Vector Behaviour and Pathogen Interaction Group, Instituto René Rachou - FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil.
Laboratorio de Insectos Sociales, Instituto de Fisiología, Biología Molecular y Neurociencias, Universidad de Buenos Aires - CONICET, Buenos Aires, Argentina.
PLoS One. 2023 Mar 3;18(3):e0282490. doi: 10.1371/journal.pone.0282490. eCollection 2023.
Rhodnius prolixus is a vector of Chagas disease and has become a model organism to study physiology, behavior, and pathogen interaction. The publication of its genome allowed initiating a process of comparative characterization of the gene expression profiles of diverse organs exposed to varying conditions. Brain processes control the expression of behavior and, as such, mediate immediate adjustment to a changing environment, allowing organisms to maximize their chances to survive and reproduce. The expression of fundamental behavioral processes like feeding requires fine control in triatomines because they obtain their blood meals from potential predators. Therefore, the characterization of gene expression profiles of key components modulating behavior in brain processes, like those of neuropeptide precursors and their receptors, seems fundamental. Here we study global gene expression profiles in the brain of starved R. prolixus fifth instar nymphs by means of RNA sequencing (RNA-Seq).
The expression of neuromodulatory genes such as those of precursors of neuropeptides, neurohormones, and their receptors; as well as the enzymes involved in the biosynthesis and processing of neuropeptides and biogenic amines were fully characterized. Other important gene targets such as neurotransmitter receptors, nuclear receptors, clock genes, sensory receptors, and takeouts genes were identified and their gene expression analyzed.
We propose that the set of neuromodulatory-related genes highly expressed in the brain of starved R. prolixus nymphs deserves functional characterization to allow the subsequent development of tools targeting them for bug control. As the brain is a complex structure that presents functionally specialized areas, future studies should focus on characterizing gene expression profiles in target areas, e.g. mushroom bodies, to complement our current knowledge.
Rhodnius prolixus 是恰加斯病的传播媒介，已成为研究生理、行为和病原体相互作用的模式生物。其基因组的公布使得对不同器官在不同条件下的基因表达谱进行比较特征分析成为可能。大脑过程控制着行为的表达，因此，介导对不断变化的环境的即时调整，使生物体最大限度地提高生存和繁殖的机会。像摄食这样的基本行为过程的表达需要在三锥虫中进行精细控制，因为它们从潜在的捕食者那里获取血液餐。因此，对调节大脑过程中行为的关键成分的基因表达谱的特征描述，如神经肽前体及其受体的基因表达谱，似乎是至关重要的。在这里，我们通过 RNA 测序（RNA-Seq）研究了饥饿的 R. prolixus 五龄若虫大脑中的全基因表达谱。
神经调质基因的表达，如神经肽前体、神经激素及其受体的表达；以及参与神经肽和生物胺生物合成和加工的酶也得到了充分的描述。还鉴定了其他重要的基因靶点，如神经递质受体、核受体、生物钟基因、感觉受体和摄取基因，并分析了它们的基因表达。
我们提出，在饥饿的 R. prolixus 若虫大脑中高度表达的一组与神经调质相关的基因值得进行功能特征描述，以便随后开发针对这些基因的控制虫子的工具。由于大脑是一个具有功能特化区域的复杂结构，未来的研究应该集中在对目标区域（如蘑菇体）的基因表达谱进行特征描述，以补充我们目前的知识。
