Modulation of expression at the level of splicing of cut-1 RNA in the infective second-stage juvenile of the plant parasitic nematode Meloidogyne artiellia

The cut-1 gene coding for cuticlin-1 has been isolated from the plant parasitic nematode Meloidogyne artiellia. The sequence of the cut-1 gene was compared with the corresponding sequence from the free-living nematode Caenorhabditis elegans. The high degree of similarity between the amino acid sequences, together with the occurrence of characteristic sequence motifs, indicates that the cuticlin-1 is a non-collagenous component of the cuticle also in plant parasitic nematodes. Studies on the expression pattern during the development of M. artiellia indicate that there is a burst of expression of this gene during moulting. Then, the expression rate is reduced in the infective juveniles, which migrate in the soil. In the sedentary females, in contrast, no expression is detected, while in the males which move freely through the soil, the gene is expressed and the transcript fully processed. These data strongly suggest that the gene is developmentally regulated. It is proposed that the production of cuticlin plays an important role in determining the mechanical properties of the cuticle. Furthermore, evidence is provided to indicate that the modulation of cut-1 expression is achieved by regulation of the cis-splicing mechanism in the infective second-stage juvenile.