GSTA4

Glutathione S-transferase A4, also known as GSTA4, is an is_associated_with::enzyme which in humans is encoded by the GSTA4 is_associated_with::gene.

Function
Cytosolic and membrane-bound forms of is_associated_with::glutathione S-transferase are encoded by two distinct supergene families. These enzymes are involved in cellular defense against toxic, carcinogenic, and pharmacologically active is_associated_with::electrophilic compounds. At present, eight distinct classes of the soluble cytoplasmic mammalian glutathione S-transferases have been identified: alpha, kappa, mu, omega, pi, sigma, theta and zeta. This gene encodes a glutathione S-tranferase belonging to the alpha class. The alpha class genes, which are located in a cluster on chromosome 6, are highly related and encode enzymes with is_associated_with::glutathione peroxidase activity that function in the detoxification of lipid peroxidation products.

GSTA4 shows very high activity with reactive carbonyl compounds such as alk-2-enals. GSTA4 is highly effective in catalyzing the conjugate addition of reduced is_associated_with::glutathione to 4-hydroxynonenal, an important product of peroxidative degradation of is_associated_with::arachidonic acid and a commonly used is_associated_with::biomarker for oxidative damage in tissue.

Clinical significance
Reactive electrophiles produced by oxidative metabolism have been linked to a number of degenerative diseases including is_associated_with::Parkinson's disease, is_associated_with::Alzheimer's disease, is_associated_with::cataract formation, and is_associated_with::atherosclerosis hence reduced expression of the GSTA4 enzyme may have pathophysiological consequences. The expression of this gene is decreased drastically among burn and trauma victims.