title: Distinct roles of isoforms of the heme-liganded nuclear receptor E75, an insect ortholog of the vertebrate Rev-erb, in mosquito reproduction.
abstract: Mosquitoes are adapted to using vertebrate blood as a nutrient source to promote egg development and as a consequence serve as disease vectors. Blood-meal activated reproductive events in female mosquitoes are hormonally and nutritionally controlled with an insect steroid hormone 20-hydroxyecdysone (20E) playing a central role. The nuclear receptor E75 is an essential factor in the 20E genetic hierarchy, however functions of its three isoforms - E75A, E75B, and E75C - in mosquito reproduction are unclear. By means of specific RNA interference depletion of E75 isoforms, we identified their distinct roles in regulating the level and timing of expression of key genes involved in vitellogenesis in the fat body (an insect analog of vertebrate liver and adipose tissue) of the mosquito Aedes aegypti. Heme is required in a high level of expression of 20E-controlled genes in the fat body, and this heme action depends on E75. Thus, in mosquitoes, heme is an important signaling molecule, serving as a sensor of the availability of a protein meal for egg development. Disruption of this signaling pathway could be explored in the design of mosquito control approaches.
authors: Department of Entomology and The Institute for Integrative Genome Biology, Riverside, CA 92521, USA.
authors: Josefa
authors: J
authors: Cruz
authors: Daniel
authors: D
authors: Mane-Padros
authors: Zhen
authors: Z
authors: Zou
authors: Alexander S
authors: AS
authors: Raikhel
mesh_terms: D000330:Aedes / Q000187:drug effects / Q000502:physiology*; D000595:Amino Acid Sequence; D000818:Animals; D002478:Cells, Cultured; D004268:DNA-Binding Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D004441:Ecdysterone / Q000235:genetics / Q000378:metabolism; D005216:Fat Body / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation; D006418:Heme / Q000378:metabolism / Q000494:pharmacology; D019476:Insect Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D020033:Protein Isoforms / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D011987:Receptors, Steroid / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D012098:Reproduction / Q000187:drug effects; D015398:Signal Transduction; D014818:Vitellogenesis / Q000187:drug effects / Q000502:physiology
chemical_list: D004268:DNA-Binding Proteins; C087173:E75 protein, insect; D019476:Insect Proteins; D020033:Protein Isoforms; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D011987:Receptors, Steroid; D006418:Heme; D004441:Ecdysterone