Human Apolipoprotein A-IV

Abstract

Human apolipoprotein A-IV is a member of a family of proteins involved in lipoprotein metabolism. It differs from the other apolipoproteins by physical and chemical properties which allow it to exist in a lipoprotein-free form in plasma. ApoA-IV is synthesised primarily in the intestine and in the liver, and its production is regulated during development. Its expression is also modulated by different effectors such as nutrients and hormones. Its physiological role remains poorly understood. Aside from its implication in reverse cholesterol transport, it could also have a function in the absorption and export of triglycerides; however the relation between these roles remains to be established. Insights into the molecular biology of the apoA-IV gene, which arises from an ancestor gene common to the soluble apolipoprotein genes, will help to clarify the physiological role of this protein