Biochemistry of Chorion Hardening in Mosquitoes

描述：洪水中的蚊子，如埃及伊蚊，在 底物在水的边缘，卵只有在被淹后才会孵化 在充足的降雨之后。因此，抵抗干燥的能力和 其他不利的环境条件对这些动物的生存至关重要 鸡蛋。产卵后，绒毛膜在潮湿的环境中3-4小时内变硬。 环境，硬化的绒毛膜为发展中的 绒毛膜内的胚胎。PI已经证明了两个相互关联的 酚氧化酶/多巴脱羧酶催化的绒毛膜生化事件 黑化和过氧化物酶介导的绒毛膜蛋白交联参与其中。 在埃及伊蚊的整体绒毛硬化中。结果表明， 绒毛膜过氧化物酶催化的绒毛膜蛋白交联是至关重要的一步 过氧化物酶与其他已描述的过氧化物酶有显著的不同 它的进化方式可能反映了它在绒毛膜中的生物学作用 形成和硬化。这笔赠款的目标是实现充分的 对绒毛膜过氧化物酶和酚氧化酶的认识 绒毛膜的生物合成和硬化。具体目标包括1)隔离 绒毛膜过氧化物酶基因与时空转录的研究 2)生产用于酶特性和抗体的重组蛋白 3)绒毛膜过氧化物酶的生化特性；4) 绒毛膜酚氧化酶的生化和分子特性。 蚊媒病原体继续对人类健康产生重大影响 在全世界，抗药性寄生虫的发展和 抗药性蚊媒迫切要求新的蚊子或 制定寄生虫控制策略。中断所需的 正常发育所必需的生理生化过程 蚊子是控制蚊媒疾病的一种方法。更好的 蚊子绒毛形成的生理和生化知识 对于彻底理解这一物种的生殖过程至关重要 重要的一组病媒。卵的长期存活率 处于不利环境条件下的时间，如洪水所需 蚊子在很大程度上依赖于绒毛膜的生化过程 生物合成和硬化。预计对这一问题的解释 鸡蛋绒毛膜发育所需的生化途径及其调控 可能会为控制蚊子提供新的方法 扰乱所需的生殖过程。

DESCRIPTION: Floodwater mosquitoes, such as Aedes aegypti, oviposit on substrates at the edge of water, and the eggs hatch only after being flooded following adequate rainfall. Therefore, the ability to resist desiccation and other adverse environmental conditions is critical for the survival of these eggs. After oviposition, the chorion hardens in 3-4 hours in a moist environment, and a hardened chorion provides protection for the developing embryo within the chorion. The PI has demonstrated that two interrelated biochemical events, Phenoloxidase/dopa decarboxylase- catalyzed chorion melanization and peroxidase-mediated chorion protein crosslinking are involved in the overall chorion hardening in A. aegypti. Results indicate that the chorion peroxidase-catelyzed chorion protein crosslinking is a vital step and that the peroxidase is significantly different from other described peroxidases and has evolved in a manner that likely reflects its biological role in chorion formation and hardening. The objectives of this grant are to achieve a full understanding of the chorion peroxidase and phenoloxidase in relation to chorion biosynthesis and hardening. Specific aims include 1) isolation of the chorion peroxidase cDNA and assessment of temporal and spatial transcription, 2) production of recombinant protein for enzyme characterization and antibody production, 3) biochemical characterization of chorion peroxidase, and 4) the biochemical and molecular characterization of chorion phenoloxidase. Mosquito-borne pathogens continue to have a major impact on human health throughout the world, and the development of drug resistant parasites and insecticide resistant mosquito vectors urgently demands that new mosquito or parasite control strategies be developed. Disruption of the required physio-biochemical processes that are necessary for the normal development of mosquitoes is one approach for the control of mosquito-borne disease. A better knowledge of the physiology and biochemistry of chorion formation in mosquitoes is critical to a thorough understanding of reproductive processes in this important group of disease vectors. Survival of eggs for extended periods of time in adverse-environmental conditions, as is required for floodwater mosquitoes, is critically dependent on the biochemical process of chorion biosynthesis and hardening. It is anticipated that an elucidation of the biochemical pathways and their regulation required for egg chorion development might provide new approaches for the control of mosquitoes through the disruption of required reproductive processes.