The Expression of the Transcription Factor Broad and RNA-Binding Factors in the Midgut of the Mosquito Aedes Aegypti During Metamorphosis
type: CreativeWork
description: Transcription factors, microRNAs and RNA binding factors frequently interact to coordinate gene expression during development. The transcription factor BROAD (BR) is a global regulator of insect gene transcription and governs the timing of the commitment to pupate. I determined BR expression in the Ae. aegypti midgut by qPCR, and correlated its expression with that of nine miRNAs and three RNA-binding factors. During midgut metamorphosis the expression of these factors was dynamic and reproducible. To better understand the changes in expression patterns, I evaluated the effects of hormone analogs on expression. Using this approach I uncovered concurrent up-regulation of BR, miR-34 and miR-14 in the pupal midgut when treated with methoprene, and found that RH2485 accelerated expression of BR, BRAT, and microRNAs let-7, and miR-125. Treatment with each hormone analog resulted in a change in BR expression. Finally, I evaluated the effect of nutrients on expression levels. Surprisingly, though most transcripts were down-regulated during starvation, the expression of BR did not decrease, while microRNAs miR-34 and miR-14 were elevated. This may identify a novel role for miR-34 during starvation in an invertebrate, and raises the possibility that miR-34 and miR-14 are part of a starvation-induced stress response in the mosquito midgut. In summary, this expression analysis suggests that microRNA regulation plays an important role during midgut metamorphosis, and reveals a new layer of regulatory complexity in the control of development in Ae. aegypti.
abstract: Transcription factors, microRNAs and RNA binding factors frequently interact to coordinate gene expression during development. The transcription factor BROAD (BR) is a global regulator of insect gene transcription and governs the timing of the commitment to pupate. I determined BR expression in the Ae. aegypti midgut by qPCR, and correlated its expression with that of nine miRNAs and three RNA-binding factors. During midgut metamorphosis the expression of these factors was dynamic and reproducible. To better understand the changes in expression patterns, I evaluated the effects of hormone analogs on expression. Using this approach I uncovered concurrent up-regulation of BR, miR-34 and miR-14 in the pupal midgut when treated with methoprene, and found that RH2485 accelerated expression of BR, BRAT, and microRNAs let-7, and miR-125. Treatment with each hormone analog resulted in a change in BR expression. Finally, I evaluated the effect of nutrients on expression levels. Surprisingly, though most transcripts were down-regulated during starvation, the expression of BR did not decrease, while microRNAs miR-34 and miR-14 were elevated. This may identify a novel role for miR-34 during starvation in an invertebrate, and raises the possibility that miR-34 and miR-14 are part of a starvation-induced stress response in the mosquito midgut. In summary, this expression analysis suggests that microRNA regulation plays an important role during midgut metamorphosis, and reveals a new layer of regulatory complexity in the control of development in Ae. aegypti.
author: Ray, Kathryn
keywords: Biology
date published: 2013-01-01T08:00:00Z
date modified: 2026-07-24T01:58:49Z
provider: City University of New York - Graduate Center
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: The Graduate School and University Center of The City University of New York