ATG4A Human Recombinant Protein

Autophagy is the process by which endogenous proteins and damaged organelles are destroyed intracellularly. Autophagy is postulated to be essential for cell homeostasis and cell remodeling during differentiation, metamorphosis, non-apoptotic cell death, and aging. Reduced levels of autophagy have been described in some malignant tumors, and a role for autophagy in controlling the unregulated cell growth linked to cancer has been proposed. This gene encodes a member of the autophagin protein family. The encoded protein is also designated as a member of the C-54 family of cysteine proteases. Transcript variants that encode distinct isoforms have been identified. [provided by RefSeq, Jul 2008]

ATG4A: Cysteine protease required for autophagy, which cleaves the C-terminal part of either MAP1LC3, GABARAPL2 or GABARAP, allowing the liberation of form I. A subpopulation of form I is subsequently converted to a smaller form (form II). Form II, with a revealed C-terminal glycine, is considered to be the phosphatidylethanolamine (PE)-conjugated form, and has the capacity for the binding to autophagosomes. Preferred substrate is GABARAPL2 followed by MAP1LC3A and GABARAP. Widely expressed, at a low level, and the highest expression is observed in skeletal muscle and brain. Also detected in fetal liver. Inhibited by N-ethylmaleimide. Belongs to the peptidase C54 family. 4 isoforms of the human protein are produced by alternative splicing.

Protein type: EC 3.4.22.-; Microtubule-binding; Autophagy; Protease

Chromosomal Location of Human Ortholog: Xq22.3

Cellular Component: cytoplasm; cytosol

Molecular Function: cysteine-type endopeptidase activity; cysteine-type peptidase activity

Biological Process: protein delipidation; mitochondrion degradation; C-terminal protein lipidation; protein processing; protein targeting to membrane; proteolysis; autophagic vacuole formation; cellular response to nitrogen starvation