Sialic acid-binding immunoglobulin-like lectins (Siglecs) are cell surface receptors of the I-type lectin family that are expressed on innate immune cells and bind to sialylated and non-sialylated ligands. Myelin-Associated Glycoprotein (MAG), also known as Siglec-4a, is a type I transmembrane glycoprotein belonging to the Siglec family, a subgroup of the Ig superfamily. It is selectively expressed by myelinating cells including Schwann cells in the peripheral nervous system (PNS) and oligodendrocytes in the central nervous system (CNS). It is encoded by a single gene that is conserved among vertebrates. It is composed of an extracellular segment containing five Ig-like domains, a single transmembrane segment, and a cytoplasmic domain. Mature MAG exists as two isoforms, termed S-MAG (short) and L-MAG (long), due to alternative splicing of the cytoplasmic domain.
中文
