The Expression of the Transcription Factor Broad and RNA-Binding Factors in the Midgut of the Mosquito Aedes Aegypti During Metamorphosis

<p>Transcription factors, microRNAs and RNA binding factors frequently interact to coordinate gene expression during development. The transcription factor <em>BROAD (BR)</em> is a global regulator of insect gene transcription and governs the timing of the commitment to pupate. I determined <em>BR</em> expression in the <em>Ae. aegypti</em> 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.</p> <p>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 <em>BR, miR-34</em> and <em>miR-14</em> in the pupal midgut when treated with methoprene, and found that RH2485 accelerated expression of <em>BR, BRAT,</em> and microRNAs <em>let-7</em>, and <em>miR-125</em>. Treatment with each hormone analog resulted in a change in <em>BR</em> expression.</p> <p>Finally, I evaluated the effect of nutrients on expression levels. Surprisingly, though most transcripts were down-regulated during starvation, the expression of <em>BR</em> did not decrease, while microRNAs<em> miR-34</em> and <em>miR-14</em> were elevated. This may identify a novel role for <em>miR-34</em> during starvation in an invertebrate, and raises the possibility that <em>miR-34</em> and <em>miR-14</em> are part of a starvation-induced stress response in the mosquito midgut.</p> <p>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 <em>Ae. aegypti</em>.</p>

Name thesis:degree_name

Doctor of Philosophy

Level thesis:degree_level

Doctoral

Discipline thesis:degree_discipline

Biology

Grantor

The Graduate School and University Center of The City University of New York

Year dc:date.available

2013

Author dc:creator

• Ray, Kathryn

Advisor dc:contributor.advisor

• James T. Nishiura

Committee members dc:contributor.committeemember

• Peter N. Lipke
• Barbara Studamire
• Diana P. Bratu
• Edward B. Dubrovsky

• Biology

Repository record dc:identifier

https://academicworks.cuny.edu/gc_etds/1959

OAI identifier oai:identifier

oai:academicworks.cuny.edu:gc_etds-2997