Sequence analysis of the Acetylcholinesterase 1 translated from messenger Ribonucleic Acid of the nervous system of crayfish ( Cherax quadricarinatus Martens , 1868)

摘要

Crayfish are the animal models used as biomarkers of exposure to pesticides. Some compounds such as organophosphates work by blocking Acetylcholinesterase (AChE), an enzyme that hydrolyzes the neurotransmitter acetylcholine on cholinergic synapses. In inse cts recurrent exposure to pesticides produces resistance, and the molecular analysis has identified mutations as the cause of this resistance. Till date, there are a few sequences reported for crustaceans. Even more, there are no reports of sequences in an y species of crayfish that allow make comparative studies. In this study, we obtained the specific sequence of messenger Ribonucleic acid (mRNA) for the AChE1 protein from the crayfish, Cherax quadricarinatus . The mRNA was isolated from abdominal nerve cor d of C. quadricarinatus . Degenerate oligonucleotides were used and the 1242 nucleotides sequence was directly obtained from PCR products. We have deposited this sequence with the accession number [GenBank KT007499]. Analysis of the 414 amino acid residues of the putative AChE protein showed a high homology to the Esterase - lipase super family. We identified 60% to 64% similarity of AChE1 in insects and crustaceans with well - conserved AChE1 main domains. We concluded that the partial sequence analysis to this putative mRNA and the comparative studies with other species clearly shows that the sequence corresponds to the translated product Acetylcholinesterase - 1.