PROSITE documentation PDOC00497

Myelin proteolipid protein signatures

Myelin proteolipid protein (PLP or lipophilin) [1] is the major myelin protein from the central nervous system (CNS). It probably plays an important role in the formation or maintenance of the multilamellar structure of myelin. In man point mutations in PLP are the cause of Pelizaeus-Merzbacher disease (PMD), a neurologic disorder of myelin metabolism. In animals dismyelinating diseases such as mouse 'jimpy' (jp), rat md, or dog 'shaking pup' are also caused by mutations in PLP.

PLP is a highly conserved [2] hydrophobic protein of 276 to 280 amino acids which seems to contain four transmembrane segments, two disulfide bonds and which covalently binds lipids (at least six palmitate groups in mammals) [3].

PLP is highly related to M6, a neuronal membrane glycoprotein [4].

As signature patterns for these proteins, we selected two conserved regions. The first pattern is located in the N-terminal region; at the extremity of the first transmembrane region. The second pattern is located in the extracellular loop between the last two transmembrane regions and contains a cysteine involved in a disulfide bond.