Genomic organization of the para‐sodium channel α‐subunit genes from the pyrethroid‐resistant and ‐susceptible strains of the diamondback moth

Abstract

We examined the genomic organization of the para-sodium channel alpha-subunit gene of the diamondback moth, Plutella xylostella (L.). The nucleotide sequence contained 34 putative exons, which covered almost the entire coding region of the gene producing 1,889 amino acid residues. Deduced amino acid identity to the hscp locus of Heliothis virescens was 84%. Comparison of deduced amino acid sequences of the permethrin-resistant and -susceptible strains showed two substitutions other than kdr and super-kdr-like substitutions. They were Ala to Thr (A1060T) and Pro to Ser (P1836S) at the linker region of the domains II-III and the carboxyl terminus, respectively. Furthermore, we developed PCR amplification protocols for the rapid detection of both substitutions.

Molecular characterization of a sodium channel gene from the Silkworm Bombyx mori

“…The exons of other species were obtained by Blast search of their genome Databases (http://www.ncbi.nlm.nih.gov/sutils/genom_table.cgi?organism¼insects). homologue, exon 21, is found in the Plutella xylostella sodium channel gene (Sonoda et al, 2008). Similar to exon 21 in P. xylostella, the 5 0 portion of exon 22, named 22i, is optional.…”

“…An exon 22 (Dong, 1997); Pediculus humanus, AY191155 (Tomita et al, 2003); Drosophila melanogaster: M32078 (Loughney et al, 1989;Thackeray and Ganetzky, 1995); Musca domestica, X96668 (Knipple et al, 1994;Lee et al, 2002); Plutella xylostella (not available) (Sonoda et al, 2008); Heliothis virescens, AF072493 (Park et al, 1999). The exons of other species were obtained by Blast search of their genome Databases (http://www.ncbi.nlm.nih.gov/sutils/genom_table.cgi?organism¼insects).…”

Alternative splicing of para-sodium channel .ALPHA.-subunit genes from diamondback moth strains with different sensitivity to a pyrethroid

“…Exons 26a and 26b, corresponding to exons k and l in M. domestica 13) and exons G2 and G1 in B. germanica, 14) were reported to be mutually exclusive exons. 10) On the other hand, exon 3, corresponding to exon 26a or 26b, was optional in the varroa mite, Varroa destructor. 16) Exon 26b was present at high frequencies in all developmental stages of both strains.…”

“…8) In a previous study, the genomic and cDNA sequences encoding the para-sodium a-subunit gene of P. xylostella were examined and alternative splicing at seven sites involving five optional exons and four mutually exclusive exons 9,10) was identified. Reportedly, alternative splicing is a key mechanism for generating a structurally and functionally divergent family of a-subunit transcripts in D. melanogaster and D. virilis.…”

The Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) voltage-gated sodium channel and mutations associated with pyrethroid resistance in field-collected adult males

“…2, residues 1099 to 1121 of para); however, the amino acid sequence of GLKAALCGRCVSSE was commonly found in this location among the clones analyzed from the different H. zea specimens examined (not shown). This 14 amino acid sequence is identical to the B. mori internally optional spliced exon 22 (Shao et al, 2009) and only the last residue E differs from the one present in the Plutella xylostella L sodium channel (Sonoda et al, 2008). It is possible that this splice variant may also occur in H. virescens, but just was not identified in the transcripts examined by Park et al (1999).…”