title: Myelin and lymphocyte protein (MAL/MVP17/VIP17) and plasmolipin are members of an extended gene family.
abstract: An increasing number of four-transmembrane proteins has been found to be associated with CNS and PNS myelin. Some of these proteins play crucial roles in the development and maintenance of the nervous system. In the CNS, proteolipid protein (PLP) is mutated in the myelin disorder Pelizaeus-Merzbacher disease and in spastic paraplegia, while in the PNS, peripheral myelin protein 22 (PMP22) and connexin32 (C x 32) are culprit genes in the most frequent forms of hereditary peripheral neuropathies. Myelin and lymphocyte protein (MAL; also called MVP17 or VIP17) and plasmolipin are additional tetraspan proteins that are highly expressed by myelinating glial cells. However, little is known about the role of these proteins in the nervous system. As a prerequisite for functional genetic approaches in the mouse, we have isolated and characterized a mouse MAL cDNA and the corresponding structural MAL gene. Computer-aided analysis and database searches revealed that MAL belongs to a larger gene family which also includes plasmolipin, BENE and the expressed sequence tag (EST) H09290. While the overall amino acid sequence identities between mouse MAL and the related proteins are relatively low (29-37%), the conserved motif -[Q/Y-G-W-V-M-F/Y-V]- which is found at the junction of the first extracellular loop and the second membrane-associated domain serves as a fingerprint for the MAL protein family. Expression analysis of the members of the MAL gene family indicates widespread expression in various tissues, suggesting a common role of these proteins in cell biology.
authors.affiliation: Department of Biology, Institute of Cell Biology, Swiss Federal Institute of Technology, Zurich.
authors.forename: J P
authors.initials: JP
authors.lastname: Magyar
authors.forename: C
authors.initials: C
authors.lastname: Ebensperger
authors.forename: N
authors.initials: N
authors.lastname: Schaeren-Wiemers
authors.forename: U
authors.initials: U
authors.lastname: Suter
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000032:analysis; D005796:Genes; D006801:Humans; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D051379:Mice; D008969:Molecular Sequence Data; D005810:Multigene Family; D009185:Myelin Proteins / Q000235:genetics*; D062806:Myelin and Lymphocyte-Associated Proteolipid Proteins; D009419:Nerve Tissue Proteins; D009928:Organ Specificity / Q000235:genetics; D011510:Proteolipids / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D013601:T-Lymphocytes / Q000737:chemistry
chemical_list: D018076:DNA, Complementary; C569026:MAL protein, human; C569027:Mal protein, mouse; C569028:Mal protein, rat; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D009185:Myelin Proteins; D062806:Myelin and Lymphocyte-Associated Proteolipid Proteins; D009419:Nerve Tissue Proteins; C048897:PLLP protein, human; C489075:Pllp protein, mouse; C489076:Pllp protein, rat; D011510:Proteolipids; D012333:RNA, Messenger