Posttrapscriptional control of the competence factor beta FTZ-F1 by juvenile hormone in the mosquito Aedes aegypti
Autor(es): Zhu, JS; Chen, L; Raikhel, AS
Resumo: In anautogenous mosquitoes, vitellogenesis, which includes production of yolk protein precursors, requires blood feeding. Consequently, mosquitoes transmit many diseases. Understanding the molecular mechanisms of vitellogenesis regulation will contribute significantly to vector control strategies. Newly emerged Aedes aegypti females require 3 days before becoming competent to activate vitellogenesis in response to a blood-meal-initiated, elevated titer of 20-hydroxyecdysone (20E). An orphan nuclear receptor gene betaFTZ-F1 is transcribed in the fat body of newly emerged mosquito females; however, the betaFTZ-F1 protein is only found 3 days later. Dramatically increased titer of the juvenile hormone III (JH III) is essential for the acquisition of 20E competence. In vitro fat body culture experiments have shown that betaFTZ-F1 protein appears after exposure to JH III. Injection of double-stranded RNA complementary to betaFTZ-F1 into newly emerged females attenuated expression of the early genes EcR-B, E74B, and E75A and the target YPP gene Vg, in response to a blood meal. Thus, betaFTZ-F1 is indeed the factor defining the acquisition of competence to 20E in the mosquito fat body. Moreover, this is achieved through JH Ill-mediated posttranscriptional control of betaFTZ-F1.
Palavras-Chave: Ecdysteroid receptor; Fat body; Nuclear receptor; Drosophila metamorphosis; RNA interference; Differential expression; Vitellogenin synthesis; Molecular mechanism; Stage specificity; Gene expression
Imprenta: Proceedings of The National Academy of Sciences of The United States of America, v. 100, n. 23, p. 13338-13343, 2003
Identificador do objeto digital: 10.1073/pnas.2234416100
Descritores: Aedes aegypti - Cell ; Aedes aegypti - Protein synthesis ; Aedes aegypti - Proteins ; Aedes aegypti - RNA
Data de publicação: 2003
