Laboratório de Biologia Molecular de Insetos, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil.
1. Entomology and Nematology Department, Citrus Research and Education Center, University of Florida, Lake Alfred, FL, USA.
J Biol Rhythms. 2018 Jun;33(3):272-288. doi: 10.1177/0748730418772175.
Most organisms feature an endogenous circadian clock capable of synchronization with their environment. The most well-known synchronizing agents are light and temperature. The circadian clock of mosquitoes, vectors of many pathogens, drives important behaviors related to vectoral capacity, including oviposition, host seeking, and hematophagy. Main clock gene expression, as well as locomotor activity patterns, has been identified in Aedes aegypti and Culex quinquefasciatus under artificial light-dark cycles. Given that these mosquito species thrive in tropical areas, it is reasonable to speculate that temperature plays an important role in the circadian clock. Here, we provide data supporting a different hierarchy of light and temperature as zeitgebers of two mosquito species. We recorded their locomotor activity and quantified mRNA expression of the main clock genes in several combinations of light and temperature cycles. We observed that A. aegypti is more sensitive to temperature, while C. quinquefasciatus is more responsive to light. These variations in clock gene expression and locomotor activity may have affected the mosquito species' metabolism, energy expenditure, fitness cost, and pathogen transmission efficiency. Our findings are relevant to chronobiology studies and also have epidemiological implications.
大多数生物都具有内源性生物钟，能够与环境同步。最著名的同步因子是光和温度。蚊子的生物钟是许多病原体的传播媒介，它驱动着与传播能力相关的重要行为，包括产卵、寻找宿主和吸血。在人工光照-黑暗周期下，已经确定了埃及伊蚊和致倦库蚊的主要时钟基因表达和运动活动模式。鉴于这些蚊子物种在热带地区繁衍生息，因此可以合理推测温度在生物钟中起着重要作用。在这里，我们提供的数据支持两种蚊子物种的光和温度作为时间信号的不同层次。我们记录了它们的运动活动，并在不同的光和温度周期组合下量化了主要时钟基因的 mRNA 表达。我们观察到埃及伊蚊对温度更敏感，而致倦库蚊对光更敏感。这些时钟基因表达和运动活动的变化可能会影响蚊子物种的新陈代谢、能量消耗、适应成本和病原体传播效率。我们的研究结果与时间生物学研究相关，也具有流行病学意义。
