Neuronal membrane glycoprotein M6-b (GPM6B)

Neuronal membrane glycoprotein M6-b (GPM6B) is a four-pass transmembrane protein belonging to the proteolipid protein family, encoded by the GPM6B gene on the human X chromosome[1][5][11]. GPM6B is expressed mainly in neurons, oligodendrocytes, and astrocytes within the central nervous system and is also found in osteoblasts[1][2][7][11]. It mediates cell-to-cell contact and regulates membrane growth, composition, and trafficking. Biologically, it plays roles in neural development, myelination, axonal growth, synaptic function, and the negative regulation of serotonin uptake via the serotonin transporter (SERT)[7][5][11]. Beyond neural tissue, GPM6B contributes to osteoblast differentiation, regulation of bone mineralization, actin cytoskeleton organization, and matrix vesicle release necessary for bone formation[1][10][2][5]. GPM6B has emerged as a candidate implicated in neuropsychiatric conditions (through genetic association studies and animal models affecting decision-making and impulsivity), certain leukemias (as a potential oncogene), myelin and bone disorders, and cancer progression through decreased expression in glioblastoma[2][5][7]. No specific drugs directly target GPM6B at present, but its regulatory effect on serotonin uptake makes it of interest for neuropsychiatric research and potential pharmacological modulation indirectly via the serotonin transporter[7][5].

Other names

GPM6BM6BM6bMGC17150MGC54284protolipid M6Bglycoprotein membrane 6B

Not direct pharmacological mechanisms identified; however, GPM6B downregulates serotonin uptake by internalization of the serotonin transporter, which may be indirectly relevant for psychoactive drug response or serotonergic modulation[7][5].