The role of cuticular hydrocarbons in adaptations to changing climatic conditions and in sexual communication of Anopheles mosquitoes

表皮碳氢化合物在适应气候条件变化和按蚊性交流中的作用

• 批准号: NE/W00402X/1
• 负责人: Olena Riabinina
• 金额: $ 10.69万
• 依托单位: Durham University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FW00402X%2F1
• 关键词: role; cuticular; hydrocarbons; adaptations; changing

Malaria is a vector-borne disease that currently threatens half of the world population. Anopheles mosquitoes transmit malaria, and many tools have been developed to prevent mosquito bites, such as mosquito repellents and insecticide-treated bed nets. Despite the huge reductions in malaria since the millennium, present control methods have stalled, partly due to emerging insecticide resistance in malaria mosquito vectors. In addition, mosquitoes invade new regions of the world, thus increasing the risk of malaria to people. Better understanding of mosquito biology and ecology could lead to the development of novel methods of mosquito vector control.Here we will focus on two species/species complexes of Anopheles mosquitoes, and will study how a class of chemical compounds that is found on their bodies helps mosquitoes to recognize mating partners and to colonize new areas. These compounds are cuticular hydrocarbons, and they form a waxy layer on the mosquito cuticle - their analogue of skin. In other insects, cuticular hydrocarbons are known to have two roles. They prevent water loss - desiccation, which is likely to occur in hot tropical environments where mosquitoes live. They are also used as an attractive perfume for recognizing appropriate mating partners. However, the role of cuticular hydrocarbons in malaria mosquitoes is not well known, and this project sets out to test it.We will focus on the two Anopheles species that we selected because of the special interest that they present.The first species, Anopheles stephensi, are native to India, but have in the past 10 years invaded the Horn of Africa. Upon migration from India, these mosquitoes had to adapt to and survive in dry and hot climate of the Arabian peninsula and East Africa. Thus, any adaptations to different environmental conditions must also be extremely recent and are happening very rapidly. We have a chance now to study this unique biological process as it occurs, and we predict that changes in cuticular hydrocarbons help these mosquitoes in their invasion of Africa. In addition, An.stephensi also have to distinguish their potential mating partners from the native African Anopheles species. This means that their attractive perfumes, if they use them at all, might have been modified - this again brings us to study cuticular hydrocarbons. The second species of interest, Anopheles farauti, inhabits northern Australia, Papua New Guinea, the Solomon islands and Vanuatu. In fact, this is not one species but a complex of 8 closely related species, some of which occur at the same locations, and some live on islands in isolation from their relatives. We so far have studied 1 of the 8 species that inhabits Northern Australia. We found that cuticular hydrocarbons of the males and females of this species are very different. This exciting finding implies that they may indeed use cuticular hydrocarbons as the perfume to select their mates as it has been shown in many other insect species. We now want to extend our study to the other sibling species, and see whether their cuticular hydrocarbons are different between males and females. We predict that they are, but are modified slightly when the relatives of the mosquitoes live at the same location. The finding that An.farauti and/or An.stephensi use chemical compounds to find their mates will have profound implications for other mosquito species and mosquito control strategies. Mosquito genes and proteins, responsible for production and perception of cuticular hydrocarbons, may then be targeted in a variety of ways, leading to novel methods of malaria vector control that we urgently need. In addition, if we find evidence that rapidly changing cuticular hydrocarbons helps mosquitoes adapt to changing climate, this will help the scientists predict how mosquito populations may migrate and invade around the world in the future. This may guide prevention strategies that will save millions of human lives.

疟疾是一种媒介传播的疾病，目前威胁着世界一半人口。按蚊传播疟疾，并且已经开发了许多工具来防止蚊虫叮咬，例如驱蚊剂和经过杀虫剂处理的蚊帐。尽管自本世纪以来疟疾数量大幅减少，但目前的控制方法已经停滞不前，部分原因是疟疾蚊媒中出现了杀虫剂耐药性。此外，蚊子入侵世界新地区，从而增加了人们患疟疾的风险。对蚊子生物学和生态学的更好理解可能会导致蚊子媒介控制新方法的开发。在这里，我们将重点关注按蚊的两个物种/物种复合体，并将研究在其体内发现的一类化合物如何帮助蚊子识别交配伙伴并在新区域定居。这些化合物是角质层碳氢化合物，它们在蚊子角质层（相当于皮肤）上形成蜡层。在其他昆虫中，表皮碳氢化合物有两个作用。它们可以防止水分流失 - 干燥，这很可能发生在蚊子居住的炎热热带环境中。它们还被用作有吸引力的香水，用于识别合适的交配对象。然而，表皮碳氢化合物在疟疾蚊子中的作用尚不清楚，本项目着手对其进行测试。我们将重点关注我们选择的两种按蚊，因为它们具有特殊的意义。第一种按蚊是史氏按蚊，原产于印度，但在过去 10 年入侵了非洲之角。这些蚊子从印度迁徙过来后，必须适应阿拉伯半岛和东非干燥炎热的气候并生存。因此，对不同环境条件的任何适应也必须是最近发生的，并且发生得非常迅速。我们现在有机会研究这种独特的生物过程，我们预测角质层碳氢化合物的变化有助于这些蚊子入侵非洲。此外，史蒂芬按按蚊还必须将其潜在的交配伙伴与非洲本土按蚊物种区分开来。这意味着，如果他们使用的话，他们迷人的香水可能已经被修改过——这再次让我们开始研究角质层碳氢化合物。第二个感兴趣的物种是法劳按按蚊，栖息在澳大利亚北部、巴布亚新几内亚、所罗门群岛和瓦努阿图。事实上，这不是一个物种，而是由 8 个密切相关的物种组成的复合体，其中一些出现在同一地点，一些则生活在与其亲属隔离的岛屿上。到目前为止，我们已经研究了栖息在澳大利亚北部的 8 个物种中的 1 个。我们发现该物种的雄性和雌性的表皮碳氢化合物非常不同。这一令人兴奋的发现意味着它们确实可能使用表皮碳氢化合物作为香水来选择它们的伴侣，正如许多其他昆虫物种所显示的那样。我们现在想将我们的研究扩展到其他兄弟物种，看看它们的雄性和雌性之间的表皮碳氢化合物是否不同。我们预测它们是这样的，但当蚊子的亲戚生活在同一地点时，它们会略有修改。法劳蒂按蚊和/或史蒂芬按蚊使用化学物质寻找配偶的发现将对其他蚊子种类和蚊子控制策略产生深远的影响。负责产生和感知表皮碳氢化合物的蚊子基因和蛋白质可以通过多种方式被靶向，从而产生我们迫切需要的疟疾媒介控制新方法。此外，如果我们找到证据表明快速变化的表皮碳氢化合物有助于蚊子适应不断变化的气候，这将有助于科学家预测蚊子种群未来如何在世界各地迁移和入侵。这可能会指导预防策略，从而挽救数百万人的生命。

项目成果

Genetic Toolbox Approaches in Mosquitoes.

蚊子的遗传工具箱方法。

• DOI: 10.1101/pdb.top107691
• 发表时间: 2022
• 期刊: Cold Spring Harbor protocols
• 作者: Riabinina O