Life Sciences Commons^™

Changes In Both Trans- And Cis-Regulatory Elements Mediate Insecticide Resistance In A Lepidopteron Pest, Spodoptera Exigua, Bo Hu, He Huang, Songzhu Hu, Miaomiao Ren, Qi Wei, Xiangrui Tian, Mohammed Esmail Abdalla Elzaki, Chris Bass, Jianya Su, Subba Reddy Palli

Entomology Faculty Publications

The evolution of insect resistance to insecticides is frequently associated with overexpression of one or more cytochrome P450 enzyme genes. Although overexpression of CYP450 genes is a well-known mechanism of insecticide resistance, the underlying regulatory mechanisms are poorly understood. Here we uncovered the mechanisms of overexpression of the P450 gene, CYP321A8 in a major pest insect, Spodoptera exigua that is resistant to multiple insecticides. CYP321A8 confers resistance to organophosphate (chlorpyrifos) and pyrethroid (cypermethrin and deltamethrin) insecticides in this insect. Constitutive upregulation of transcription factors CncC/Maf are partially responsible for upregulated expression of CYP321A8 in the resistant strain. Reporter gene assays …

Tomato Chlorosis Virus Infection Facilitates Bemisia Tabaci Med Reproduction By Elevating Vitellogenin Expression, Liping Huang, Xiaobin Shi, Jizhe Shi, Zhuo Zhang, Yong Fang, Zhanhong Zhang, Qiuyi Pan, Limin Zheng, Yang Gao, Deyong Zhang, Xinqiu Tan, Yong Liu, Xuguo Zhou

Entomology Faculty Publications

Transmission of plant pathogenic viruses mostly relies on insect vectors. Plant virus could enhance its transmission by modulating the vector. Previously, we showed that feeding on virus infected plants can promote the reproduction of the sweet potato whitefly, Bemisia tabaci MED (Q biotype). In this study, using a whitefly-Tomato chlorosis virus (ToCV)-tomato system, we investigated how ToCV modulates B. tabaci MED reproduction to facilitate its spread. Here, we hypothesized that ToCV-infected tomato plants would increase B. tabaci MED fecundity via elevated vitellogenin (Vg) gene expression. As a result, fecundity and the relative expression of B. tabaci MED Vg …

Intragenic Dna Methylation Regulates Insect Gene Expression And Reproduction Through The Mbd/Tip60 Complex, Guanfeng Xu, Hao Lyu, Yangqin Yi, Yuling Peng, Qili Feng, Qisheng Song, Chengcheng Gong, Xuezhen Peng, Subba Reddy Palli, Sichun Zheng

Entomology Faculty Publications

DNA methylation is an important epigenetic modification. However, the regulations and functions of insect intragenic DNA methylation remain unknown. Here, we demonstrate that a regulatory mechanism involving intragenic DNA methylation controls ovarian and embryonic developmental processes in Bombyx mori. In B. mori, DNA methylation is found near the transcription start site (TSS) of ovarian genes. By promoter activity analysis, we observed that 5′ UTR methylation enhances gene expression. Moreover, methyl-DNA-binding domain protein 2/3 (MBD2/3) binds to the intragenic methyl-CpG fragment and recruits acetyltransferase Tip60 to promote histone H3K27 acetylation and gene expression. Additionally, genome-wide analyses showed that the peak …

Up-Regulation Of Apoptotic- And Cell Survival-Related Gene Pathways Following Exposures Of Western Corn Rootworm To B. Thuringiensis Crystalline Pesticidal Proteins In Transgenic Maize Roots, Brad S. Coates, Emeline Deleury, Aaron J. Gassmann, Bruce E. Hibbard, Lance Meinke, Nicholas J. Miller, Jennifer L. Petzold-Maxwell, B. Wade French, Thomas W. Sappington, Blair D. Siegfried, Thomas Guillemaud

Department of Entomology: Faculty Publications

Background: Resistance of pest insect species to insecticides, including B. thuringiensis (Bt) pesticidal proteins expressed by transgenic plants, is a threat to global food security. Despite the western corn rootworm, Diabrotica virgifera virgifera, being a major pest of maize and having populations showing increasing levels of resistance to hybrids expressing Bt pesticidal proteins, the cell mechanisms leading to mortality are not fully understood.

Results: Twenty unique RNA-seq libraries from the Bt susceptible D. v. virgifera inbred line Ped12, representing all growth stages and a range of different adult and larval exposures, were assembled into a reference transcriptome. Ten-day exposures …