Microbiology Commons^™

Mapk-Mediated Transcription Factor Gatad Contributes To Cry1ac Resistance In Diamondback Moth By Reducing Pxmalp Expression, Le Guo, Zhouqiang Cheng, Jianying Qin, Dan Sun, Shaoli Wang, Qingjun Wu, Neil Crickmore, Xuguo Zhou, Alejandra Bravo, Mario Soberón, Zhaojiang Guo, Youjun Zhang

Entomology Faculty Publications

The benefits of biopesticides and transgenic crops based on the insecticidal Cry-toxins from Bacillus thuringiensis (Bt) are considerably threatened by insect resistance evolution, thus, deciphering the molecular mechanisms underlying insect resistance to Bt products is of great significance to their sustainable utilization. Previously, we have demonstrated that the down-regulation of PxmALP in a strain of Plutella xylostella (L.) highly resistant to the Bt Cry1Ac toxin was due to a hormone-activated MAPK signaling pathway and contributed to the resistance phenotype. However, the underlying transcriptional regulatory mechanism remains enigmatic. Here, we report that the PxGATAd transcription factor (TF) is responsible for the …

The Regulation Landscape Of Mapk Signaling Cascade For Thwarting Bacillus Thuringiensis Infection In An Insect Host, Zhaojiang Guo, Shi Kang, Qingjun Wu, Shaoli Wang, Neil Crickmore, Xuguo Zhou, Alejandra Bravo, Mario Soberón, Youjun Zhang

Entomology Faculty Publications

Host-pathogen interactions are central components of ecological networks where the MAPK signaling pathways act as central hubs of these complex interactions. We have previously shown that an insect hormone modulated MAPK signaling cascade participates as a general switch to trans-regulate differential expression of diverse midgut genes in the diamondback moth, Plutella xylostella (L.) to cope with the insecticidal action of Cry1Ac toxin, produced by the entomopathogenic bacterium Bacillus thuringiensis (Bt). The relationship between topology and functions of this four-tiered phosphorylation signaling cascade, however, is an uncharted territory. Here, we carried out a genome-wide characterization of all the MAPK orthologs …

Plants Pre-Infested With Viruliferous Med/Q Cryptic Species Promotes Subsequent Bemisia Tabaci Infestation, Xiaobin Shi, Gong Chen, Huipeng Pan, Wen Xie, Qingjun Wu, Shaoli Wang, Yong Liu, Xuguo Zhou, Youjun Zhang

Entomology Faculty Publications

The sweet potato whitefly, Bemisia tabaci, is one of the most invasive insect pests worldwide. The two most destructive whitefly cryptic species are MEAM1/B and MED/Q. Given that MED/Q has replaced MEAM1/B in China and the invasion of MED/Q has coincided with the outbreak of tomato yellow leaf curl virus (TYLCV), we hypothesize that pre-infestation with viruliferous B. tabaci will affect the subsequent host preferences. To test this hypothesis, we (1) conducted bioassays to compare the host preference of viruliferous and non-viruliferous MEAM1/B and MED/Q, respectively, on plants pre-infested with viruliferous and non-viruliferous MEAM1/B and MED/Q; (2) profiled plant …

Cloning And Characterization Of A Pyrethroid Pesticide Decomposing Esterase Gene, Est3385, From Rhodopseudomonas Palustris Psb-S, Xiangwen Luo, Deyong Zhang, Xuguo Zhou, Jiao Du, Songbai Zhang, Yong Liu

Entomology Faculty Publications

Full length open reading frame of pyrethroid detoxification gene, Est3385, contains 963 nucleotides. This gene was identified and cloned based on the genome sequence of Rhodopseudomonas palustris PSB-S available at the GneBank. The predicted amino acid sequence of Est3385 shared moderate identities (30–46%) with the known homologous esterases. Phylogenetic analysis revealed that Est3385 was a member in the esterase family I. Recombinant Est3385 was heterologous expressed in E. coli, purified and characterized for its substrate specificity, kinetics and stability under various conditions. The optimal temperature and pH for Est3385 were 35 °C and 6.0, respectively. This enzyme could …

Detection And Epidemic Dynamic Of Tocv And Ccyv With Bemisia Tabaci And Weed In Hainan Of China, Xin Tang, Xiaobin Shi, Deyong Zhang, Fan Li, Fei Yan, Youjun Zhang, Yong Liu, Xuguo Zhou

Entomology Faculty Publications

Background: In recent years, two of the crinivirus, Tomato chlorosis virus (ToCV) and Cucurbit chlorotic yellows virus (CCYV) have gained increasing attention due to their rapid spread and devastating impacts on vegetable production worldwide. Both of these viruses are transmitted by the sweet potato whitefly, Bemisia tabaci (Gennadius), in a semi-persistent manner. Up to now, there is still lack of report in Hainan, the south of China.

Methods: We used observational and experimental methods to explore the prevalence and incidence dynamic of CCYV and ToCV transmitted by whiteflies in Hainan of China.

Results: In 2016, the chlorosis symptom was observed …