VAP proteins are conserved integral membrane proteins of the endoplasmic reticulum found in all eukaryotic cells .[ 1] VAP stands for V AMP-a ssociated p rotein,[ 2] where VAMP stands for vesicle-associated membrane protein . Humans have two VAPs that consist of the essential Major Sperm Protein domain and linker plus transmembrane helix to attach to the ER: VAPA and VAPB .[ 3] A third VAP-like protein is Motile sperm domain containing 2 (MOSPD2) , which has all the elements of VAP, and like them binds FFAT motifs , but has at its N-terminus a CRAL-TRIO domain that can bind and transfer lipids.[ 4]
VAP includes the whole family of protein homologues in all species. For example, baker's yeast expresses two VAPs: Scs2 and Scs22 .[ 5] [ 6]
^ Weir ML, Klip A, Trimble WS (July 1998). "Identification of a human homologue of the vesicle-associated membrane protein (VAMP)-associated protein of 33 kDa (VAP-33): a broadly expressed protein that binds to VAMP" . The Biochemical Journal . 333 (2): 247–51. doi :10.1042/bj3330247 . PMC 1219579 . PMID 9657962 .
^ Skehel PA, Martin KC, Kandel ER, Bartsch D (September 1995). "A VAMP-binding protein from Aplysia required for neurotransmitter release". Science . 269 (5230): 1580–3. Bibcode :1995Sci...269.1580S . doi :10.1126/science.7667638 . PMID 7667638 .
^ Nishimura Y, Hayashi M, Inada H, Tanaka T (January 1999). "Molecular cloning and characterization of mammalian homologues of vesicle-associated membrane protein-associated (VAMP-associated) proteins". Biochemical and Biophysical Research Communications . 254 (1): 21–6. doi :10.1006/bbrc.1998.9876 . PMID 9920726 .
^ Di Mattia, Thomas; Wilhelm, Léa P.; Ikhlef, Souade; Wendling, Corinne; Spehner, Danièle; Nominé, Yves; Giordano, Francesca; Mathelin, Carole; Drin, Guillaume; Tomasetto, Catherine; Alpy, Fabien (July 2018). "Identification of MOSPD2, a novel scaffold for endoplasmic reticulum membrane contact sites" . EMBO Reports . 19 (7). doi :10.15252/embr.201745453 . ISSN 1469-3178 . PMC 6030701 . PMID 29858488 .
^ Nikawa J, Murakami A, Esumi E, Hosaka K (July 1995). "Cloning and sequence of the SCS2 gene, which can suppress the defect of INO1 expression in an inositol auxotrophic mutant of Saccharomyces cerevisiae". Journal of Biochemistry . 118 (1): 39–45. doi :10.1093/oxfordjournals.jbchem.a124889 . PMID 8537323 .
^ Loewen CJ, Levine TP (April 2005). "A highly conserved binding site in vesicle-associated membrane protein-associated protein (VAP) for the FFAT motif of lipid-binding proteins" . The Journal of Biological Chemistry . 280 (14): 14097–104. doi :10.1074/jbc.M500147200 . PMID 15668246 .