Disease Vector Group, Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden.
Disease Vector Group, Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden.
Insect Biochem Mol Biol. 2023 Aug;159:103988. doi: 10.1016/j.ibmb.2023.103988. Epub 2023 Jul 11.
Mosquitoes rely mainly on the sense of smell to decipher their environment and locate suitable food sources, hosts for blood feeding and oviposition sites. The molecular bases of olfaction involve multigenic families of olfactory proteins that have evolved to interact with a narrow set of odorants that are critical for survival. Understanding the complex interplay between diversified repertoires of olfactory proteins and ecologically-relevant odorant signals, which elicit important behaviors, is fundamental for the design of novel control strategies targeting the sense of smell of disease vector mosquitoes. Previously, large multigene families of odorant receptor and ionotropic receptor proteins, as well as a subset of odorant-binding proteins have been shown to mediate the selectivity and sensitivity of the mosquito olfactory system. In this study, we identify a mosquito-specific antennal protein (MSAP) gene as a novel molecular actor of odorant reception. MSAP is highly conserved across mosquito species and is transcribed at an extremely high level in female antennae. In order to understand its role in the mosquito olfactory system, we generated knockout mutant lines in Anopheles gambiae, and performed comparative analysis of behavioral and physiological responses to human-associated odorants. We found that MSAP promotes female mosquito attraction to human odor and enhances the sensitivity of the antennae to a variety of odorants. These findings suggest that MSAP is an important component of the mosquito olfactory system, which until now has gone completely unnoticed.
蚊子主要依靠嗅觉来破译环境信息，定位合适的食物源、吸血宿主和产卵地。嗅觉的分子基础涉及多基因家族的嗅觉蛋白，这些蛋白已经进化到可以与一组关键生存的狭窄气味物质相互作用。理解嗅觉蛋白多样化的表达谱与生态相关气味信号之间的复杂相互作用，这些气味信号可以引发重要的行为，对于设计针对病媒蚊子嗅觉的新型控制策略至关重要。先前已经表明，大量的气味受体和离子型受体蛋白的多基因家族，以及一部分气味结合蛋白，介导了蚊子嗅觉系统的选择性和敏感性。在这项研究中，我们鉴定出一种蚊子特异性触角蛋白（MSAP）基因，作为气味接收的新型分子作用因子。MSAP在蚊子物种中高度保守，在雌性触角中转录水平极高。为了了解它在蚊子嗅觉系统中的作用，我们在冈比亚按蚊中生成了敲除突变株，并对其对人类相关气味的行为和生理反应进行了比较分析。我们发现 MSAP 促进了雌性蚊子对人类气味的吸引力，并增强了触角对各种气味的敏感性。这些发现表明，MSAP 是蚊子嗅觉系统的一个重要组成部分，而这个系统到目前为止一直被忽视。
