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Chen J, Guan Z, Ma Y, Shi Q, Chen T, Waris MI, Lyu L, Lu Y, Qi G. Juvenile hormone induces reproduction via miR-1175-3p in the red imported fire ant, Solenopsis invicta. INSECT SCIENCE 2024; 31:371-386. [PMID: 37933419 DOI: 10.1111/1744-7917.13291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 09/26/2023] [Accepted: 10/10/2023] [Indexed: 11/08/2023]
Abstract
Juvenile hormone (JH) acts in the regulation of caste differentiation between queens and workers (i.e., with or without reproductive capacity) during vitellin synthesis and oogenesis in social insects. However, the regulatory mechanisms have not yet been elucidated. Here, we identified a highly expressed microRNA (miRNA), miR-1175-3p, in the red imported fire ant, Solenopsis invicta. We found that miR-1175-3p is prominently present in the fat bodies and ovaries of workers. Furthermore, miR-1175-3p interacts with its target gene, broad-complex core (Br-C), in the fat bodies. By utilizing miR-1175-3p agomir, we successfully suppressed the expression of the Br-C protein in queens, resulting in reduced vitellogenin expression, fewer eggs, and poorly developed ovaries. Conversely, decreasing miR-1175-3p levels led to the increased expression of Br-C and vitellogenin in workers, triggering the "re-development" of the ovaries. Moreover, when queens were fed with JH, the expression of miR-1175-3p decreased, whereas the expression of vitellogenin-2 and vitellogenin-3 increased. Notably, the suppression of fertility in queens caused by treatment with agomir miR-1175-3p was completely rescued by the increased vitellogenin expression induced by being fed with JH. These results suggest the critical role of miR-1175-3p in JH-regulated reproduction, shedding light on the molecular mechanism underlying miRNA-mediated fecundity in social insects and providing a novel strategy for managing S. invicta.
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Affiliation(s)
- Jie Chen
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, China
| | - Ziying Guan
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, China
| | - Yunjie Ma
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, China
- Department of Entomology, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Qingxing Shi
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, China
| | - Ting Chen
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, China
| | - Muhammad Irfan Waris
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, China
| | - Lihua Lyu
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, China
| | - Yongyue Lu
- Department of Entomology, College of Plant Protection, South China Agricultural University, Guangzhou, China
| | - Guojun Qi
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, China
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Palli SR. Juvenile hormone receptor Methoprene tolerant: Functions and applications. VITAMINS AND HORMONES 2023; 123:619-644. [PMID: 37718000 DOI: 10.1016/bs.vh.2023.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/19/2023]
Abstract
During the past 15years, after confirming Methoprene tolerant (Met) as a juvenile hormone (JH) receptor, tremendous progress has been made in understanding the function of Met in supporting JH signal transduction. Met role in JH regulation of development, including metamorphosis, reproduction, diapause, cast differentiation, behavior, im`munity, sleep and epigenetic modifications, have been elucidated. Met's Heterodimeric partners involved in performing some of these functions were discovered. The availability of JH response elements (JHRE) and JH receptor allowed the development of screening assays in cell lines and yeast. These screening assays facilitated the identification of new chemicals that function as JH agonists and antagonists. These new chemicals and others that will likely be discovered in the near future by using JH receptor and JHRE will lead to highly effective species-specific environmentally friendly insecticides for controlling pests and disease vectors.
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Affiliation(s)
- Subba Reddy Palli
- Department of Entomology, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, United States.
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Guo MP, Qian WL, He XC, Peng J, Wang P, Wang WN, Xia QY, Cheng DJ. Genome-wide identification of target genes for transcription factor BR-C in the silkworm, Bombyx mori. INSECT SCIENCE 2021; 28:1530-1540. [PMID: 33372405 DOI: 10.1111/1744-7917.12893] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 10/23/2020] [Accepted: 11/22/2020] [Indexed: 06/12/2023]
Abstract
Transcription factor Broad Complex (BR-C) is an ecdysone primary response gene in insects and participates in the regulation of insect growth and development. In this study, we performed a genome-wide identification of BR-C target genes in silkworm (Bombyx mori) using chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq). As a result, a total of 1006 BR-C ChIP peaks were identified, and 15% of peaks were located in the promoter regions of 133 protein-coding genes. Functional annotation revealed that these ChIP peak-associated genes, as potential BR-C targets, were enriched in pathways related to biosynthetic process, metabolic process, and development. Transcriptome analysis and quantitative real-time polymerase chain reaction (PCR) examination revealed that developmental changes in expression patterns of a portion of potential BR-C targets, including HR96 and GC-α1, were similar to those of BR-C. ChIP-PCR examination confirmed that BR-C could directly bind to the promoters of potential targets. Further, dual luciferase assays demonstrated that HR96 promoter activity was significantly upregulated following BR-C overexpression, and this upregulation was abolished when the binding motif in the promoter was truncated. This study will be helpful for deciphering the regulatory roles of BR-C during insect growth and development.
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Affiliation(s)
- Meng-Pei Guo
- State Key Laboratory of Silkworm Genome Biology, Biological Science Research Center, Southwest University, Chongqing, 400715, China
| | - Wen-Liang Qian
- State Key Laboratory of Silkworm Genome Biology, Biological Science Research Center, Southwest University, Chongqing, 400715, China
| | - Xue-Chuan He
- State Key Laboratory of Silkworm Genome Biology, Biological Science Research Center, Southwest University, Chongqing, 400715, China
| | - Jian Peng
- State Key Laboratory of Silkworm Genome Biology, Biological Science Research Center, Southwest University, Chongqing, 400715, China
| | - Peng Wang
- State Key Laboratory of Silkworm Genome Biology, Biological Science Research Center, Southwest University, Chongqing, 400715, China
| | - Wei-Na Wang
- State Key Laboratory of Silkworm Genome Biology, Biological Science Research Center, Southwest University, Chongqing, 400715, China
| | - Qing-You Xia
- State Key Laboratory of Silkworm Genome Biology, Biological Science Research Center, Southwest University, Chongqing, 400715, China
- Chongqing Key Laboratory of Sericultural Science, Southwest University, Chongqing, 400715, China
| | - Dao-Jun Cheng
- State Key Laboratory of Silkworm Genome Biology, Biological Science Research Center, Southwest University, Chongqing, 400715, China
- Chongqing Key Laboratory of Sericultural Science, Southwest University, Chongqing, 400715, China
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Santos CG, Humann FC, Hartfelder K. Juvenile hormone signaling in insect oogenesis. CURRENT OPINION IN INSECT SCIENCE 2019; 31:43-48. [PMID: 31109672 DOI: 10.1016/j.cois.2018.07.010] [Citation(s) in RCA: 108] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 07/15/2018] [Indexed: 06/09/2023]
Abstract
Juvenile hormone (JH) plays a crucial role in insect reproduction, but its molecular mode of action only became clear within the last decade. We here review recent findings revealing the intricate crosstalk between JH and ecdysone signaling with nutrient sensing pathways in Drosophila melanogaster, Aedes aegypti, Tribolium castaneum and Locusta migratoria. The finding for a critical role of ecdysis triggering hormone (ETH) in both molting and ooogenesis now also highlights the importance of an integrated view of development and reproduction. Furthermore, insights from non-model insects, especially so social Hymenoptera and termites, where JH function gradually becomes decoupled from reproduction and plays a role in division of labor, emphasize the need to consider life cycle and life history strategies when studying insect reproductive physiology.
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Affiliation(s)
- Carolina Gonçalves Santos
- Departamento de Biologia Celular e Molecular e Bioagentes Patogênicos, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil.
| | | | - Klaus Hartfelder
- Departamento de Biologia Celular e Molecular e Bioagentes Patogênicos, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
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5
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Transcriptomic meta-signatures identified in Anopheles gambiae populations reveal previously undetected insecticide resistance mechanisms. Nat Commun 2018; 9:5282. [PMID: 30538253 PMCID: PMC6290077 DOI: 10.1038/s41467-018-07615-x] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 11/12/2018] [Indexed: 12/01/2022] Open
Abstract
Increasing insecticide resistance in malaria-transmitting vectors represents a public health threat, but underlying mechanisms are poorly understood. Here, a data integration approach is used to analyse transcriptomic data from comparisons of insecticide resistant and susceptible Anopheles populations from disparate geographical regions across the African continent. An unbiased, integrated analysis of this data confirms previously described resistance candidates but also identifies multiple novel genes involving alternative resistance mechanisms, including sequestration, and transcription factors regulating multiple downstream effector genes, which are validated by gene silencing. The integrated datasets can be interrogated with a bespoke Shiny R script, deployed as an interactive web-based application, that maps the expression of resistance candidates and identifies co-regulated transcripts that may give clues to the function of novel resistance-associated genes. Increasing insecticide resistance of mosquitoes represents a public health threat, and underlying mechanisms are poorly understood. Here, Ingham et al. identify putative insecticide resistance genes in Anopheles gambiae populations across Africa and develop a web-based application that maps their expression.
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Schleich S, Strassburger K, Janiesch PC, Koledachkina T, Miller KK, Haneke K, Cheng YS, Kuechler K, Stoecklin G, Duncan KE, Teleman AA. DENR-MCT-1 promotes translation re-initiation downstream of uORFs to control tissue growth. Nature 2014; 512:208-212. [PMID: 25043021 PMCID: PMC4134322 DOI: 10.1038/nature13401] [Citation(s) in RCA: 122] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 04/23/2014] [Indexed: 01/01/2023]
Abstract
During cap-dependent eukaryotic translation initiation, ribosomes scan messenger RNA from the 5' end to the first AUG start codon with favourable sequence context. For many mRNAs this AUG belongs to a short upstream open reading frame (uORF), and translation of the main downstream ORF requires re-initiation, an incompletely understood process. Re-initiation is thought to involve the same factors as standard initiation. It is unknown whether any factors specifically affect translation re-initiation without affecting standard cap-dependent translation. Here we uncover the non-canonical initiation factors density regulated protein (DENR) and multiple copies in T-cell lymphoma-1 (MCT-1; also called MCTS1 in humans) as the first selective regulators of eukaryotic re-initiation. mRNAs containing upstream ORFs with strong Kozak sequences selectively require DENR-MCT-1 for their proper translation, yielding a novel class of mRNAs that can be co-regulated and that is enriched for regulatory proteins such as oncogenic kinases. Collectively, our data reveal that cells have a previously unappreciated translational control system with a key role in supporting proliferation and tissue growth.
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Affiliation(s)
- Sibylle Schleich
- German Cancer Research Center (DKFZ), Heidelberg, Germany
- Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf (UKE), Falkenried 94, 20251 Hamburg, Germany
| | | | - Philipp Christoph Janiesch
- Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf (UKE), Falkenried 94, 20251 Hamburg, Germany
| | - Tatyana Koledachkina
- Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf (UKE), Falkenried 94, 20251 Hamburg, Germany
| | - Katharine K Miller
- Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf (UKE), Falkenried 94, 20251 Hamburg, Germany
| | - Katharina Haneke
- German Cancer Research Center (DKFZ), Heidelberg, Germany
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany
| | | | - Katrin Kuechler
- Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf (UKE), Falkenried 94, 20251 Hamburg, Germany
| | - Georg Stoecklin
- German Cancer Research Center (DKFZ), Heidelberg, Germany
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany
| | - Kent E Duncan
- Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf (UKE), Falkenried 94, 20251 Hamburg, Germany
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Baumann AA, Benoit JB, Michalkova V, Mireji P, Attardo GM, Moulton JK, Wilson TG, Aksoy S. Juvenile hormone and insulin suppress lipolysis between periods of lactation during tsetse fly pregnancy. Mol Cell Endocrinol 2013; 372:30-41. [PMID: 23499946 PMCID: PMC4222070 DOI: 10.1016/j.mce.2013.02.019] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Revised: 01/30/2013] [Accepted: 02/26/2013] [Indexed: 11/30/2022]
Abstract
Tsetse flies are viviparous insects that nurture a single intrauterine progeny per gonotrophic cycle. The developing larva is nourished by the lipid-rich, milk-like secretions from a modified female accessory gland (milk gland). An essential feature of the lactation process involves lipid mobilization for incorporation into the milk. In this study, we examined roles for juvenile hormone (JH) and insulin/IGF-like (IIS) signaling pathways during tsetse pregnancy. In particular, we examined the roles for these pathways in regulating lipid homeostasis during transitions between non-lactating (dry) and lactating periods. The dry period occurs over the course of oogenesis and embryogenesis, while the lactation period spans intrauterine larvigenesis. Genes involved in the JH and IIS pathways were upregulated during dry periods, correlating with lipid accumulation between bouts of lactation. RNAi suppression of Forkhead Box Sub Group O (FOXO) expression impaired lipolysis during tsetse lactation and reduced fecundity. Similar reduction of the JH receptor Methoprene tolerant (Met), but not its paralog germ cell expressed (gce), reduced lipid accumulation during dry periods, indicating functional divergence between Met and gce during tsetse reproduction. Reduced lipid levels following Met knockdown led to impaired fecundity due to inadequate fat reserves at the initiation of milk production. Both the application of the JH analog (JHA) methoprene and injection of insulin into lactating females increased stored lipids by suppressing lipolysis and reduced transcripts of lactation-specific genes, leading to elevated rates of larval abortion. To our knowledge, this study is the first to address the molecular physiology of JH and IIS in a viviparous insect, and specifically to provide a role for JH signaling through Met in the regulation of lipid metabolism during insect lactation.
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Affiliation(s)
- Aaron A. Baumann
- Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, VA
| | - Joshua B. Benoit
- Department of Epidemiology of Microbial Diseases, School of Public Health, Yale University, New Haven, CT 06520
- Author for correspondence:
| | - Veronika Michalkova
- Department of Epidemiology of Microbial Diseases, School of Public Health, Yale University, New Haven, CT 06520
- Section of Molecular and Applied Zoology, Institute of Zoology, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Paul Mireji
- Department of Biochemistry and Molecular Biology, Egerton University, Njoro, Kenya
| | - Geoffrey M. Attardo
- Department of Epidemiology of Microbial Diseases, School of Public Health, Yale University, New Haven, CT 06520
| | - John K. Moulton
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville TN
| | - Thomas G. Wilson
- Department of Evolution, Ecology, and Organismal Biology, Ohio State University, Columbus, OH
| | - Serap Aksoy
- Department of Epidemiology of Microbial Diseases, School of Public Health, Yale University, New Haven, CT 06520
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8
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Greb-Markiewicz B, Orłowski M, Dobrucki J, Ożyhar A. Sequences that direct subcellular traffic of the Drosophila methoprene-tolerant protein (MET) are located predominantly in the PAS domains. Mol Cell Endocrinol 2011; 345:16-26. [PMID: 21745535 DOI: 10.1016/j.mce.2011.06.035] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Revised: 06/02/2011] [Accepted: 06/28/2011] [Indexed: 11/25/2022]
Abstract
Methoprene-tolerant protein (MET) is a key mediator of antimetamorphic signaling in insects. MET belongs to the family of bHLH-PAS transcription factors which regulate gene expression and determine essential physiological and developmental processes. The ability of many bHLH-PAS proteins to carry out their functions is related to the patterns of intracellular trafficking, which are determined by specific sequences and indicate that a nuclear localization signal (NLS) or a nuclear export signal (NES) is present and active. Therefore, the identification of NLS and NES signals is fundamental in order to understand the intracellular signaling role of MET. Nevertheless, data on the intracellular trafficking of MET are inconsistent, and until now there hasn't been any data on potential NLS and NES sequences. To analyze the trafficking of MET we designed a number of expression vectors encoding full-length MET, as well as various derivatives, that were fused to yellow fluorescent protein (YFP). Confocal microscopy analysis of the subcellular distribution of YFP-MET indicated that while this protein was localized mainly in the nucleus, it was also observed in the cytoplasm. This suggested the presence of both an NLS and NES in MET. Our work has shown that each of the two PAS domains of MET (PAS-A and PAS-B, respectively) contain one NLS and one NES sequence. Additional NES activity was present in the C-terminal fragment. The NLS activity located in PAS-B was dependent on the presence of juvenile hormone (JH), the potential ligand for MET. In contrast to this, JH didn't seem to be required for the NLS in PAS-A to be active. However, on the basis of current knowledge about the function of PAS-A in other bHLH-PAS proteins, we suggest there might be other proteins that control the activity of the NLS and possibly the NES located in the PAS-A of MET. Thus, the intracellular trafficking of MET seems to be regulated by a rather complicated network of different factors.
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Affiliation(s)
- Beata Greb-Markiewicz
- Department of Biochemistry, Faculty of Chemistry, Wrocław University of Technology, Poland.
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9
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Liu PC, Wang JX, Song QS, Zhao XF. The participation of calponin in the cross talk between 20-hydroxyecdysone and juvenile hormone signaling pathways by phosphorylation variation. PLoS One 2011; 6:e19776. [PMID: 21625546 PMCID: PMC3098250 DOI: 10.1371/journal.pone.0019776] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Accepted: 04/05/2011] [Indexed: 01/01/2023] Open
Abstract
20-hydroxyecdysone (20E) and juvenile hormone (JH) signaling pathways interact to mediate insect development, but the mechanism of this interaction is poorly understood. Here, a calponin homologue domain (Chd) containing protein (HaCal) is reported to play a key role in the cross talk between 20E and JH signaling by varying its phosphorylation. Chd is known as an actin binding domain present in many proteins including some signaling proteins. Using an epidermal cell line (HaEpi), HaCal was found to be up-regulated by either 20E or the JH analog methoprene (JHA). 20E induced rapid phosphorylation of HaCal whereas no phosphorylation occurred with JHA. HaCal could be quickly translocated into the nuclei through 20E or JH signaling but interacted with USP1 only under the mediation of JHA. Knockdown of HaCal by RNAi blocked the 20E inducibility of USP1, PKC and HR3, and also blocked the JHA inducibility of USP1, PKC and JHi. After gene silencing of HaCal by ingestion of dsHaCal expressed by Escherichia coli, the larval development was arrested and the gene expression of USP1, PKC, HR3 and JHi were blocked. These composite data suggest that HaCal plays roles in hormonal signaling by quickly transferring into nucleus to function as a phosphorylated form in the 20E pathway and as a non-phosphorylated form interacting with USP1 in the JH pathway to facilitate 20E or JH signaling cascade, in short, by switching its phosphorylation status to regulate insect development.
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Affiliation(s)
- Peng-Cheng Liu
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Sciences, Shandong University, Jinan, China
| | - Jin-Xing Wang
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Sciences, Shandong University, Jinan, China
| | - Qi-Sheng Song
- Division of Plant Sciences, University of Missouri, Columbia, Missouri, United States of America
| | - Xiao-Fan Zhao
- The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Sciences, Shandong University, Jinan, China
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Zhang Z, Xu J, Sheng Z, Sui Y, Palli SR. Steroid receptor co-activator is required for juvenile hormone signal transduction through a bHLH-PAS transcription factor, methoprene tolerant. J Biol Chem 2010; 286:8437-8447. [PMID: 21190938 DOI: 10.1074/jbc.m110.191684] [Citation(s) in RCA: 162] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Metamorphosis in insects is regulated by juvenile hormone (JH) and ecdysteroids. The mechanism of 20-hydroxyecdysone (20E), but not of JH action, is well understood. A basic helix-loop-helix (bHLH)-Per-Arnt-Sim (PAS) family member, methoprene tolerant (Met), plays an important role in JH action. Microarray analysis and RNA interference (RNAi) were used to identify 69 genes that require Met for their hydroprene-regulated expression in the red flour beetle, Tribolium castaneum. Quantitative real time PCR analysis confirmed microarray data for 13 of the 16 hydroprene-response genes tested. The members of the bHLH-PAS family often function as heterodimers to regulate gene expression and Met is a member of this family. To determine whether other members of the bHLH-PAS family are required for the expression of JH-response genes, we employed RNAi to knockdown the expression of all 11 members of the bHLH-PAS family and studied the expression of JH-response genes in RNAi insects. These studies showed that besides Met, another member of this family, steroid receptor co-activator (SRC) is required for the expression of 15 JH-response genes tested. Moreover, studies in JH responsive Aag-2 cells revealed that Aedes aegypti homologues of both Met and SRC are required for the expression of the JH-response gene, kr-h1, and SRC is required for expression of ecdysone-response genes. These data suggest the steroid receptor co-activator plays key roles in both JH and 20E action suggesting that this may be an important molecule that mediates cross-talk between JH and 20E to prevent metamorphosis.
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Affiliation(s)
- Zhaolin Zhang
- From the Department of Entomology, College of Agriculture, University of Kentucky, Lexington, Kentucky 40546
| | - Jingjing Xu
- From the Department of Entomology, College of Agriculture, University of Kentucky, Lexington, Kentucky 40546
| | - Zhentao Sheng
- From the Department of Entomology, College of Agriculture, University of Kentucky, Lexington, Kentucky 40546
| | - Yipeng Sui
- From the Department of Entomology, College of Agriculture, University of Kentucky, Lexington, Kentucky 40546
| | - Subba R Palli
- From the Department of Entomology, College of Agriculture, University of Kentucky, Lexington, Kentucky 40546.
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11
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Guerrero-Bosagna C, Settles M, Lucker B, Skinner MK. Epigenetic transgenerational actions of vinclozolin on promoter regions of the sperm epigenome. PLoS One 2010; 5. [PMID: 20927350 PMCID: PMC2948035 DOI: 10.1371/journal.pone.0013100] [Citation(s) in RCA: 289] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2010] [Accepted: 08/31/2010] [Indexed: 12/16/2022] Open
Abstract
Previous observations have demonstrated that embryonic exposure to the endocrine disruptor vinclozolin during gonadal sex determination promotes transgenerational adult onset disease such as male infertility, kidney disease, prostate disease, immune abnormalities and tumor development. The current study investigates genome-wide promoter DNA methylation alterations in the sperm of F3 generation rats whose F0 generation mother was exposed to vinclozolin. A methylated DNA immunoprecipitation with methyl-cytosine antibody followed by a promoter tilling microarray (MeDIP-Chip) procedure was used to identify 52 different regions with statistically significant altered methylation in the sperm promoter epigenome. Mass spectrometry bisulfite analysis was used to map the CpG DNA methylation and 16 differential DNA methylation regions were confirmed, while the remainder could not be analyzed due to bisulfite technical limitations. Analysis of these validated regions identified a consensus DNA sequence (motif) that associated with 75% of the promoters. Interestingly, only 16.8% of a random set of 125 promoters contained this motif. One candidate promoter (Fam111a) was found to be due to a copy number variation (CNV) and not a methylation change, suggesting initial alterations in the germline epigenome may promote genetic abnormalities such as induced CNV in later generations. This study identifies differential DNA methylation sites in promoter regions three generations after the initial exposure and identifies common genome features present in these regions. In addition to primary epimutations, a potential indirect genetic abnormality was identified, and both are postulated to be involved in the epigenetic transgenerational inheritance observed. This study confirms that an environmental agent has the ability to induce epigenetic transgenerational changes in the sperm epigenome.
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Affiliation(s)
- Carlos Guerrero-Bosagna
- Center for Reproductive Biology, School of Biological Sciences, Washington State University, Pullman, Washington, United States of America
| | - Matthew Settles
- Center for Reproductive Biology, School of Biological Sciences, Washington State University, Pullman, Washington, United States of America
| | - Ben Lucker
- Center for Reproductive Biology, School of Biological Sciences, Washington State University, Pullman, Washington, United States of America
| | - Michael K. Skinner
- Center for Reproductive Biology, School of Biological Sciences, Washington State University, Pullman, Washington, United States of America
- * E-mail:
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12
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Fraichard S, Bougé AL, Kendall T, Chauvel I, Bouhin H, Bunch TA. Tenectin is a novel alphaPS2betaPS integrin ligand required for wing morphogenesis and male genital looping in Drosophila. Dev Biol 2010; 340:504-17. [PMID: 20152825 DOI: 10.1016/j.ydbio.2010.02.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Revised: 01/29/2010] [Accepted: 02/02/2010] [Indexed: 10/19/2022]
Abstract
Morphogenesis of the adult structures of holometabolous insects is regulated by ecdysteroids and juvenile hormones and involves cell-cell interactions mediated in part by the cell surface integrin receptors and their extracellular matrix (ECM) ligands. These adhesion molecules and their regulation by hormones are not well characterized. We describe the gene structure of a newly described ECM molecule, tenectin, and demonstrate that it is a hormonally regulated ECM protein required for proper morphogenesis of the adult wing and male genitalia. Tenectin's function as a new ligand of the PS2 integrins is demonstrated by both genetic interactions in the fly and by cell spreading and cell adhesion assays in cultured cells. Its interaction with the PS2 integrins is dependent on RGD and RGD-like motifs. Tenectin's function in looping morphogenesis in the development of the male genitalia led to experiments that demonstrate a role for PS integrins in the execution of left-right asymmetry.
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Affiliation(s)
- Stéphane Fraichard
- Centre des Sciences du Goût et de l'Alimentation, UMR-6265 CNRS, INRA, Université de Bourgogne, Agrosup Dijon, F-21000 Dijon, France
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13
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Spokony RF, Restifo LL. Broad Complex isoforms have unique distributions during central nervous system metamorphosis in Drosophila melanogaster. J Comp Neurol 2009; 517:15-36. [PMID: 19711379 DOI: 10.1002/cne.22119] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Broad Complex (BRC) is a highly conserved, ecdysone-pathway gene essential for metamorphosis in Drosophila melanogaster, and possibly all holometabolous insects. Alternative splicing among duplicated exons produces several BRC isoforms, each with one zinc-finger DNA-binding domain (Z1, Z2, Z3, or Z4), highly expressed at the onset of metamorphosis. BRC-Z1, BRC-Z2, and BRC-Z3 represent distinct genetic functions (BRC complementation groups rbp, br, and 2Bc, respectively) and are required at discrete stages spanning final-instar larva through very young pupa. We showed previously that morphogenetic movements necessary for adult CNS maturation require BRC-Z1, -Z2, and -Z3, but not at the same time: BRC-Z1 is required in the mid-prepupa, BRC-Z2 and -Z3 are required earlier, at the larval-prepupal transition. To explore how BRC isoforms controlling the same morphogenesis events do so at different times, we examined their central nervous system (CNS) expression patterns during the approximately 16 hours bracketing the hormone-regulated start of metamorphosis. Each isoform had a unique pattern, with BRC-Z3 being the most distinctive. There was some colocalization of isoform pairs, but no three-way overlap of BRC-Z1, -Z2, and -Z3. Instead, their most prominent expression was in glia (BRC-Z1), neuroblasts (BRC-Z2), or neurons (BRC-Z3). Despite sequence similarity to BRC-Z1, BRC-Z4 was expressed in a unique subset of neurons. These data suggest a switch in BRC isoform choice, from BRC-Z2 in proliferating cells to BRC-Z1, BRC-Z3, or BRC-Z4 in differentiating cells. Together with isoform-selective temporal requirements and phenotype considerations, this cell-type-selective expression suggests a model of BRC-dependent CNS morphogenesis resulting from intercellular interactions, culminating in BRC-Z1-controlled, glia-mediated CNS movements in late prepupa.
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Affiliation(s)
- Rebecca F Spokony
- Graduate Interdisciplinary Program in Insect Science, University of Arizona, Tucson, Arizona 85721-0108, USA.
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14
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Liu Y, Sheng Z, Liu H, Wen D, He Q, Wang S, Shao W, Jiang RJ, An S, Sun Y, Bendena WG, Wang J, Gilbert LI, Wilson TG, Song Q, Li S. Juvenile hormone counteracts the bHLH-PAS transcription factors MET and GCE to prevent caspase-dependent programmed cell death in Drosophila. Development 2009; 136:2015-25. [DOI: 10.1242/dev.033712] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Juvenile hormone (JH) regulates many developmental and physiological events in insects, but its molecular mechanism remains conjectural. Here we report that genetic ablation of the corpus allatum cells of the Drosophilaring gland (the JH source) resulted in JH deficiency, pupal lethality and precocious and enhanced programmed cell death (PCD) of the larval fat body. In the fat body of the JH-deficient animals, Dronc and Drice,two caspase genes that are crucial for PCD induced by the molting hormone 20-hydroxyecdysone (20E), were significantly upregulated. These results demonstrated that JH antagonizes 20E-induced PCD by restricting the mRNA levels of Dronc and Drice. The antagonizing effect of JH on 20E-induced PCD in the fat body was further confirmed in the JH-deficient animals by 20E treatment and RNA interference of the 20E receptor EcR. Moreover, MET and GCE, the bHLH-PAS transcription factors involved in JH action, were shown to induce PCD by upregulating Droncand Drice. In the Met- and gce-deficient animals, Dronc and Drice were downregulated, whereas in the Met-overexpression fat body, Dronc and Drice were significantly upregulated leading to precocious and enhanced PCD, and this upregulation could be suppressed by application of the JH agonist methoprene. For the first time, we demonstrate that JH counteracts MET and GCE to prevent caspase-dependent PCD in controlling fat body remodeling and larval-pupal metamorphosis in Drosophila.
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Affiliation(s)
- Ying Liu
- Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Zhentao Sheng
- Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Hanhan Liu
- Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Di Wen
- Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Qianyu He
- Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Sheng Wang
- Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Wei Shao
- Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Rong-Jing Jiang
- Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Shiheng An
- Division of Plant Sciences, University of Missouri, Columbia, MO 65211,USA
| | - Yaning Sun
- Division of Plant Sciences, University of Missouri, Columbia, MO 65211,USA
| | - William G. Bendena
- Department of Biology, Queen's University, Kingston, Ontario K7L 3N6,Canada
| | - Jian Wang
- Department of Entomology, University of Maryland, College Park, MD 20742,USA
| | - Lawrence I. Gilbert
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599,USA
| | - Thomas G. Wilson
- Department of Entomology, Ohio State University, Columbus, OH 43210,USA
| | - Qisheng Song
- Division of Plant Sciences, University of Missouri, Columbia, MO 65211,USA
| | - Sheng Li
- Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
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15
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Marcucci R, Romano M, Feiguin F, O'Connell MA, Baralle FE. Dissecting the splicing mechanism of the Drosophila editing enzyme; dADAR. Nucleic Acids Res 2009; 37:1663-71. [PMID: 19153139 PMCID: PMC2655694 DOI: 10.1093/nar/gkn1080] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2008] [Revised: 12/19/2008] [Accepted: 12/23/2008] [Indexed: 11/14/2022] Open
Abstract
In Drosophila melanogaster, the expression of adenosine deaminase acting on RNA is regulated by transcription and alternative splicing so that at least four different isoforms are generated that have a tissue-specific splicing pattern. Even though dAdar has been extensively studied, the complete adult expression pattern has yet to be elucidated. In the present study, we investigate mature transcripts of dAdar arising from different promoters. Two predominant isoforms of dAdar are expressed in gonads and dAdar is transcribed from both the embryonic and the adult promoters. Furthermore, full-length transcripts containing the alternatively spliced exon-1 are expressed in a tissue-specific manner. The splicing factor B52/SRp55 binds within the alternative spliced exon 3a and plays a role in this alternative splicing event.
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Affiliation(s)
- Roberto Marcucci
- International Centre for Genetic Engineering and Biotechnology, Padriciano 99, I-34012, Department of Physiology and Pathology, University of Trieste, Via A. Fleming 22, 34127, Trieste, Italy and MRC Human Genetics Unit Western General Hospital, Edinburgh EH4 2X U, UK
| | - Maurizio Romano
- International Centre for Genetic Engineering and Biotechnology, Padriciano 99, I-34012, Department of Physiology and Pathology, University of Trieste, Via A. Fleming 22, 34127, Trieste, Italy and MRC Human Genetics Unit Western General Hospital, Edinburgh EH4 2X U, UK
| | - Fabian Feiguin
- International Centre for Genetic Engineering and Biotechnology, Padriciano 99, I-34012, Department of Physiology and Pathology, University of Trieste, Via A. Fleming 22, 34127, Trieste, Italy and MRC Human Genetics Unit Western General Hospital, Edinburgh EH4 2X U, UK
| | - Mary A. O'Connell
- International Centre for Genetic Engineering and Biotechnology, Padriciano 99, I-34012, Department of Physiology and Pathology, University of Trieste, Via A. Fleming 22, 34127, Trieste, Italy and MRC Human Genetics Unit Western General Hospital, Edinburgh EH4 2X U, UK
| | - Francisco E. Baralle
- International Centre for Genetic Engineering and Biotechnology, Padriciano 99, I-34012, Department of Physiology and Pathology, University of Trieste, Via A. Fleming 22, 34127, Trieste, Italy and MRC Human Genetics Unit Western General Hospital, Edinburgh EH4 2X U, UK
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16
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Bitra K, Palli SR. Interaction of proteins involved in ecdysone and juvenile hormone signal transduction. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2009; 70:90-105. [PMID: 18980211 DOI: 10.1002/arch.20281] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Ecdysteroids and juvenile hormones (JH) regulate a variety of developmental, physiological, behavioral, and metabolic processes. Ecdysteroids function through a heterodimeric complex of two nuclear receptors, ecdysone receptor (EcR) and ultraspiracle (USP). An 85 kDa protein identified in Drosophila melanogaster methoprene-tolerant (Met) mutant binds to JH III with high affinity, and the mutant flies are resistant to juvenile hormone analog (JHA), methoprene. Reporter assays using the yeast two-hybrid system were performed in order to study the molecular interactions between EcR, USP and Met. As expected, EcR fused to the B42 activation domain and USP fused to the LexA DNA binding domain interacted with each other and supported induction of the reporter gene in the presence of stable ecdysteroid analog, RG-102240 or steroids, muristerone A and ponasterone A. The USP:USP homodimers supported expression of the reporter gene in the absence of ligand, and there was no significant increase in the reporter activity after addition of a JHA, methoprene. Similarly, Met:Met homodimers as well as Met:EcR and Met:USP heterodimers induced reporter activity in the absence of ligand and addition of ecdysteroid or JH analogs did not increase the reporter activity regulated by either homodimers or heterodimers of Met protein. Two-hybrid assays in insect cells and in vitro pull-down assays confirmed the interaction of Met with EcR and USP. These data suggest that the proteins that are involved in signal transduction of ecdysteroids (EcR and USP) and juvenile hormones (Met) interact to mediate cross-talk between these two important hormones. Arch. Insect Biochem. Physiol. 2008. (c) 2008 Wiley-Liss, Inc.
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Affiliation(s)
- Kavita Bitra
- Department of Entomology, University of Kentucky, Lexington, KY 40506, USA
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17
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Flatt T, Heyland A, Rus F, Porpiglia E, Sherlock C, Yamamoto R, Garbuzov A, Palli SR, Tatar M, Silverman N. Hormonal regulation of the humoral innate immune response in Drosophila melanogaster. ACTA ACUST UNITED AC 2008; 211:2712-24. [PMID: 18689425 DOI: 10.1242/jeb.014878] [Citation(s) in RCA: 182] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Juvenile hormone (JH) and 20-hydroxy-ecdysone (20E) are highly versatile hormones, coordinating development, growth, reproduction and aging in insects. Pulses of 20E provide key signals for initiating developmental and physiological transitions, while JH promotes or inhibits these signals in a stage-specific manner. Previous evidence suggests that JH and 20E might modulate innate immunity, but whether and how these hormones interact to regulate the immune response remains unclear. Here we show that JH and 20E have antagonistic effects on the induction of antimicrobial peptide (AMP) genes in Drosophila melanogaster. 20E pretreatment of Schneider S2 cells promoted the robust induction of AMP genes, following immune stimulation. On the other hand, JH III, and its synthetic analogs (JHa) methoprene and pyriproxyfen, strongly interfered with this 20E-dependent immune potentiation, although these hormones did not inhibit other 20E-induced cellular changes. Similarly, in vivo analyses in adult flies confirmed that JH is a hormonal immuno-suppressor. RNA silencing of either partner of the ecdysone receptor heterodimer (EcR or Usp) in S2 cells prevented the 20E-induced immune potentiation. In contrast, silencing methoprene-tolerant (Met), a candidate JH receptor, did not impair immuno-suppression by JH III and JHa, indicating that in this context MET is not a necessary JH receptor. Our results suggest that 20E and JH play major roles in the regulation of gene expression in response to immune challenge.
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Affiliation(s)
- Thomas Flatt
- Division of Biology and Medicine, Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02912, USA
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18
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Riddiford LM. Juvenile hormone action: a 2007 perspective. JOURNAL OF INSECT PHYSIOLOGY 2008; 54:895-901. [PMID: 18355835 DOI: 10.1016/j.jinsphys.2008.01.014] [Citation(s) in RCA: 138] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2007] [Revised: 01/28/2008] [Accepted: 01/31/2008] [Indexed: 05/26/2023]
Abstract
Juvenile hormone (JH) is a key hormone in regulation of the insect's life history, both in maintaining the larval state during molts and in directing reproductive maturation. This short review highlights the recent papers of the past year that lend new insight into the role of this hormone in the larva and the mechanisms whereby it achieves this role.
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Affiliation(s)
- Lynn M Riddiford
- Janelia Farm Research Campus, Howard Hughes Medical Institute, 19700 Helix Drive, Ashburn, VA 20147, USA.
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19
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Abstract
Application of a high dose of juvenile hormone (JH) III or its mimics (JHM) to Drosophila at the white puparium stage causes the formation of a pupal-like abdomen with few or no short bristles. We report here that the rosy (ry) gene encoding the enzyme xanthine dehydrogenase (XDH), which catalyzes the final two-step oxidation in purine catabolism, is required for this effect of JH on the epidermis. In ry506 (null allele) homozygotes or hemizygotes, JH III or pyriproxifen (a JHM) had little effect on abdominal bristle or cuticle formation, but disrupted the development of the central nervous system as in wild-type flies. Wild-type ry rescued the JH sensitivity of the abdominal epidermis in ry506 mutants. Inhibition of XDH activity phenocopied the ry null mutant's insensitivity to JH. Larvae fed on hypoxanthine or xanthine showed a decreased JH sensitivity. ry506 clones were sensitive to JH, indicating that ry is required non-cell autonomously for the JH effects. Normally JH applied at pupariation causes the aberrant reexpression of the transcription factor broad in the abdominal epidermis during adult development, but in the ry506 mutant most of the cells in the dorsal tergite showed no broad reexpression, indicating that ry is upstream of broad in the JH signaling pathway.
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20
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Parthasarathy R, Tan A, Palli SR. bHLH-PAS family transcription factor methoprene-tolerant plays a key role in JH action in preventing the premature development of adult structures during larval-pupal metamorphosis. Mech Dev 2008; 125:601-16. [PMID: 18450431 DOI: 10.1016/j.mod.2008.03.004] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2008] [Revised: 03/14/2008] [Accepted: 03/15/2008] [Indexed: 11/18/2022]
Abstract
The biological actions of juvenile hormones are well studied; they regulate almost all aspects of an insect's life. However, the molecular actions of these hormones are not well understood. Recent studies in the red flour beetle, Tribolium castaneum, demonstrated the utility of this insect as a model system to study JH action. These studies confirmed that the bHLH-PAS family transcription factor, methoprene-tolerant (TcMet,) plays a key role in JH action during larval stages. In this study, we investigated the role of TcMet in JH action during larval-pupal metamorphosis. The phenotypes of TcMet RNAi insects shared similarity with the phenotypes of some allatectomized lepidopteran larvae that were attempting to undergo precocious larval-pupal metamorphosis. Knocking-down TcMet during the final instar also disrupted larval-pupal ecdysis, resulting in the development of adultoid underneath the larval skin. However, the loss of TcMet did not completely block remodeling of internal tissues such as midgut. T. castaneum larvae injected with TcMet dsRNA demonstrated a resistance to a JH analog (JHA), hydroprene, irrespective of time and route of application. Knocking-down TcMet also caused down regulation of JH-response genes, JHE and Kr-h1 suggesting that TcMet might be involved in the expression of these genes. Based on the phenotype, gene expression, and JHA action studies in TcMet RNAi insects, this study concludes that Met plays a key role in JH action for preventing the premature development of adult structures during larval-pupal metamorphosis.
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Affiliation(s)
- R Parthasarathy
- Department of Entomology, College of Agriculture, University of Kentucky, S225 Ag. Science N, Lexington, KY 40546, USA
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21
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Barry J, Wang S, Wilson TG. Overexpression of Methoprene-tolerant, a Drosophila melanogaster gene that is critical for juvenile hormone action and insecticide resistance. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2008; 38:346-353. [PMID: 18252248 PMCID: PMC2262159 DOI: 10.1016/j.ibmb.2007.12.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2007] [Revised: 12/01/2007] [Accepted: 12/04/2007] [Indexed: 05/25/2023]
Abstract
The Methoprene-tolerant (Met) gene of Drosophila melanogaster is involved in both juvenile hormone (JH) action and resistance to JH insecticides, such as methoprene. Although the consequences of Met mutations on development and methoprene resistance are known, no studies have examined Met+ overexpression. Met+ was overexpressed in transgenic lines with various promoters that drive overexpression to different levels. Flies expressing either genomic or cDNA Met+ transgenes showed higher susceptibility to both the morphogenetic and toxic effects of methoprene, consistent with the hormone-binding property of MET. Both the sensitive period and lethal period were the same as seen for non-overexpressing Met+ flies. However, continual exposure of high-overexpressing Met+ larvae to borderline-toxic or higher methoprene doses advanced the sensitive period from prepupae to first instar and the lethal period from pharate adults to larvae and early pupae. When expression of transgenic UAS-Met+ was driven to high levels by either an actin-GAL4 or tubulin-GAL4 promoter, larvae showed high mortality in the absence of methoprene, indicating that high MET titer is lethal, perhaps resulting from expression in an inappropriate tissue. Adults overexpressing Met+ did not show enhanced oogenesis, ruling out MET as a limiting factor for this hormone-driven physiology.
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22
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Konopova B, Jindra M. Broad-Complex acts downstream of Met in juvenile hormone signaling to coordinate primitive holometabolan metamorphosis. Development 2008; 135:559-68. [DOI: 10.1242/dev.016097] [Citation(s) in RCA: 149] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Metamorphosis of holometabolous insects, an elaborate change of form between larval, pupal and adult stages, offers an ideal system to study the regulation of morphogenetic processes by hormonal signals. Metamorphosis involves growth and differentiation, tissue remodeling and death, all of which are orchestrated by the morphogenesis-promoting ecdysteroids and the antagonistically acting juvenile hormone (JH), whose presence precludes the metamorphic changes. How target tissues interpret this combinatorial effect of the two hormonal cues is poorly understood, mainly because JH does not prevent larval-pupal transformation in the derived Drosophila model, and because the JH receptor is unknown. We have recently used the red flour beetle Tribolium castaneum to show that JH controls entry to metamorphosis via its putative receptor Methoprene-tolerant (Met). Here, we demonstrate that Met mediates JH effects on the expression of the ecdysteroid-response gene Broad-Complex (BR-C). Using RNAi and a classical mutant, we show that Tribolium BR-C is necessary for differentiation of pupal characters. Furthermore, heterochronic combinations of retarded and accelerated phenotypes caused by impaired BR-C function suggest that besides specifying the pupal fate, BR-C operates as a temporal coordinator of hormonally regulated morphogenetic events across epidermal tissues. Similar results were also obtained when using the lacewing Chrysopa perla (Neuroptera), a member of another holometabolous group with a primitive type of metamorphosis. The tissue coordination role of BR-C may therefore be a part of the Holometabola groundplan.
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Affiliation(s)
- Barbora Konopova
- Biology Center, Czech Academy of Sciences and Department of Molecular Biology, University of South Bohemia, Branisovska 31, Ceske Budejovice 37005,Czech Republic
| | - Marek Jindra
- Biology Center, Czech Academy of Sciences and Department of Molecular Biology, University of South Bohemia, Branisovska 31, Ceske Budejovice 37005,Czech Republic
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23
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Li Y, Zhang Z, Robinson GE, Palli SR. Identification and characterization of a juvenile hormone response element and its binding proteins. J Biol Chem 2007; 282:37605-17. [PMID: 17956872 PMCID: PMC3556787 DOI: 10.1074/jbc.m704595200] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Juvenile hormones (JH) regulate a wide variety of developmental and physiological processes in insects. Comparison of microarray data on JH-induced genes in the fruit fly, Drosophila melanogaster, L57 cells and in the honey bee, Apis mellifera, identified 16 genes that are induced in both species. Analysis of promoter regions of these 16 D. melanogaster genes identified DmJHRE1 (D. melanogaster JH response element 1). In L57 cells, the reporter gene regulated by DmJHRE1 was induced by JH III. Two proteins (FKBP39 and Chd64) that bind to DmJHRE1 were identified. FKBP39 and Chd64 double-stranded RNA inhibited JH III induction of a reporter gene regulated by DmJHRE1. FKBP39 and Chd64 proteins expressed in yeast bound to DmJHRE1. Two-hybrid and pull-down assays showed that these two proteins interact with each other as well as with ecdysone receptor, ultraspiracle, and methoprene-tolerant protein. Developmental expression profiles and JH induction of mRNA for FKBP39 and Chd64 proteins and their interaction with proteins known to be involved in both JH (methoprene-tolerant protein) and ecdysteroid action (ecdysone receptor and ultraspiracle) suggest that these proteins probably play important roles in cross-talk between JH and ecdysteroids.
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Affiliation(s)
- Yiping Li
- Department of Entomology, University of Kentucky, Lexington, Kentucky 40546
| | - Zhaolin Zhang
- Department of Entomology, University of Kentucky, Lexington, Kentucky 40546
| | - Gene E. Robinson
- Department of Entomology and Neuroscience Program, University of Illinois, Urbana, Illinois 61801
| | - Subba R. Palli
- Department of Entomology, University of Kentucky, Lexington, Kentucky 40546
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Konopova B, Jindra M. Juvenile hormone resistance gene Methoprene-tolerant controls entry into metamorphosis in the beetle Tribolium castaneum. Proc Natl Acad Sci U S A 2007; 104:10488-93. [PMID: 17537916 PMCID: PMC1965540 DOI: 10.1073/pnas.0703719104] [Citation(s) in RCA: 228] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Besides being a spectacular developmental process, metamorphosis is key to insect success. Entry into metamorphosis is controlled by juvenile hormone (JH). In larvae, JH prevents pupal and adult morphogenesis, thus keeping the insect in its immature state. How JH signals to preclude metamorphosis is poorly understood, and a JH receptor remains unknown. One candidate for the JH receptor role is the Methoprene-tolerant (Met) Per-Arnt-Sim (PAS) domain protein [also called Resistance to JH, Rst (1)JH], whose loss confers tolerance to JH and its mimic methoprene in the fruit fly Drosophila melanogaster. However, Met deficiency does not affect the larval-pupal transition, possibly because this process does not require JH absence in Drosophila. By contrast, the red flour beetle Tribolium castaneum is sensitive to developmental regulation by JH, thus making an ideal system to examine the role of Met in the antimetamorphic JH action. Here we show that impaired function of the Met ortholog TcMet renders Tribolium resistant to the effects of ectopic JH and, in a striking contrast to Drosophila, causes early-stage beetle larvae to undergo precocious metamorphosis. This is evident as TcMet-deficient larvae pupate prematurely or develop specific heterochronic phenotypes such as pupal-like cuticular structures, appendages, and compound eyes. Our results demonstrate that TcMet functions in JH response and provide the critical evidence that the putative JH receptor Met mediates the antimetamorphic effect of JH.
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Affiliation(s)
- Barbora Konopova
- *Department of Molecular Biology, University of South Bohemia, and
| | - Marek Jindra
- Biology Center, Czech Academy of Sciences, 37005 Ceske Budejovice, Czech Republic
- To whom correspondence should be addressed. E-mail:
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25
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Spokony RF, Restifo LL. Anciently duplicated Broad Complex exons have distinct temporal functions during tissue morphogenesis. Dev Genes Evol 2007; 217:499-513. [PMID: 17530286 DOI: 10.1007/s00427-007-0159-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2006] [Accepted: 04/20/2007] [Indexed: 12/22/2022]
Abstract
Broad Complex (BRC) is an essential ecdysone-pathway gene required for entry into and progression through metamorphosis in Drosophila melanogaster. Mutations of three BRC complementation groups cause numerous phenotypes, including a common suite of morphogenesis defects involving central nervous system (CNS), adult salivary glands (aSG), and male genitalia. These defects are phenocopied by the juvenile hormone mimic methoprene. Four BRC isoforms are produced by alternative splicing of a protein-binding BTB/POZ-encoding exon (BTBBRC) to one of four tandemly duplicated, DNA-binding zinc-finger-encoding exons (Z1BRC, Z2BRC, Z3BRC, Z4BRC). Highly conserved orthologs of BTBBRC and all four ZBRC were found among published cDNA sequences or genome databases from Diptera, Lepidoptera, Hymenoptera, and Coleoptera, indicating that BRC arose and underwent internal exon duplication before the split of holometabolous orders. Tramtrack subfamily members, abrupt, tramtrack, fruitless, longitudinals lacking (lola), and CG31666 were characterized throughout Holometabola and used to root phylogenetic analyses of ZBRC exons, which revealed that the ZBRC clade includes Zabrupt. All four ZBRC domains, including Z4BRC, which has no known essential function, are evolving in a manner consistent with selective constraint. We used transgenic rescue to explore how different BRC isoforms contribute to shared tissue-morphogenesis functions. As predicted from earlier studies, the common CNS and aSG phenotypes were rescued by BRC-Z1 in rbp mutants, BRC-Z2 in br mutants, and BRC-Z3 in 2Bc mutants. However, the isoforms are required at two different developmental stages, with BRC-Z2 and -Z3 required earlier than BRC-Z1. The sequential action of BRC isoforms indicates subfunctionalization of duplicated ZBRC exons even when they contribute to common developmental processes.
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Affiliation(s)
- Rebecca F Spokony
- Graduate Interdisciplinary Program in Insect Science, University of Arizona, Tucson, AZ 85721-0108, USA.
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Wang S, Baumann A, Wilson TG. Drosophila melanogaster Methoprene-tolerant (Met) gene homologs from three mosquito species: Members of PAS transcriptional factor family. JOURNAL OF INSECT PHYSIOLOGY 2007; 53:246-53. [PMID: 17166512 PMCID: PMC1904834 DOI: 10.1016/j.jinsphys.2006.07.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2006] [Revised: 06/30/2006] [Accepted: 07/03/2006] [Indexed: 05/09/2023]
Abstract
The Methoprene-tolerant (Met) gene in Drosophila melanogaster has been shown to function in juvenile hormone (JH) action. Met homologs were isolated from three mosquito species, Culex pipiens, Aedes aegypti and Anopheles gambiae. Sequence similarity was found to be high in bHLH and PAS conserved domains, and the majority of the 7-9 introns in AaMet and AgMet are located in either identical or similar positions, indicating evolutionary relatedness. Sequence comparison with Met and the similar germ-cell expressed (gce) gene in D. melanogaster showed that the mosquito genes are more similar to gce than to Met. Moreover, the multiple introns in AgMet and AaMet are more similar in number with the 7 introns in Dmgce than to the single intron in DmMet; in fact, six intron positions in AaMet and AgMet are similar to those in Dmgce. Efforts to identify a second homologous gene in mosquitoes were unsuccessful, suggesting a single gene in lower Diptera, consistent with the single gene uncovered in genomic sequencing of Ae. aegypti and An. gambiae. These results suggest that a gene duplication occurred during the evolution of higher Diptera, resulting in Met and gce.
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Affiliation(s)
| | | | - Thomas G. Wilson
- *: Author for correspondence. E-mail: , Phone: 614-247-6036, Fax: 614-292-2180
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Beatty J, Fauth T, Callender JL, Spindler-Barth M, Henrich VC. Analysis of transcriptional activity mediated by Drosophila melanogaster ecdysone receptor isoforms in a heterologous cell culture system. INSECT MOLECULAR BIOLOGY 2006; 15:785-95. [PMID: 17201771 DOI: 10.1111/j.1365-2583.2006.00683.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Ecdysteroid regulation of gene transcription in Drosophila melanogaster and other insects is mediated by a heterodimer comprised of Ultraspiracle (USP) and one of three ecdysone receptor (EcR) isoforms (A, B1 and B2). This study revealed that the EcR/USP heterodimer displays isoform-specific capabilities. EcRB1 is normally induced with a form of USP that is missing its DNA-binding domain (DBD), although potentiation by juvenile hormone (JH) III is reduced. The EcRA and B2 isoforms, however, display almost no response to ecdysteroids with the DBD(-) USP. A mutation, K497E, in the shared ligand-binding domain of the EcR isoforms caused elevated EcRB2-specific affinity for a canonical ecdysone response element. The effects of directed modification and mutagenesis offer a strategy for developing hypotheses and considerations for studying in vivo function.
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Affiliation(s)
- J Beatty
- Center for Biotechnology, Genomics and Health Research, University of North Carolina-Greensboro, Greensboro, NC 27402-6170, USA
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Wilson TG, Wang S, Beno M, Farkas R. Wide mutational spectrum of a gene involved in hormone action and insecticide resistance in Drosophila melanogaster. Mol Genet Genomics 2006; 276:294-303. [PMID: 16802158 DOI: 10.1007/s00438-006-0138-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2006] [Accepted: 05/23/2006] [Indexed: 11/27/2022]
Abstract
The Methoprene-tolerant (Met) bHLH-PAS gene in Drosophila melanogaster is involved in the molecular action of juvenile hormone (JH), and mutants result in resistance to the toxic and morphogenetic effects of JH and JH agonist insecticides such as methoprene. A detailed study of Met mutants can shed light on the poorly understood action of JH as well as the molecular basis of Met resistance to JH insecticides. Nine mutant alleles bearing point mutations in Met were examined for penetrance and expressivity of three phenotypic characters: resistance, defective oogenesis, and a novel eye defect. The collection ranged from two weak alleles having less severe phenotypes to strong alleles with severe phenotypes similar to that of a null allele. The point mutations were located in both conserved and nonconserved domains. Both the eye defect, seen as severely malformed ommatidial facets in the posterior margin of the compound eye, and the oogenesis phenotype are nonconditional, whereas expression of the resistance phenotype requires treatment with JH or JH analogs (JHAs) during early metamorphosis. A proposed basis for all the phenotypic characters centers on MET action as a transcriptional regulator of ecdysone secondary-response target genes during metamorphosis. Disruption of MET function either by mutation or by JHA presence during early metamorphosis results in transcriptional misregulation of different target genes, resulting in the pathology seen in either instance. The variety of amino acid changes in MET that resulted in resistance may portend a rapid rise in resistance in response to increased use of JH insecticides in field insect populations.
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Affiliation(s)
- Thomas G Wilson
- Department of Entomology, Ohio State University, Columbus, OH 43210, USA.
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Godlewski J, Wang S, Wilson TG. Interaction of bHLH-PAS proteins involved in juvenile hormone reception in Drosophila. Biochem Biophys Res Commun 2006; 342:1305-11. [PMID: 16516852 DOI: 10.1016/j.bbrc.2006.02.097] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2006] [Accepted: 02/17/2006] [Indexed: 11/29/2022]
Abstract
The Methoprene-tolerant (Met) bHLH-PAS gene is involved in juvenile hormone (JH) action in Drosophila melanogaster as a likely component of a JH receptor. We expressed Met in Drosophila S2 cells and explored for MET partners using pull-down assays. MET-MET interaction was found to occur. The germ-cell expressed (gce) gene is another D. melanogaster bHLH-PAS gene with high homology to Met, and GCE formed heterodimers with MET. In the presence of JH or either of two JH agonists, MET-MET and MET-GCE formation was drastically reduced. Interaction between GCE and MET having N- or C-terminus truncations, bHLH or PAS-A domain deletions, or a point mutation in the PAS-B domain failed to occur. However, JH-dependent interaction occurred between GCE and MET having point mutations in bHLH or PAS-A. During development, changes in JH titer may alter partner binding by MET and result in different gene expression patterns.
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Affiliation(s)
- Jakub Godlewski
- Department of Entomology, 400 Aronoff Laboratory, Ohio State University, Columbus, OH 43210, USA
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