Homodimer. Isoform 3 exists as a homodimer.

Myelin membrane; Peripheral membrane protein; Cytoplasmic side. Note=Cytoplasmic side of myelin.

MBP isoforms are found in both the central and the peripheral nervous system, whereas Golli-MBP isoforms are expressed in fetal thymus, spleen and spinal cord, as well as in cell lines derived from the immune system.

Several charge isomers of MBP; C1 (the most cationic, least modified, and most abundant form), C2, C3, C4, C5, C6, C7, C8-A and C8-B (the least cationic form); are produced as a result of optional PTM, such as phosphorylation, deamidation of glutamine or asparagine, arginine citrullination and methylation. C8-A and C8-B contain each two mass isoforms termed C8-A(H), C8-A(L), C8-B(H) and C8-B(L), (H) standing for higher and (L) for lower molecular weight. C3, C4 and C5 are phosphorylated. The ratio of methylated arginine residues decreases during aging, making the protein more cationic.
The N-terminal alanine is acetylated (isoform 3, isoform 4, isoform 5 and isoform 6).
Arg-241 was found to be 6% monomethylated and 60% symmetrically dimethylated.
Phosphorylated by TAOK2, VRK2, MAPK11, MAPK12, MAPK14 and MINK1.

Belongs to the myelin basic protein family.

Entrez Gene: 4155 Human

Entrez Gene: 17196 Mouse

Entrez Gene: 414286 Pig

Entrez Gene: 24547 Rat

Omim: 159430 Human

SwissProt: P02686 Human

SwissProt: P04370 Mouse

SwissProt: P81558 Pig

SwissProt: P25274 Rabbit

SwissProt: P02688 Rat

Unigene: 551713 Human

Unigene: 63285 Rat

Oligodendrocyte Marker
The classic group of Myelin basic protein (MBP) isoforms (isoforms 4 to 14) are with PLP the most abundant protein components of the myelin membrane in the CNS. They have a role in both its formation and stabilization. The smaller isoforms might have an important role in remyelination of denuded axons in multiple sclerosis. The non classic group of MBP isoforms (isoforms 1 to 3/Golli MBPs) may preferentially have a role in the early developing brain long before myelination, maybe as components of transcriptional complexes, and may also be involved in signaling pathways in T cells and neural cells. Differential splicing events combined to optional posttranslational modifications give a wide spectrum of isomers, each of them having maybe a specialized function.