RRC ID 11128
Author Belgacem YH, Martin JR.
Title Hmgcr in the corpus allatum controls sexual dimorphism of locomotor activity and body size via the insulin pathway in Drosophila.
Journal PLoS ONE
Abstract The insulin signaling pathway has been implicated in several physiological and developmental processes. In mammals, it controls expression of 3-Hydroxy-3-Methylglutaryl CoA Reductase (HMGCR), a key enzyme in cholesterol biosynthesis. In insects, which can not synthesize cholesterol de novo, the HMGCR is implicated in the biosynthesis of juvenile hormone (JH). However, the link between the insulin pathway and JH has not been established. In Drosophila, mutations in the insulin receptor (InR) decrease the rate of JH synthesis. It is also known that both the insulin pathway and JH play a role in the control of sexual dimorphism in locomotor activity. In studies here, to demonstrate that the insulin pathway and HMGCR are functionally linked in Drosophila, we first show that hmgcr mutation also disrupts the sexual dimorphism. Similarly to the InR, HMGCR is expressed in the corpus allatum (ca), which is the gland where JH biosynthesis occurs. Two p[hmgcr-GAL4] lines were therefore generated where RNAi was targeted specifically against the HMGCR or the InR in the ca. We found that RNAi-HMGCR blocked HMGCR expression, while the RNAi-InR blocked both InR and HMGCR expression. Each RNAi caused disruption of sexual dimorphism and produced dwarf flies at specific rearing temperatures. These results provide evidence: (i) that HMGCR expression is controlled by the InR and (ii) that InR and HMGCR specifically in the ca, are involved in the control of body size and sexual dimorphism of locomotor activity.
Volume 2(1)
Pages e187
Published 2007-1-31
DOI 10.1371/journal.pone.0000187
PMID 17264888
PMC PMC1779623
MeSH Animals Animals, Genetically Modified Body Size* Corpora Allata / enzymology Drosophila Proteins / genetics Drosophila Proteins / metabolism Drosophila melanogaster* / anatomy & histology Drosophila melanogaster* / physiology Fat Body / enzymology Female Hydroxymethylglutaryl CoA Reductases / genetics Hydroxymethylglutaryl CoA Reductases / metabolism* Insulin / metabolism* Male Motor Activity / physiology* Mutation Phenotype RNA Interference Receptor, Insulin / genetics Receptor, Insulin / metabolism Sex Characteristics* Signal Transduction / physiology*
IF 2.766
Times Cited 52
Drosophila 10367R-1 10367R-3 18402R-1 18402R-2