Molecular cloning and life‐stage expression pattern of a new chorismate mutase gene from the root‐knot nematode Meloidogyne arenaria

Abstract

A putative chorismate mutase (CM) gene, Ma‐cm‐1, was isolated from the nematode Meloidogyne arenaria. The predicted protein (named MA‐CM‐1) with amino‐terminal signal peptides was significantly similar to CMs in M. javanica, M. incognita, Globodera pallida and bacteria. Secondary structure prediction of MA‐CM‐1 indicated that it also had the three conserved alpha‐helix domains present in Escherichia coli CMs. RT‐PCR analysis showed that Ma‐cm‐1 was transcribed in both the preparasitic second stage and early postinfection juveniles. In situ mRNA hybridization revealed that the transcripts of Ma‐cm‐1 accumulated specifically in the two subventral oesophageal gland cells of M. arenaria. The widespread existence of CMs in the sedentary endoparasitic nematodes indicates that this enzyme is a key element in the host–parasite interaction.