中国农业科学院农业基因组研究所萧玉涛课题组揭示二化螟局部适应的极端遗传特征。2024年8月1日，《国家科学评论》杂志在线发表了这项成果。

研究人员表示，气候变化是驱动遗传分化和适应性性状进化的重要因素。二化螟（Chilo suppressalis）是一种对水稻生产造成严重危害的害虫。然而，缺乏自然种群基因组学数据阻碍了对其气候适应性的深入理解，特别是适应性性状的遗传基础。

为了解决这一问题，研究人员采用384只个体的全基因组重测序数据，探讨了C. suppressalis在中国的种群结构、种群历史和基因流动。研究观察到其基因流动呈不对称性，从中心种群向边缘种群迁移。

通过全基因组选择扫描和基因型-环境关联研究，研究人员识别出了可能与气候适应相关的潜在位点。其中，最显著的信号与冷耐性相关，涉及一个同源盒基因——goosecoid（GSC），其在低纬度和高纬度的表达水平显著不同。此外，通过RNA干扰下调该基因的表达增强了其冷耐性表型。该研究揭示了C. suppressalis适应环境的遗传基础，这对确保新型控制技术的持续有效性和可持续性至关重要。

附：英文原文

Title: Extreme genetic signatures of local adaptation in a notorious rice pest, Chilo suppressalis

Author: Peng, Yan, Mao, Kaikai, Li, Hongran, Ping, Junfen, Zhu, Jingyun, Liu, Xinye, Zhang, Zhuting, Jin, Minghui, Wu, Chao, Wang, Nan, Yesaya, Alexander, Wilson, Kenneth, Xiao, Yutao

Issue&Volume: 2024-08-01

Abstract: Climatic variation stands as a significant driving force behind genetic differentiation and the evolution of adaptive traits. Chilo (C.) suppressalis, commonly known as the rice stem borer, is a highly destructive pest that crucially harms rice production. The lack of natural population genomics data has hindered a more thorough understanding of its climate adaptation, particularly the genetic basis underlying adaptive traits. To overcome this obstacle, our study employed completely resequenced genomes of 384 individuals to explore the population structure, demographic history, and gene flow of C. suppressalis in China. This study observed that its gene flow occurred asymmetrically, moving from central populations to peripheral populations. Using genome-wide selection scans and genotype-environment association studies, we identified potential loci that may be associated with climatic adaptation. The most robust signal was found to be associated with cold tolerance, linked to a homeobox gene, goosecoid (GSC), whose expression level was significantly different in low and high latitudes. Moreover, downregulating the expression of this gene by RNAi enhances its cold tolerance phenotypes. Our findings have uncovered and delved into the genetic foundation of the ability of C. suppressalis to adapt to its environment. This is essential in ensuring the continued effectiveness and sustainability of novel control techniques.

DOI: 10.1093/nsr/nwae221

Source: https://dx.doi.org/10.1093/nsr/nwae221