ANGPTL3
Encyclopedia
Angiopoietin-like 3, also known as ANGPTL3, is a protein
which in humans is encoded by the ANGPTL3 gene
.
-like family of secreted factors. It is predominantly expressed in the liver, and has the characteristic structure of angiopoietins, consisting of a signal peptide
, N-terminal coiled-coil domain and the C-terminal fibrinogen
(FBN)-like domain. The FBN-like domain in angiopoietin-like 3 protein was shown to bind alpha-5/beta-3 integrins
, and this binding induced endothelial cell adhesion
and migration
. This protein may also play a role in the regulation of angiogenesis
.
Angptl3 also acts as dual inhibitor of LPL and EL, and increases plasma triglyceride and HDL cholesterol in rodents. ANGPTL3 inhibit endothelial lipase to catalyze HDL-phospholipid and increase HDL-PL levels. Circulating PL-riched HDL particles have high cholesterol efflux abilities. In human, ANGPTL3 is a determinant factor of HDL level and positively correlates with plasma HDL cholesterol.
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
which in humans is encoded by the ANGPTL3 gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
.
Function
The protein encoded by this gene is a member of the angiopoietinAngiopoietin
The angiopoietins are protein growth factors that promote angiogenesis, the formation of blood vessels from pre-existing blood vessels. There are now four identified angiopoietins:...
-like family of secreted factors. It is predominantly expressed in the liver, and has the characteristic structure of angiopoietins, consisting of a signal peptide
Signal peptide
A signal peptide is a short peptide chain that directs the transport of a protein.Signal peptides may also be called targeting signals, signal sequences, transit peptides, or localization signals....
, N-terminal coiled-coil domain and the C-terminal fibrinogen
Fibrinogen
Fibrinogen is a soluble plasma glycoprotein, synthesised by the liver, that is converted by thrombin into fibrin during blood coagulation. This is achieved through processes in the coagulation cascade that activate the zymogen prothrombin to the serine protease thrombin, which is responsible for...
(FBN)-like domain. The FBN-like domain in angiopoietin-like 3 protein was shown to bind alpha-5/beta-3 integrins
Alpha-v beta-3
αVβ3 is a type of integrin that is a receptor for vitronectin. It consists of two components, integrin alpha V and integrin beta 3 , and is expressed by platelets. Furthermore it is a receptor for phagocytosis on macrophages or dendritic cells....
, and this binding induced endothelial cell adhesion
Cell adhesion
Cellular adhesion is the binding of a cell to a surface, extracellular matrix or another cell using cell adhesion molecules such as selectins, integrins, and cadherins. Correct cellular adhesion is essential in maintaining multicellular structure...
and migration
Cell migration
Cell migration is a central process in the development and maintenance of multicellular organisms. Tissue formation during embryonic development, wound healing and immune responses all require the orchestrated movement of cells in particular directions to specific locations...
. This protein may also play a role in the regulation of angiogenesis
Angiogenesis
Angiogenesis is the physiological process involving the growth of new blood vessels from pre-existing vessels. Though there has been some debate over terminology, vasculogenesis is the term used for spontaneous blood-vessel formation, and intussusception is the term for the formation of new blood...
.
Angptl3 also acts as dual inhibitor of LPL and EL, and increases plasma triglyceride and HDL cholesterol in rodents. ANGPTL3 inhibit endothelial lipase to catalyze HDL-phospholipid and increase HDL-PL levels. Circulating PL-riched HDL particles have high cholesterol efflux abilities. In human, ANGPTL3 is a determinant factor of HDL level and positively correlates with plasma HDL cholesterol.