Department of Entomology, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China.
The State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.
BMC Genomics. 2020 Sep 14;21(1):634. doi: 10.1186/s12864-020-07051-6.
Chilo suppressalis is a widespread rice pest that poses a major threat to food security in China. This pest can develop resistance to Cry toxins from Bacillus thuringiensis (Bt), threatening the sustainable use of insect-resistant transgenic Bt rice. However, the molecular basis for the resistance mechanisms of C. suppressalis to Cry1C toxin remains unknown. This study aimed to identify genes associated with the mechanism of Cry1C resistance in C. suppressalis by comparing the midgut transcriptomic responses of resistant and susceptible C. suppressalis strains to Cry1C toxin and to provide information for insect resistance management.
A C. suppressalis midgut transcriptome of 139,206 unigenes was de novo assembled from 373 million Illumina HiSeq and Roche 454 clean reads. Comparative analysis identified 5328 significantly differentially expressed unigenes (DEGs) between C. suppressalis Cry1C-resistant and -susceptible strains. DEGs encoding Bt Cry toxin receptors, aminopeptidase-P like protein, the ABC subfamily and alkaline phosphatase were downregulated, suggesting an association with C. suppressalis Cry1C resistance. Additionally, Cry1C resistance in C. suppressalis may be related to changes in the transcription levels of enzymes involved in hydrolysis, digestive, catalytic and detoxification processes.
Our study identified genes potentially involved in Cry1C resistance in C. suppressalis by comparative transcriptome analysis. The assembled and annotated transcriptome data provide valuable genomic resources for further study of the molecular mechanisms of C. suppressalis resistance to Cry toxins.
二化螟是一种广泛分布的水稻害虫，对中国的粮食安全构成重大威胁。这种害虫对苏云金芽孢杆菌（Bt）的 Cry 毒素具有抗药性，威胁到抗虫转基因 Bt 水稻的可持续使用。然而，二化螟对 Cry1C 毒素的抗性机制的分子基础尚不清楚。本研究旨在通过比较 Cry1C 毒素抗性和敏感二化螟品系的中肠转录组应答，鉴定与 Cry1C 抗性机制相关的基因，为昆虫抗性管理提供信息。
从 3.73 亿个 Illumina HiSeq 和 Roche 454 清洁读取中从头组装了 139,206 个二化螟中肠转录本的 de novo 组装。比较分析鉴定了 5328 个在二化螟 Cry1C 抗性和敏感品系之间显著差异表达的 unigenes（DEGs）。编码 Bt Cry 毒素受体、氨肽酶-P 样蛋白、ABC 亚家族和碱性磷酸酶的 DEGs 下调，表明与二化螟 Cry1C 抗性有关。此外，二化螟对 Cry1C 的抗性可能与水解、消化、催化和解毒过程中涉及的酶的转录水平变化有关。
通过比较转录组分析，我们鉴定了与二化螟 Cry1C 抗性相关的潜在基因。组装和注释的转录组数据为进一步研究二化螟对 Cry 毒素的抗性分子机制提供了有价值的基因组资源。
