Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil.
Departamento de Bioquímica, Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil.
PLoS Negl Trop Dis. 2021 Jan 6;15(1):e0008915. doi: 10.1371/journal.pntd.0008915. eCollection 2021 Jan.
The adult females of Aedes aegypti mosquitoes are facultative hematophagous insects but they are unable to feed on blood right after pupae emergence. The maturation process that takes place during the first post-emergence days, hereafter named hematophagic and gonotrophic capacitation, comprises a set of molecular and physiological changes that prepare the females for the first gonotrophic cycle. Notwithstanding, the molecular bases underlying mosquito hematophagic and gonotrophic capacitation remain obscure. Here, we investigated the molecular and biochemical changes in adult Ae. aegypti along the first four days post-emergence, prior to a blood meal. We performed a RNA-Seq analysis of the head and body, comparing male and female gene expression time courses. A total of 811 and 203 genes were differentially expressed, respectively in the body and head, and both body parts showed early, mid, and late female-specific expression profiles. Female-specific up-regulation of genes involved in muscle development and the oxidative phosphorylation pathway were remarkable features observed in the head. Functional assessment of mitochondrial oxygen consumption in heads showed a gradual increase in respiratory capacity and ATP-linked respiration as a consequence of induced mitochondrial biogenesis and content over time. This pattern strongly suggests that boosting oxidative phosphorylation in heads is a required step towards blood sucking habit. Several salivary gland genes, proteases, and genes involved in DNA replication and repair, ribosome biogenesis, and juvenile hormone signaling were up-regulated specifically in the female body, which may reflect the gonotrophic capacitation. This comprehensive description of molecular and biochemical mechanisms of the hematophagic and gonotrophic capacitation in mosquitoes unravels potentially new targets for vector control.
成蚊的埃及伊蚊雌蚊是兼性血食昆虫，但刚从蛹中羽化出来时不能吸食血液。在第一次羽化后发生的成熟过程，即吸血和生殖营养期适应，包括一系列分子和生理变化，使雌蚊为第一次生殖周期做好准备。然而，蚊子吸血和生殖营养期适应的分子基础仍然不清楚。在这里，我们研究了在第一次吸血前的前四天，成蚊的头部和身体的分子和生化变化。我们对头和身体进行了 RNA-Seq 分析，比较了雌雄表达时间进程。在身体和头部中，分别有 811 个和 203 个基因差异表达，两个身体部位都表现出早期、中期和晚期雌性特异性表达谱。头部中肌肉发育和氧化磷酸化途径相关基因的雌性特异性上调是一个显著特征。头部线粒体耗氧量的功能评估显示，随着时间的推移，由于诱导的线粒体生物发生和含量增加，呼吸能力和与 ATP 相关的呼吸逐渐增加。这一模式强烈表明，增强头部的氧化磷酸化是吸血习惯的必要步骤。一些唾液腺基因、蛋白酶以及参与 DNA 复制和修复、核糖体生物发生和保幼激素信号转导的基因在雌性身体中特异性上调，这可能反映了生殖营养期适应。对蚊子吸血和生殖营养期适应的分子和生化机制的全面描述揭示了潜在的新的蚊子控制靶点。
