Molecular Characterization and Functional Analysis of Armigeres subalbatus prophenoloxidase V

• Main Authors: Jun-Wei Chen, 陳俊瑋
• Other Authors: Cheng-Chen Chen
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/83232152246664515303

碩士 === 國立陽明大學 === 熱帶醫學研究所 === 96 === We investigated the functional role of a phenol oxidizing enzyme, designated Armigeres subalbatus prophenoloxidase V (As-pro-POV) in the mosquito Ar. subalbatus. RT-PCR analyses revealed that As-pro-POV is constitutively expressed throughout larval、pupal and adult stages of Ar. subalbatus. The level of As-pro-POV mRNA increased after blood feeding and decreased to normal level after oviposition. We used double-stranded RNA(dsRNA) to knockdown As-pro-POV and observed the phenotypic effects on egg chorion melanization. As compared to inoculated controls, As-pro-POV transcripts was dramatically reduced in Ar. subalbatus after gene knockdown and about 30% mosquito eggs laid by As-pro-POV-knockdowned mosquitoes were unmelanized. We also used dsRNA to knockdown two other melanogic enzymes, dopachrome conversion enzyme (DCE) and dopa decarboyxlase (DDC) in blood-fed Ar. subalbatus and demonstrated that egg melanization rates were significantly reduced in DCE-knockdowned mosquitoes, whilst the egg melanization rates were not significantly affected in DDC-knockdowned mosquitoes. These results indicate that both As-pro-POV and DCE play crucial roles in egg chorion melanization.