Syncytin

Syncytin is a protein that is encoded by the genes ERVW-1 and ERVFRD-1 in humans. These genes are part of the endogenous retrovirus family, which are remnants of ancient viral infections that have been incorporated into the human genome. Syncytin plays a crucial role in the formation of the placenta during pregnancy, specifically in the process of cell fusion that forms the syncytiotrophoblast, a layer of the placenta that facilitates nutrient and gas exchange between the mother and fetus.

Function

Syncytin proteins are essential for the formation of the syncytiotrophoblast, a multinucleated cell layer that forms the outermost layer of the placenta. The syncytiotrophoblast is responsible for the exchange of nutrients, gases, and waste products between the mother and the fetus. Syncytin proteins facilitate the fusion of cytotrophoblast cells to form the syncytiotrophoblast.

Structure

Syncytin proteins are glycoproteins that are embedded in the cell membrane. They have a characteristic structure that includes a signal peptide, a fusion peptide, and a transmembrane domain. The fusion peptide is responsible for the fusion of cytotrophoblast cells, while the transmembrane domain anchors the protein in the cell membrane.

Clinical significance

Alterations in the expression or function of syncytin proteins can lead to placental abnormalities and pregnancy complications, such as preeclampsia and intrauterine growth restriction. In addition, some studies have suggested that syncytin proteins may be involved in the pathogenesis of certain neurological disorders, such as multiple sclerosis, due to their ability to mediate cell fusion and inflammation.

File:Syncytin.jpg

Syncytin proteins mediate the fusion of cytotrophoblast cells to form the syncytiotrophoblast.

See also

• Endogenous retrovirus
• Placenta
• Cell fusion
• Pregnancy