A polygalacturonase of animal origin isolated from the root-knot nematodeMeloidogyne incognita1

The first animal polygalacturonase (PG, EC 2.1.15) encoding cDNA, Mi-pg-1, was cloned from the plant parasitic nematode Meloidogyne incognita. The enzymatic activity of MI-PG-1 was confirmed after heterologous expression in Escherichia coli. The presence of a predicted signal peptide on the MI-PG-1 sequence together with the specific localization of the transcripts of the Mi-pg-1 gene in the oesophageal glands of infective juveniles imply that MI-PG-1 could be secreted into plant tissues. The potential role of MI-PG-1 in parasitism is discussed.