Calpain 1 Mouse Monoclonal Antibody [2A1]

Function

Calpain 1 (large subunit), also designated µ-calpain, is an intracellular calcium-dependent protease that cleaves cyto-skeletal and submembranous proteins. Calpains are nonlysosomal, calcium-activated intracellular cysteine proteases. Calpains mediate specific Ca2+-dependent processes including cell fusion, mitosis and meiosis. Calpains are heterodimers of a small regulatory subunit and one of three large catalytic subunits, designated Calpain 1 (large subunit), Calpain 2 and Calpain p94. Calpastatin regulates Calpain by inhibiting both the proteolytic activity of Calpain and its binding to membranes. Calpastatin exists in two types, tissue type and erythrocyte type, resulting from both alternative splicing and proteolytic processing. Calpain-1 co-localizes with human leukocyte antigen-DR (HLA-DR) on activated microglia in the aging brain. Calpain influences the process of spermatogenesis and the events preceding fertilization, such as the acrosome reaction.

Background References

1. Liu X et al. Mitochondrial calpain-1 activates NLRP3 inflammasome by cleaving ATP5A1 and inducing mitochondrial ROS in CVB3-induced myocarditis. Basic Res Cardiol. 2022 Aug

2. Wei S et al. Calpain-1 Up-Regulation Promotes Bleomycin-Induced Pulmonary Fibrosis by Activating Ferroptosis. Am J Pathol. 2024 Dec

Sequence Similarity

Belongs to the peptidase C2 family.

Tissue Specificity

Ubiquitous.

Post-translational Modification

Undergoes calcium-induced successive autoproteolytic cleavages that generate a membrane-bound 78 kDa active form and an intracellular 75 kDa active form. Calpastatin reduces with high efficiency the transition from 78 kDa to 75 kDa calpain forms.

Subcellular Location

Plasma membrane.

UNIPROT

SwissProt: P07384 Human

SwissProt: P97571 Rat

Synonyms