Sex-specific expression profiles of ecdysteroid biosynthesis and ecdysone response genes in extreme sexual dimorphism of the mealybug Planococcus kraunhiae (Kuwana)
Open Access
- 13 April 2020
- journal article
- research article
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 15 (4), e0231451
- https://doi.org/10.1371/journal.pone.0231451
Abstract
Insect molting hormone (ecdysteroids) and juvenile hormone regulate molting and metamorphic events in a variety of insect species. Mealybugs undergo sexually dimorphic metamorphosis: males develop into winged adults through non-feeding, pupa-like stages called prepupa and pupa, while females emerge as neotenic wingless adults. We previously demonstrated, in the Japanese mealybug Planococcus kraunhiae (Kuwana), that the juvenile hormone titer is higher in males than in females at the end of the juvenile stage, which suggests that juvenile hormone may regulate male-specific adult morphogenesis. Here, we examined the involvement of ecdysteroids in sexually dimorphic metamorphosis. To estimate ecdysteroid titers, quantitative RT-PCR analyses of four Halloween genes encoding for cytochrome P450 monooxygenases in ecdysteroid biosynthesis, i.e., spook, disembodied, shadow and shade, were performed. Overall, their expression levels peaked before each nymphal molt. Transcript levels of spook, disembodied and shadow, genes that catalyze the steps in ecdysteroid biosynthesis in the prothoracic gland, were higher in males from the middle of the second nymphal instar to adult emergence. In contrast, the expression of shade, which was reported to be involved in the conversion of ecdysone into 20-hydroxyecdysone in peripheral tissues, was similar between males and females. These results suggest that ecdysteroid biosynthesis in the prothoracic gland is more active in males than in females, although the final conversion into 20-hydroxyecdysone occurs at similar levels in both sexes. Moreover, expression profiles of ecdysone response genes, ecdysone receptor and ecdysone-induced protein 75B, were also analyzed. Based on these expression profiles, we propose that the changes in ecdysteroid titer differ between males and females, and that high ecdysteroid titer is essential for directing male adult development.Funding Information
- Japan Society for the Promotion of Science (15K07791 and 19H02969)
This publication has 58 references indexed in Scilit:
- RNAi-mediated knockdown of Shade negatively affects ecdysone-20-hydroxylation in the desert locust, Schistocerca gregariaJournal of Insect Physiology, 2012
- MrBayes 3.2: Efficient Bayesian Phylogenetic Inference and Model Choice Across a Large Model SpaceSystematic Biology, 2012
- Nuclear Receptor DHR4 Controls the Timing of Steroid Hormone Pulses During Drosophila DevelopmentPLoS Biology, 2011
- The Conserved Rieske Oxygenase DAF-36/Neverland Is a Novel Cholesterol-metabolizing EnzymeOnline Journal of Public Health Informatics, 2011
- Transcription factor broad suppresses precocious development of adult structures during larval–pupal metamorphosis in the red flour beetle, Tribolium castaneumMechanisms of Development, 2008
- The nuclear hormone receptor BgE75 links molting and developmental progression in the direct-developing insect Blattella germanicaDevelopmental Biology, 2008
- Spook and Spookier code for stage-specific components of the ecdysone biosynthetic pathway in DipteraDevelopmental Biology, 2006
- The pupal specifier broad directs progressive morphogenesis in a direct-developing insectProceedings of the National Academy of Sciences of the United States of America, 2006
- Cytochrome P450 CYP307A1/Spook: A regulator for ecdysone synthesis in insectsBiochemical and Biophysical Research Communications, 2005
- MAFFT version 5: improvement in accuracy of multiple sequence alignmentNucleic Acids Research, 2005