{"title":"Rnai-based functional analysis of bursicon genes related to cuticle pigmentation in a ladybird beetle","authors":"","doi":"10.1016/j.jinsphys.2024.104696","DOIUrl":null,"url":null,"abstract":"<div><p>In arthropods, the binding of a bursicon (encoded by <em>burs</em> and <em>pburs</em>) heterodimer or homodimer to a leucine-rich repeat-containing G protein coupled receptor LGR2 (encoded by <em>rk</em>) can activate many physiological processes, especially cuticle pigmentation during insect ecdysis. In the current paper, we intended to ascertain whether bursicon signaling mediates body coloration in the 28-spotted larger potato ladybird, <em>Henosepilachna vigintioctomaculata</em>, and if so, by which way bursicon signal governs the pigmentation. The high expression of <em>Hvburs</em>, <em>Hvpburs</em> and <em>Hvrk</em> occurred in the young larvae, pupae and adults, especially in the head and ventral nerve cord. RNA interference (RNAi) aided knockdown of <em>Hvburs</em>, <em>Hvpburs</em> or <em>Hvrk</em> in the prepupae caused similar phenotypic defects. The pigmentation of the resultant adults was affected, with significantly reduced dark areas on the sternums. Moreover, the accumulated mRNA levels of two sclerotin biosynthesis genes, aspartate 1-decarboxylase gene <em>Hvadc</em> and N-β-alanyldopamine synthase gene <em>Hvebony</em>, were significantly increased in the <em>Hvburs</em>, <em>Hvpburs</em> or <em>Hvrk</em> RNAi beetles. Furthermore, depletion of either <em>Hvadc</em> or <em>Hvebony</em> could completely rescue the impaired coloration on the sternums of <em>Hvpburs</em> RNAi adult. Our results supported that bursicon heterodimer-mediated signal regulate cuticle pigmentation. The bursicon signaling may tune the ratio of melanins (dark/black, brown) to sclerotins (light yellow, colorless) exerting its regulative role in the pigmentation of <em>H. vigintioctomaculata</em> sternums.</p></div>","PeriodicalId":16189,"journal":{"name":"Journal of insect physiology","volume":null,"pages":null},"PeriodicalIF":2.3000,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of insect physiology","FirstCategoryId":"97","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0022191024000842","RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENTOMOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
In arthropods, the binding of a bursicon (encoded by burs and pburs) heterodimer or homodimer to a leucine-rich repeat-containing G protein coupled receptor LGR2 (encoded by rk) can activate many physiological processes, especially cuticle pigmentation during insect ecdysis. In the current paper, we intended to ascertain whether bursicon signaling mediates body coloration in the 28-spotted larger potato ladybird, Henosepilachna vigintioctomaculata, and if so, by which way bursicon signal governs the pigmentation. The high expression of Hvburs, Hvpburs and Hvrk occurred in the young larvae, pupae and adults, especially in the head and ventral nerve cord. RNA interference (RNAi) aided knockdown of Hvburs, Hvpburs or Hvrk in the prepupae caused similar phenotypic defects. The pigmentation of the resultant adults was affected, with significantly reduced dark areas on the sternums. Moreover, the accumulated mRNA levels of two sclerotin biosynthesis genes, aspartate 1-decarboxylase gene Hvadc and N-β-alanyldopamine synthase gene Hvebony, were significantly increased in the Hvburs, Hvpburs or Hvrk RNAi beetles. Furthermore, depletion of either Hvadc or Hvebony could completely rescue the impaired coloration on the sternums of Hvpburs RNAi adult. Our results supported that bursicon heterodimer-mediated signal regulate cuticle pigmentation. The bursicon signaling may tune the ratio of melanins (dark/black, brown) to sclerotins (light yellow, colorless) exerting its regulative role in the pigmentation of H. vigintioctomaculata sternums.
期刊介绍:
All aspects of insect physiology are published in this journal which will also accept papers on the physiology of other arthropods, if the referees consider the work to be of general interest. The coverage includes endocrinology (in relation to moulting, reproduction and metabolism), pheromones, neurobiology (cellular, integrative and developmental), physiological pharmacology, nutrition (food selection, digestion and absorption), homeostasis, excretion, reproduction and behaviour. Papers covering functional genomics and molecular approaches to physiological problems will also be included. Communications on structure and applied entomology can be published if the subject matter has an explicit bearing on the physiology of arthropods. Review articles and novel method papers are also welcomed.