Menon Rohan, Ignell Rickard, Hill Sharon R
Unit of Chemical Ecology, Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden.
Max Planck Center next Generation Insect Chemical Ecology, Alnarp, Sweden.
Parasit Vectors. 2025 Sep 23;18(1):372. doi: 10.1186/s13071-025-07028-y.
The northern house mosquito, Culex pipiens, is a noted arboviral disease vector commonly found throughout Europe and North America. Two morphologically identical biotypes of this species, Culex pipiens pipiens and Culex pipiens molestus, display differential host preference to birds and humans, respectively; however, little is known about the genetic mechanisms regulating this behavior.
Using a Y-tube olfactometer, the host preference of the host-seeking female mosquitoes of both biotypes was tested by providing a choice between synthetic chicken and human odor blends, across 2 days of testing. Antennal transcriptomes, from the mosquitoes that demonstrated a clear and consistent preference to either of the odor blends, were created to observe differences in antennal chemosensory gene expression.
In the host preference experiments, Cx. pipiens pipiens and Cx. pipiens molestus demonstrated a weak, but significant, preference to the synthetic chicken and human odor blends, respectively, when tested across multiple days. The transcriptome created from the antennae of mosquitoes that made a consistent choice over 2 days of testing identified 9 odorant receptors, 3 ionotropic receptors, and 12 odorant binding proteins, and other chemosensory genes, that were differentially expressed between the two biotypes, which correlate with the observed differential host preference.
This study identified a set of chemosensory genes that are putatively correlated with the differential host preference of the two biotypes. Future research is required to increase the understanding of the function of the identified chemosensory receptors, and how they can be used as genetic markers of host preference of wild mosquitoes.
北方家蚊（库蚊）是一种著名的虫媒病毒病媒介，常见于欧洲和北美各地。该物种的两种形态相同的生物型，即致倦库蚊和骚扰库蚊，分别对鸟类和人类表现出不同的宿主偏好；然而，关于调节这种行为的遗传机制知之甚少。
使用Y型嗅觉仪，在两天的测试中，通过在合成鸡气味混合物和人类气味混合物之间提供选择，测试了两种生物型的寻找宿主的雌性蚊子的宿主偏好。对表现出对任一气味混合物有明确且一致偏好的蚊子的触角进行转录组分析，以观察触角化学感应基因表达的差异。
在宿主偏好实验中，致倦库蚊和骚扰库蚊在多天测试时，分别对合成鸡气味混合物和人类气味混合物表现出微弱但显著的偏好。从在两天测试中做出一致选择的蚊子触角创建的转录组鉴定出9种气味受体、3种离子型受体和12种气味结合蛋白以及其他化学感应基因，这些基因在两种生物型之间差异表达，这与观察到的不同宿主偏好相关。
本研究确定了一组可能与两种生物型不同宿主偏好相关的化学感应基因。需要进一步研究以增进对已鉴定化学感应受体功能的理解，以及它们如何用作野生蚊子宿主偏好的遗传标记。
