Molecular cloning of an acetylcholinesterase gene from the plant parasitic nematodes, Meloidogyne incognita and Meloidogyne javanica.

A gene encoding a protein with strong homology with Caenorhabditis elegans and C. briggsae acetylcholinesterase ACE-1 was cloned from Meloidogyne incognita and M. javanica pre-parasitic juveniles. Both cDNAs have an ORF of 1968 bp for a deduced translation product of 656 amino acid residues. The key residues essential to acetylcholinesterase (AChE) structure and function are conserved in both sequences. M. incognita and M. javanica AChE share a homology of 98.8% at the amino acid level and 97% at the nucleotide level. Phylogenetic analysis showed that Meloidogyne and Caenorhabditis AChE form a cluster among AChE of triploblastic organisms. This Meloidogyne AChE is expressed in eggs, pre-parasitic juveniles and males and AChE activity was detected in situ in amphids of pre-parasitic juveniles. The opportunity of using AChE as a target in new strategies of nematode control is discussed.