ATG4 Autophagy Related 4 Homolog B (ATG4B) 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. Alternate transcriptional splice variants, encoding different isoforms, have been characterized. [provided by RefSeq, Jul 2008]

ATG4B: 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. Mainly expressed in the skeletal muscle, followed by brain, heart, liver and pancreas. Inhibited by N-ethylmaleimide. Belongs to the peptidase C54 family. 5 isoforms of the human protein are produced by alternative splicing.

Protein type: Ubiquitin conjugating system; Protease; EC 3.4.22.-; Autophagy

Chromosomal Location of Human Ortholog: 2q37.3

Cellular Component: cytoplasm; cytosol

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

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