title: The highly conserved synapse protein SNAP-25 displays sequence variability in the cockroach Leucophaea maderae.
abstract: SNAP-25 (synaptosome-associated protein of 25 kD) is attached to the intracellular side of presynaptic membranes where it serves as a target receptor for the vesicle docking machinery prior to release of neurotransmitter. SNAP-25 displays a high degree of sequence conservation between vertebrates and Drosophila melanogaster. To obtain more information about conserved regions of SNAP-25, we have isolated cDNA clones from the cockroach Leucophaea maderae. One clone (Lm1) encoded a full-length SNAP-25 protein and its deduced amino acid sequence is 77% identical to Drosophila SNAP-25. Surprisingly, the cockroach protein is 17 amino acids shorter than Drosophila SNAP-25 at the carboxy terminus. Four other cDNA clones encode parts of SNAP-25 and each clone has distinct characteristics, including amino acid replacements and unique carboxy termini. Thus, the highly conserved protein SNAP-25 displays unexpected sequence variability in the cockroach that may indicate specialized SNAP-25 isoforms.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003058:Cockroaches / Q000737:chemistry*; D017124:Conserved Sequence; D029721:Drosophila Proteins; D015723:Gene Library; D008565:Membrane Proteins; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000737:chemistry*; D011110:Polymorphism, Genetic; D017386:Sequence Homology, Amino Acid; D050825:Synaptosomal-Associated Protein 25