UDP-Glycosyltransferases UGT350C3 and UGT344L7 Confer Tolerance to Neonicotinoids in Field Populations of Aphis gossypii.

The cotton aphid, Aphis gossypii, is a polyphagous pest that stunts host plant growth via direct feeding or transmitting plant virus. Due to the long-term application of insecticides, A. gossypii has developed different levels of resistance to numerous insecticides. We found that five field populations had evolved multiple resistances to neonicotinoids. To explore the resistance mechanism mediated by uridine diphosphate glycosyltransferases (UGTs), two upregulated UGT genes in these five strains, UGT350C3 and UGT344L7, were selected for functional analysis of their roles in neonicotinoid detoxification. Transgenic Drosophila bioassay results indicated that compared with the control lines, the UGT350C3 and UGT344L7 overexpression lines were more tolerant to thiamethoxam, imidacloprid, and dinotefuran. Knockdown of UGT350C3 and UGT344L7 significantly increased A. gossypii sensitivity to thiamethoxam, imidacloprid, and dinotefuran. Molecular docking analysis demonstrated that these neonicotinoids could bind to the active pockets of UGT350C3 and UGT344L7. This study provides functional evidence of neonicotinoid detoxification mediated by UGTs and will facilitate further work to identify strategies for preventing the development of neonicotinoid resistance in insects.

Bowen's disease of the vulva and perianal area in a SLE patient successfully treated with Photodynamic therapy: A case report.

Photodynamic therapy (PDT) has emerged as a non-invasive treatment modality for superficial skin cancers. It has the advantage of greater tolerance and providing better cosmetic outcomes than conventional treatment methods. Because of the rarity of extensive Bowen's disease located in the genital area, evidence of efficacy for therapies is mainly based on case reports and clinical experience. This report presents a case of a 32-year-old female with Bowen's disease of the vulva and perianal area with systemic lupus erythematosus successfully treated by 5-aminolaevulinic acid PDT. There was no evidence of recurrence after five-years of follow-up.

Inducible Cytochrome P450s in the Fat Body and Malpighian Tubules of the Polyphagous Pests of Spodoptera litura Confer Xenobiotic Tolerance.

Cytochrome P450 plays vital roles in detoxifying xenobiotics. In this study, SlCYP340A and SlCYP340L expression in the Spodoptera litura fat body and SlCYP332A1, SlCYP6AB12, SlCYP6AB58, SlCYP6AB59, and SlCYP6AN4 expression in the Malpighian tubules were significantly upregulated after cyantraniliprole exposure, and SlCYP6AB58 and SlCYP6AB59 expression levels were simultaneously increased in the Malpighian tubules after gossypol treatment. Drosophila ectopically expressing candidate P450 genes showed that SlCYP332A1, SlCYP6AB12, SlCYP6AB59, SlCYP6AN4, and SlCYP340A conferred cyantraniliprole tolerance. The overexpression of SlCYP6AB58 and SlCYP6AB59 in Drosophila increased the number of eggs laid under the gossypol treatment. Moreover, the knockdown of SlCYP332A1, SlCYP6AB12, SlCYP6AB59, SlCYP6AN4, and SlCYP340A increased S. litura mortality under the cyantraniliprole treatment. Homology modeling and molecular docking results suggested that candidate P450 has the potential to bind with cyantraniliprole. These results indicate that the CYP3 and CYP4 genes participate in cyantraniliprole detoxification and that SlCYP6AB59 may be simultaneously involved in the gossypol tolerance of S. litura.

Inducible Gut-Specific Carboxylesterase SlCOE030 in Polyphagous Pests of Spodoptera litura Conferring Tolerance between Nicotine and Cyantraniliprole.

Insecticides tolerance in herbivorous arthropods is associated with preadaptation to host plant allelochemicals. However, how plant secondary metabolites activate detoxifying metabolic genes to develop tolerance remains unclear. Herein, the tolerance of Spodoptera litura larvae to cyantraniliprole was increased after nicotine exposure. An S. litura α esterase, SlCOE030, was predominantly expressed in the midgut and induced after exposure to cyantraniliprole, nicotine, and cyantraniliprole plus nicotine. Drosophila melanogaster with ectopically overexpressed SlCOE030 enhanced cyantraniliprole and nicotine tolerance by 4.91- and 2.12-fold, respectively. Compared to UAS-SlCOE030 and Esg-GAL4 lines, the Esg > SlCOE030 line laid more eggs after nicotine exposure. SlCOE030 knockdown decreased the sensitivity of nicotine-treated S. litura larvae to cyantraniliprole. Metabolism assays indicated that recombinant SlCOE030 protein metabolizes cyantraniliprole. Homology modeling and molecular docking analysis demonstrated that SlCOE030 exhibits effective affinities for cyantraniliprole and nicotine. Thus, insect CarEs may result in the development of cross-tolerance between synthetic insecticides and plant secondary metabolites.

Functional Inquiry into ATP-Binding Cassette Transporter Genes Contributing to Spirotetramat Resistance in Aphis gossypii Glover.

ATP-binding cassette (ABC) transporters regulate the efflux of a broad spectrum of substrates to extracellular transporting, which play an important role in the detoxification process in arthropods. Here, we described a comprehensive approach to explore the involvement of ABC transporters in spirotetramat resistance in cotton aphids. In this study, synergism bioassays showed 17.05% and 35.42% increases in the toxicity to spirotetramat with the ABC inhibitor verapamil in adult and 3rd instar nymph aphids of the SR strain, respectively. In a competitive assay based on the microinjection of a fluorescent ABC transporter substrate, verapamil (a general ABC inhibitor) and spirotetramat significantly inhibited the elimination of Texas Red. Based on transcriptome data of midguts of spirotetramat-susceptible (SS) and -resistant (SR) strains, the expression levels of ABCB4, ABCB5, ABCF2, MRP11, and MRP12 were significantly upregulated in the SR strain midgut compared to that of the SS strain. Gene functional analysis based on ectopic expression and RNA interference (RNAi) proved that ABCB4, ABCB5, ABCF2, MRP11, and MRP12 were involved in the tolerance of cotton aphids to spirotetramat. Moreover, the upregulated ABCF2, ABCB4, and ABCB5 in the midgut of the SR strain contributed more to the resistance of spirotetramat in in vitro functional analysis. In summary, these results demonstrate that candidate ABC transporter genes in the midgut tissue were involved in spirotetramat resistance, which will help reveal the relationship between ABC transporters and the development of spirotetramat resistance in field populations.

The dynamic structure of Spitzenkörpers of Trichosporon asahii examined by the fluorescent probe FM4-64

Abstract The Spitzenkörper is a dynamic and specialized multicomponent cell complex present in the tips of hyphal cells. The amphiphilic styryl dye FM4-64 was found to be ideal for imaging the dynamic changes of the apical vesicle cluster within growing hyphal tips. It is widely used as a marker of endocytosis and to visualize vacuolar membranes. Here we performed uptake experiments using FM4-64 to study the dynamic of the Spitzenkörper in Trichosporon asahii. We observed that Spitzenkörpers were present at the tip of the budding site of the spore, blastospore, and the germ tube of T. asahii. We also found that Spitzenkörpers were present at the tip of the hyphae as well as the subapical regions. Cytochalasin D, an inhibitor of actin polymerization, leads to abnormal Spitzenkörper formation and loss of cell polarity.