calpain-1 catalytic subunit that is encoded in the genome of human. [PRO:DNx, UniProtKB:P07384] | Homo sapiens (human) |
| Calpain small subunit 1 | A calpain small subunit 1 that is encoded in the genome of human. [PRO:DNx, UniProtKB:P04632] | Homo sapiens (human) |
Compounds (22)
| Compound | Definition | Classes | Roles |
|---|---|---|---|
| celecoxib | organofluorine compound; pyrazoles; sulfonamide; toluenes | cyclooxygenase 2 inhibitor; geroprotector; non-narcotic analgesic; non-steroidal anti-inflammatory drug | |
| rofecoxib | butenolide; sulfone | analgesic; cyclooxygenase 2 inhibitor; non-steroidal anti-inflammatory drug | |
| isoquinoline-1,3,4-trione | isoquinoline-1,3,4-trione: structure in first source | ||
| aloxistatin | aloxistatin : An L-leucine derivative that is the amide obtained by formal condensation of the carboxy group of (2S,3S)-3-(ethoxycarbonyl)oxirane-2-carboxylic acid with the amino group of N-(3-methylbutyl)-L-leucinamide. aloxistatin: a membrane-permeable cysteine protease inhibitor | epoxide; ethyl ester; L-leucine derivative; monocarboxylic acid amide | anticoronaviral agent; cathepsin B inhibitor |
| carbobenzoxyvalylphenylalanine aldehyde | Z-Val-Phe-H : A dipeptide resulting from the formal condensation of the carboxy group of N-benzyloxycarbonyl-L-valine with the amino group of L-phenylalanine aldehyde. It is a potent cell-permeable inhibitor of calpain I and II, and is also a gamma-secretase inhibitor. | aldehyde; carbamate ester; dipeptide | antileishmanial agent; apoptosis inhibitor; EC 3.4.22.52 (calpain-1) inhibitor; EC 3.4.22.53 (calpain-2) inhibitor; EC 3.4.23.46 (memapsin 2) inhibitor |
| calpeptin | amino acid amide | ||
| n-(n-(3-carboxyoxirane-2-carbonyl)leucyl)isoamylamine | N-(N-(3-carboxyoxirane-2-carbonyl)leucyl)isoamylamine: inhibits calcium-activated neutral protease; see also record for E-64; RN given refers to (2-S-(2alpha,3beta)(R*)-isomer) | leucine derivative | |
| e 64 | E 64: cysteine protease inhibitor of microbial origin, which inhibits cathepsin B (EC 3.4.22.1) and cathepsin L (EC 3.4.22.-) | dicarboxylic acid monoamide; epoxy monocarboxylic acid; guanidines; L-leucine derivative; zwitterion | antimalarial; antiparasitic agent; protease inhibitor |
| acetylleucyl-leucyl-norleucinal | acetylleucyl-leucyl-norleucinal : A tripeptide composed of N-acetylleucyl, leucyl and norleucinal residues joined in sequence. acetylleucyl-leucyl-norleucinal: a proteasome inhibitor | aldehyde; tripeptide | cysteine protease inhibitor |
| benzyloxycarbonylleucyl-leucyl-leucine aldehyde | benzyloxycarbonylleucyl-leucyl-leucine aldehyde: proteasome inhibitor N-benzyloxycarbonyl-L-leucyl-L-leucyl-L-leucinal : A tripeptide that is L-leucyl-L-leucyl-L-leucine in which the C-terminal carboxy group has been reduced to the corresponding aldehyde and the N-terminal amino group is protected as its benzyloxycarbonyl derivative. | amino aldehyde; carbamate ester; tripeptide | proteasome inhibitor |
| benzyloxycarbonyl-phe-ala-fluormethylketone | cathepsin B inhibitor : A cysteine protease inhibitor which inhibits cathepsin B (EC 3.4.22.1). | ||
| 3-deoxysappanchalcone | 2'-O-methylisoliquiritigenin : A member of the class of chalcones that is isoliquiritigenin in which one of the hydroxy groups at position 2' is replaced by a methoxy group. 3-deoxysappanchalcone: Anti-allergic from the roots and heartwood of Caesalpinia sappan; structure in first source | chalcones; monomethoxybenzene; phenols | metabolite |
| snj-1945 | ((1S)-1-((((1S)-1-benzyl-3-cyclopropylamino-2,3-di-oxopropyl)amino)carbonyl)-3-methylbutyl)carbamic acid 5-methoxy-3-oxapentyl ester: calpain inhibitor | ||
| phenylalanyl-valine | Val-Phe : A dipeptide formed from L-valine and L-phenylalanine residues. | dipeptide | metabolite |
| ca 074 | |||
| a-705253 | A-705253: structure in first source | ||
| sja 6017 | N-(4-fluorophenylsulfonyl)-L-valyl-L-leucinal: structure in first source | ||
| phevalin | phevalin : A member of the class of pyrazinones that is pyrazin-2(1H)-one substituted by an isopropyl and benzyl groups at position 3 and 6, respectively. It is a natural product found in Staphylococcus aureus that inhibits calpain in a casein hydrolysis assay (IC50 = 1.3 muM), contributes to S. aureus infection in mice, and alters human keratinocyte gene expression. phevalin: isolated from a Streptomyces sp.; structure given in first source | benzenes; pyrazinone | bacterial metabolite; calpain inhibitor |
| calpain inhibitor iii | calpain inhibitor III: potential anticataract drug | ||
| PF-00835231 | PF-00835231 : A primary alcohol resulting from the cleavage of the phosphate group of the prodrug PF-07304814. It is an inhibitor of SARS-CoV-1 and -2 main protease (3CLpro) and exhibits potent in vitro antiviral activity. | aromatic ether; indolecarboxamide; L-leucine derivative; primary alcohol; pyrrolidin-2-ones; secondary carboxamide | anticoronaviral agent; drug metabolite; EC 3.4.22.69 (SARS coronavirus main proteinase) inhibitor |
| grassystatin a | grassystatin A: isolated from a cyanobacterium, identified as Lyngbya cf.; structure in first source | ||
| N-[(2S)-3-cyclohexyl-1-oxo-1-({(2S)-1-oxo-3-[(3S)-2-oxopyrrolidin-3-yl]propan-2-yl}amino)propan-2-yl]-1H-indole-2-carboxamide | N-[(2S)-3-cyclohexyl-1-oxo-1-({(2S)-1-oxo-3-[(3S)-2-oxopyrrolidin-3-yl]propan-2-yl}amino)propan-2-yl]-1H-indole-2-carboxamide : A secondary carboxamide resulting from the formal condensation of the carboxy group of 1H-indole-2-carboxylic acid with the primary amino group of 3-cyclohexyl-N-{(2S)-1-oxo-3-[(3S)-2-oxopyrrolidin-3-yl]propan-2-yl}-L-alaninamide. It is an inhibitor of SARS coronavirus main proteinase and inhibits SARS-CoV-2 replication in cell culture (EC50 = 0.53 muM). | aldehyde; indolecarboxamide; oligopeptide; pyrrolidin-2-ones; secondary carboxamide | anticoronaviral agent; EC 3.4.22.69 (SARS coronavirus main proteinase) inhibitor |