9.B.38 The Myelin Proteolipid Protein (MPLP) Family
The MPLP family consists mostly of animal proteins of 4 TMSs. The prototype is glycoprotein M6a, a CNS neuronal protein found in the granuole cell layer of the embryonic neural tube. It is present in synaptic vesicles and listed as a transporter (Takamori et al., 2006). The mouse protein is of 278 aas with 4 TMSs. Its first half is very similar to the 2 TMS Pelizaeus-Merzbacher disease protein of humans. A Tetrahymena homologue has 8 putative TMSs and is very distantly related to the mouse protein. This protein has a partial COG5152 domain at the C-terminus which exhibits similarity to zinc finger family members (e.g., ABF95025 of Oriza sativa) and ring finger protein 157 (e.g., CAM16808 of Mus musculus).
The PMD protein of Homo sapiens (B1B1G5)
Neuronal membrane glycoprotein M6-b (M6b) (Rhombencephalic expression protein-29 kDa) (Rhombex-29)