VAMP-1 has a highly variable C-terminus generated by alternative splicing.
VAMP-1 (synaptobrevin1) is one of the key proteins in the SNARE complex which is involved in regulated exocytosis. Recently, Isenmann et al. (1998, Mol. Biol. Cell 9, 1649-1660) showed the extreme C-terminal region of VAMP-1A and 1B to be involved in subcellular targeting of the isoforms. Four new splice variants (VAMP-1C to F) were identified in addition to the previously published variants VAMP-1A and VAMP-1B. Interestingly, the four new isoforms also have variable sequences only at the extreme C-terminus. This suggests that the C-terminal region has an important function for VAMP-1 and vesicle targeting. All six variants were a result of alternative splicing that linked exons 1-4 which encode the conserved region of VAMP-1 with one of the exons 5A to 5F that encodes the highly variable extreme C-terminus. Exon (5A-E) encode C-termini of two to five amino acid residues, whereas exon 5F encoded a long C-terminal amino acid extension. The splice variants were differentially expressed in human brain, kidney, and inflammatory cells.
Berglund
L
L
Protein Chemistry Laboratory, Department of Molecular and Structural Biology, University of Aarhus, Gustav Wieds Vej 10 C, Aarhus C, DK-8000, Denmark. berglund@imsb.au.dk
Hoffmann
H J
HJ
Dahl
R
R
Petersen
T E
TE
D017398:Alternative Splicing; D000595:Amino Acid Sequence; D001483:Base Sequence; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry* / Q000235:genetics*; D008969:Molecular Sequence Data; D009928:Organ Specificity; D050683:R-SNARE Proteins
D008565:Membrane Proteins; D050683:R-SNARE Proteins