Molecular cloning, sequence analysis and expression distribution of an aminopeptidase in Aplysia california.
We are investigating the role of membrane-bound peptidases in the inactivation of neuropeptides in Aplysia californica. Recently, we reported the biochemical characterization of a membrane-bound neuropeptide-degrading enzyme which has enzymatic characteristics similar to those of the mammalian aminopeptidase N (Bawab W, Querido E, Crine P, DesGroseillers L. Identification and characterization of aminopeptidases from Aplysia californica, Biochem J 1992;286:967-975). We now report the cloning and sequencing of a cDNA encoding an aminopeptidase enzyme (apAP) and the localization of the apAP transcript in Aplysia. The apAP cDNA encodes a putative protein of 1007 amino acids, which shows around 34% sequence identity to mammalian aminopeptidases A and N sequences. The deduced amino acid sequence suggests that apAP is a type II membrane-bound protein, with a long extracellular domain in which the consensus sequence of zinc-binding metallopeptidases (His-Glu-Xxx-Xxx-His) is found. RT-PCR and Northern blot experiments showed that the apAP gene is expressed as a single 6.8-kb transcript in the central nervous system, gill, heart, kidney and ovotestis.
Wickham
L
L
Département de Biochimie, Faculté de Médecine, Université de Montréal, Québec, Canada.
Zappulla
J P
JP
DesGroseillers
L
L
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000626:Aminopeptidases / Q000235:genetics* / Q000378:metabolism*; D000818:Animals; D001048:Aplysia / Q000201:enzymology* / Q000235:genetics*; D001483:Base Sequence; D015139:Blotting, Southern; D003001:Cloning, Molecular; D015971:Gene Expression Regulation, Enzymologic; D008969:Molecular Sequence Data; D009479:Neuropeptides / Q000378:metabolism; D017421:Sequence Analysis; D017386:Sequence Homology, Amino Acid; D014158:Transcription, Genetic
D009479:Neuropeptides; D000626:Aminopeptidases