Xu Qiang, Wang Haichuan, Zhang Lee, Liu Nannan
Department of Entomology and Plant Pathology, Auburn University, Auburn, AL 36849, USA.
Biochem Biophys Res Commun. 2006 Jun 30;345(2):774-80. doi: 10.1016/j.bbrc.2006.04.155. Epub 2006 May 4.
The loss of target site sensitivity to insecticides resulting from a substitution of leucine to phenylalanine, termed the kdr mutation, in the voltage-gated sodium channel of the insect nervous system is known to be important in insecticide resistance. However, little is known about the molecular basis of the genotype and kdr-mediated resistance phenotype relationship. This study investigated whether the functional polymorphism of the L-to-F kdr mutation that determines resistance phenotype undergoes DNA variation or goes through transcriptional regulatory variation. We detected no correlation for the kdr allele at the genomic DNA level with levels of susceptibility and resistance to insecticide. However, we find a strong correlation between the kdr allelic expression and levels of insecticide resistance and susceptibility through RNA allelic variation and RNA editing. These findings shed new light on the role of transcriptional regulation in the kdr-mediated resistance in mosquitoes and its connection with the genotype-resistance phenotype relationship.
在昆虫神经系统的电压门控钠通道中，由于亮氨酸被苯丙氨酸取代而导致对杀虫剂的靶标位点敏感性丧失，即所谓的击倒抗性（kdr）突变，已知其在抗药性中起重要作用。然而，关于基因型与kdr介导的抗性表型关系的分子基础知之甚少。本研究调查了决定抗性表型的L-to-F kdr突变的功能多态性是发生DNA变异还是经历转录调控变异。我们在基因组DNA水平上未检测到kdr等位基因与杀虫剂敏感性和抗性水平之间的相关性。然而，通过RNA等位基因变异和RNA编辑，我们发现kdr等位基因表达与杀虫剂抗性和敏感性水平之间存在很强的相关性。这些发现为转录调控在蚊子kdr介导的抗性中的作用及其与基因型-抗性表型关系之间的联系提供了新的线索。
