Alternative splicing of para-sodium channel α-asubunit genes from diamondback moth strains with different sensitivity to a pyrethroid

Sequence analysis of cDNA clones amplified from para-sodium channel α-subunit transcripts of the diamondback moth, Plutella xylostella L., identified a new optional exon derived from exon 24. Furthermore, mutually exclusive exons 26a and 26b were found to be optionally spliced at low frequency. The occurrence of each alternative exon was examined at different developmental stages using strains showing different sensitivities to a pyrethroid. Results showed that alternative exon usage might be developmentally regulated and divergent among strains. No alternative exon possibly involving pyrethroid resistance was detected.