MAG
MAG (myelin-associated glycoprotein, also known as SIGLEC4A, S-MAG, SIGLEC4 and GMA) is a type I membrane adhesion molecule of the immunoglobulin superfamily. It mediates interactions between myelinating cells and neurons by binding sialylated glycoconjugates. Browse Assay Genie's current range of MAG research reagents below, or read on for the biology behind the target.
MAG is an adhesion molecule that mediates interactions between myelinating cells and neurons. It binds neuronal sialic acid-containing gangliosides, including ganglioside GT1b, and the glycoproteins RTN4R and RTN4RL2, and it preferentially binds alpha-2,3-linked sialic acid. It is not required for initial myelination, but it appears to play a role in maintaining normal axon myelination and is required to prevent degeneration of myelinated axons in adults. This probably depends on binding to gangliosides on the axon cell membrane.
MAG also acts on neurons directly. It protects motoneurons against apoptosis, including after injury, probably through interaction with neuronal RTN4R and RTN4RL2. It is a negative regulator of neurite outgrowth and inhibits axon longitudinal growth. In dorsal root ganglion neurons the inhibition is mediated mainly by RTN4R or RTN4RL2 and to a lesser degree by gangliosides. In cerebellar granule cells it is mediated mainly by gangliosides. In sensory neurons, inhibition of neurite extension depends only partly on RTN4R, RTN4RL2 and gangliosides.
The MAG gene encodes a type I membrane protein that localises to the cell membrane and membrane rafts. It belongs to the immunoglobulin superfamily and the SIGLEC (sialic acid binding Ig-like lectin) family, which is why it is also named SIGLEC4A. HGNC places it in the C2-set and I-set domain containing groups and the sialic acid binding Ig like lectins group. Three alternatively spliced transcripts encoding different isoforms have been described. Mouse and rat both carry a Mag ortholog.
MAG is thought to be involved in myelination and helps maintain normal axon myelination through myelin-neuron cell-cell interactions.
MAG negatively regulates neurite outgrowth and inhibits axon outgrowth by binding RTN4R, making it relevant to studies of axon growth inhibition.
MAG is required to prevent degeneration of myelinated axons in adults, probably through binding to gangliosides on the axon membrane.
As a SIGLEC lectin that preferentially binds alpha-2,3-linked sialic acid and ganglioside GT1b, MAG is a model for sialic acid recognition.
MAG is an adhesion molecule that mediates interactions between myelinating cells and neurons. It binds gangliosides, RTN4R and RTN4RL2, helps maintain axon myelination, protects motoneurons against apoptosis and inhibits neurite outgrowth. It is not required for initial myelination.
MAG is also known as SIGLEC4A, SIGLEC-4A, S-MAG, SIGLEC4 and GMA. The SIGLEC names reflect its membership of the sialic acid binding Ig-like lectin family. Three alternatively spliced transcripts encoding different isoforms have been described for the gene.
Yes. Both mouse and rat have a Mag ortholog of the human MAG gene. For work in a particular species, check the datasheet of any product for its validated reactivity.
Targets with similar gene symbols, listed for navigation; they are distinct from MAG in function and family.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P20916; product specifications from Assay Genie datasheets.