Angiopoietin-like protein 3 (Angptl3) functions as a potent lipoprotein lipase inhibitor and is an important component of plasma triglyceride homeostasis. Angptl3 also plays a role in adipose formation and angiogenesis through its interaction with integrin ?v)beta(3). It is secreted by the liver and is functionally defined by the C-terminal fibrinogen (FBN)-like domain and an N-terminal coiled-coil domain. Angptl3 regulates circulating triglyceride levels during different nutritional states thereby mediating the feeding/fasting cycle. A deficiency of Angptl3 results in abnormally low lipid levels, and a repression of the protein may be protective against atherosclerosis. Angptl3 may also play an important role in hyperlipidemia in diabetes.