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Tao C, Li J, Du W, Qin X, Cao J, Liu C, Cheng T. Broad Complex-Z2 directly activates BmMBF2 to inhibit the silk protein synthesis in the silkworm, Bombyx mori. Int J Biol Macromol 2024; 277:134211. [PMID: 39069049 DOI: 10.1016/j.ijbiomac.2024.134211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 06/27/2024] [Accepted: 07/25/2024] [Indexed: 07/30/2024]
Abstract
Silk proteins, as natural macromolecules, have extensive applications in biomaterials and biomedicine. In the silkworm, the expression of silk protein genes is negatively associated with ecdysone during the molt stage, while it is positively correlated with juvenile hormone during the intermolt stage. In our previous study, overexpression of an isoform Z2 of Broad Complex (BmBrC-Z2), an ecdysone early response factor, significantly reduced the expression of silk protein genes. However, the underlying regulatory mechanism remains unclear. In this study, we conducted transcriptomic analysis and found that overexpressing BmBrC-Z2 significantly upregulated the expression level of multiprotein bridging factor 2 (BmMBF2), an inhibitor of fibroin heavy chain (FibH). Further investigations revealed that BmBrC-Z2 directly regulated BmMBF2 by binding to cis-regulatory elements, as demonstrated using Dual-Luciferase Reporter Gene Assay, EMSA, and ChIP-PCR assay. Additionally, when using the CRISPR/Cas9 system to knock out BmMBF2, silk protein genes were significantly upregulated during the molt stage of mutant larvae. These findings uncover the negative regulation of silk protein synthesis by the ecdysone signaling cascade, specifically through the manipulation of BmMBF2 expression during the molt stage. This study enhances to our understanding of the temporal regulatory mechanism governing silk protein synthesis and offers a potential strategy for improving silk yield.
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Affiliation(s)
- Cuicui Tao
- State Key Laboratory of Resource Insects, Southwest University, Chongqing 400715, China
| | - Jiaojiao Li
- State Key Laboratory of Resource Insects, Southwest University, Chongqing 400715, China
| | - Wenjie Du
- State Key Laboratory of Resource Insects, Southwest University, Chongqing 400715, China
| | - Xiaodan Qin
- State Key Laboratory of Resource Insects, Southwest University, Chongqing 400715, China
| | - Jun Cao
- State Key Laboratory of Resource Insects, Southwest University, Chongqing 400715, China
| | - Chun Liu
- State Key Laboratory of Resource Insects, Southwest University, Chongqing 400715, China.
| | - Tingcai Cheng
- State Key Laboratory of Resource Insects, Southwest University, Chongqing 400715, China.
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2
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Erezyilmaz D. The genetic determination of alternate stages in polyphenic insects. Evol Dev 2024:e12485. [PMID: 38867484 DOI: 10.1111/ede.12485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 02/23/2024] [Accepted: 05/14/2024] [Indexed: 06/14/2024]
Abstract
Molt-based transitions in form are a central feature of insect life that have enabled adaptation to diverse and changing environments. The endocrine regulation of these transitions is well established, but an understanding of their genetic regulation has only recently emerged from insect models. The pupal and adult stages of metamorphosing insects are determined by the stage specifying transcription factors broad-complex (br) and Ecdysone inducible protein 93 (E93), respectively. A probable larval determinant, chronologically inappropriate metamorphosis (chinmo), has just recently been characterized. Expression of these three transcription factors in the metamorphosing insects is regulated by juvenile hormone with ecdysteroid hormones, and by mutual repression between the stage-specific transcription factors. This review explores the hypothesis that variations in the onset, duration, and tissue-specific expression of chinmo, br, and E93 underlie other polyphenisms that have arisen throughout insects, including the castes of social insects, aquatic stages of mayflies, and the neoteny of endoparasites. The mechanisms that constrain how chinmo, br, and E93 expression may vary will also constrain the ways that insect life history may evolve. I find that four types of expression changes are associated with novel insect forms: (1) heterochronic shift in the turnover of expression, (2) expansion or contraction of expression, (3) tissue-specific expression, and (4) redeployment of stage-specific expression. While there is more to be learned about chinmo, br, and E93 function in diverse insect taxa, the studies outlined here show that insect stages are modular units in developmental time and a substrate for evolutionary forces to act upon.
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Affiliation(s)
- Deniz Erezyilmaz
- Department of Physiology, Anatomy and Genetics, Centre for Neural Circuits and Behavior, University of Oxford, Oxford, UK
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3
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Khong H, Hattley KB, Suzuki Y. The BTB transcription factor, Abrupt, acts cooperatively with Chronologically inappropriate morphogenesis (Chinmo) to repress metamorphosis and promotes leg regeneration. Dev Biol 2024; 509:70-84. [PMID: 38373692 DOI: 10.1016/j.ydbio.2024.02.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 02/07/2024] [Accepted: 02/16/2024] [Indexed: 02/21/2024]
Abstract
Many insects undergo the process of metamorphosis when larval precursor cells begin to differentiate to create the adult body. The larval precursor cells retain stem cell-like properties and contribute to the regenerative ability of larval appendages. Here we demonstrate that two Broad-complex/Tramtrack/Bric-à-brac Zinc-finger (BTB) domain transcription factors, Chronologically inappropriate morphogenesis (Chinmo) and Abrupt (Ab), act cooperatively to repress metamorphosis in the flour beetle, Tribolium castaneum. Knockdown of chinmo led to precocious development of pupal legs and antennae. We show that although topical application of juvenile hormone (JH) prevents the decrease in chinmo expression in the final instar, chinmo and JH act in distinct pathways. Another gene encoding the BTB domain transcription factor, Ab, was also necessary for the suppression of broad (br) expression in T. castaneum in a chinmo RNAi background, and simultaneous knockdown of ab and chinmo led to the precocious onset of metamorphosis. Furthermore, knockdown of ab led to the loss of regenerative potential of larval legs independently of br. In contrast, chinmo knockdown larvae exhibited pupal leg regeneration when a larval leg was ablated. Taken together, our results show that both ab and chinmo are necessary for the maintenance of the larval tissue identity and, apart from its role in repressing br, ab acts as a crucial regulator of larval leg regeneration. Our findings indicate that BTB domain proteins interact in a complex manner to regulate larval and pupal tissue homeostasis.
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Affiliation(s)
- Hesper Khong
- Department of Biological Sciences, Wellesley College, 106 Central St., Wellesley, MA, 02481, USA
| | - Kayli B Hattley
- Department of Biological Sciences, Wellesley College, 106 Central St., Wellesley, MA, 02481, USA
| | - Yuichiro Suzuki
- Department of Biological Sciences, Wellesley College, 106 Central St., Wellesley, MA, 02481, USA.
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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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He Q, Fan X, Wang S, Chen S, Chen J. Juvenile hormone inhibits adult cuticle formation in Drosophila melanogaster through Kr-h1/Dnmt2-mediated DNA methylation of Acp65A promoter. INSECT MOLECULAR BIOLOGY 2024; 33:124-135. [PMID: 37916965 DOI: 10.1111/imb.12884] [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: 08/26/2023] [Accepted: 10/08/2023] [Indexed: 11/03/2023]
Abstract
Differentiation of imaginal epidermal cells of Drosophila melanogaster to form adult cuticles occurs at approximately 40-93 h after puparium formation. Juvenile hormone (JH) given at pupariation results in formation of a second pupal cuticle in the abdomen instead of the adult cuticle. Although the adult cuticle gene Acp65A has been reported to be down-regulated following JH treatment, the regulatory mechanism remains unclear. Here, we found that the JH primary response gene Krüppel homologue 1 (Kr-h1) plays a vital role in the repression of adult cuticle formation through the mediation of JH action. Overexpression of Kr-h1 mimicked-while knocking down of Kr-h1 attenuated-the inhibitory action of JH on the formation of the adult abdominal cuticle. Further, we found that Kr-h1 inhibited the transcription of Acp65A by directly binding to the consensus Kr-h1 binding site (KBS) within the Acp65A promoter region. Moreover, the DNA methyltransferase Dnmt2 was shown to interact with Kr-h1, combined with the KBS to promote the DNA methylation of sequences around the KBS, in turn inhibiting the transcription of Acp65A. This study advances our understanding of the molecular basis of the "status quo" action of JH on the Drosophila adult metamorphosis.
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Affiliation(s)
- Qianyu He
- College of Life Science and Biotechnology, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Xiaochun Fan
- College of Life Science and Biotechnology, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Shunxin Wang
- College of Life Science and Biotechnology, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Shanshan Chen
- College of Life Science and Biotechnology, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Jinxia Chen
- College of Life Science and Biotechnology, Heilongjiang Bayi Agricultural University, Daqing, China
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6
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Xiong P, Wang WW, Liu XS, Wang YF, Wang JL. A CTL - Lys immune function maintains insect metamorphosis by preventing gut bacterial dysbiosis and limiting opportunistic infections. BMC Biol 2024; 22:54. [PMID: 38448930 PMCID: PMC10918859 DOI: 10.1186/s12915-024-01855-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 02/27/2024] [Indexed: 03/08/2024] Open
Abstract
BACKGROUND Gut bacteria are beneficial to the host, many of which must be passed on to host offspring. During metamorphosis, the midgut of holometabolous insects undergoes histolysis and remodeling, and thus risks losing gut bacteria. Strategies employed by holometabolous insects to minimize this risk are obscure. How gut bacteria affect host insects after entering the hemocoel and causing opportunistic infections remains largely elusive. RESULTS We used holometabolous Helicoverpa armigera as a model and found low Lactobacillus load, high level of a C-type lectin (CTL) gene CD209 antigen-like protein 2 (CD209) and its downstream lysozyme 1 (Lys1) in the midgut of the wandering stage. CD209 or Lys1 depletion increased the load of midgut Lactobacillus, which further translocate to the hemocoel. In particular, CD209 or Lys1 depletion, injection of Lactobacillus plantarum, or translocation of midgut L. plantarum into the hemocoel suppressed 20-hydroxyecdysone (20E) signaling and delayed pupariation. Injection of L. plantarum decreased triacylglycerol and cholesterol storage, which may result in insufficient energy and 20E available for pupariation. Further, Lysine-type peptidoglycan, the major component of gram-positive bacterial cell wall, contributed to delayed pupariation and decreased levels of triacylglycerols, cholesterols, and 20E, in both H. armigera and Drosophila melanogaster. CONCLUSIONS A mechanism by which (Lactobacillus-induced) opportunistic infections delay insect metamorphosis was found, namely by disturbing the homeostasis of lipid metabolism and reducing 20E production. Moreover, the immune function of CTL - Lys was characterized for insect metamorphosis by maintaining gut homeostasis and limiting the opportunistic infections.
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Affiliation(s)
- Pei Xiong
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
| | - Wen-Wen Wang
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
| | - Xu-Sheng Liu
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
| | - Yu-Feng Wang
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
| | - Jia-Lin Wang
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China.
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7
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Morrow H, Mirth CK. Timing Drosophila development through steroid hormone action. Curr Opin Genet Dev 2024; 84:102148. [PMID: 38271845 DOI: 10.1016/j.gde.2023.102148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 12/15/2023] [Accepted: 12/15/2023] [Indexed: 01/27/2024]
Abstract
Specifically timed pulses of the moulting hormone ecdysone are necessary for developmental progression in insects, guiding development through important milestones such as larval moults, pupation and metamorphosis. It also coordinates the acquisition of cell identities, known as cell patterning, and growth in a tissue-specific manner. In the absence of ecdysone, the ecdysone receptor heterodimer Ecdysone Receptor and Ultraspiracle represses expression of target primary response genes, which become de-repressed as the ecdysone titre rises. However, ecdysone signalling elicits both repressive and activating responses in a temporal and tissue-specific manner. To understand how ecdysone achieves such specificity, this review explores the layers of gene regulation involved in stage-appropriate ecdysone responses in Drosophila fruit flies.
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Affiliation(s)
- Hannah Morrow
- School of Biological Sciences, Monash University, Clayton, Victoria 3000, Australia.
| | - Christen K Mirth
- School of Biological Sciences, Monash University, Clayton, Victoria 3000, Australia
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8
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Zhang S, Wu S, Yao R, Wei X, Ohlstein B, Guo Z. Eclosion muscles secrete ecdysteroids to initiate asymmetric intestinal stem cell division in Drosophila. Dev Cell 2024; 59:125-140.e12. [PMID: 38096823 DOI: 10.1016/j.devcel.2023.11.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 10/05/2023] [Accepted: 11/14/2023] [Indexed: 01/11/2024]
Abstract
During organ development, tissue stem cells first expand via symmetric divisions and then switch to asymmetric divisions to minimize the time to obtain a mature tissue. In the Drosophila midgut, intestinal stem cells switch their divisions from symmetric to asymmetric at midpupal development to produce enteroendocrine cells. However, the signals that initiate this switch are unknown. Here, we identify the signal as ecdysteroids. In the presence of ecdysone, EcR and Usp promote the expression of E93 to suppress Br expression, resulting in asymmetric divisions. Surprisingly, the primary source of pupal ecdysone is not from the prothoracic gland but from dorsal internal oblique muscles (DIOMs), a group of transient skeletal muscles that are required for eclosion. Genetic analysis shows that DIOMs secrete ecdysteroids during mTOR-mediated muscle remodeling. Our findings identify sequential endocrine and mechanical roles for skeletal muscle, which ensure the timely asymmetric divisions of intestinal stem cells.
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Affiliation(s)
- Song Zhang
- Department of Medical Genetics, School of Basic Medicine, Institute for Brain Research, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Song Wu
- Department of Medical Genetics, School of Basic Medicine, Institute for Brain Research, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Ruining Yao
- Department of Medical Genetics, School of Basic Medicine, Institute for Brain Research, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Xueying Wei
- Department of Medical Genetics, School of Basic Medicine, Institute for Brain Research, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Benjamin Ohlstein
- Children's Research Institute and Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Zheng Guo
- Department of Medical Genetics, School of Basic Medicine, Institute for Brain Research, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; Cell Architecture Research Center, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China.
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9
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Fine JD, Cox-Foster DL, Moor KJ, Chen R, Avalos A. Trisiloxane Surfactants Negatively Affect Reproductive Behaviors and Enhance Viral Replication in Honey Bees. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2024; 43:222-233. [PMID: 37861380 DOI: 10.1002/etc.5771] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 09/06/2023] [Accepted: 10/18/2023] [Indexed: 10/21/2023]
Abstract
Trisiloxane surfactants are often applied in formulated adjuvant products to blooming crops, including almonds, exposing the managed honey bees (Apis mellifera) used for pollination of these crops and persisting in colony matrices, such as bee bread. Despite this, little is known regarding the effects of trisiloxane surfactants on important aspects of colony health, such as reproduction. In the present study, we use laboratory assays to examine how exposure to field-relevant concentrations of three trisiloxane surfactants found in commonly used adjuvant formulations affect queen oviposition rates, worker interactions with the queen, and worker susceptibility to endogenous viral pathogens. Trisiloxane surfactants were administered at 5 mg/kg in pollen supplement diet for 14 days. No effects on worker behavior or physiology could be detected, but our results demonstrate that hydroxy-capped trisiloxane surfactants can negatively affect queen oviposition and methyl-capped trisiloxane surfactants cause increased replication of Deformed Wing Virus in workers, suggesting that trisiloxane surfactant use while honey bees are foraging may negatively impact colony longevity and growth. Environ Toxicol Chem 2024;43:222-233. © 2023 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.
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Affiliation(s)
- Julia D Fine
- US Department of Agriculture-Agricultural Research Service Invasive Species and Pollinator Health Research Unit, Davis, California, USA
| | - Diana L Cox-Foster
- US Department of Agriculture-Agricultural Research Service Pollinating Insect Research Unit, Logan, Utah, USA
| | - Kyle J Moor
- Utah Water Research Laboratory, Department of Civil and Environmental Engineering, Utah State University, Logan, Utah, USA
| | - Ruiwen Chen
- Department of Civil and Environmental Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Arian Avalos
- US Department of Agriculture-Agricultural Research Service Honey Bee Breeding, Genetics, and Physiology Research Laboratory, Baton Rouge, Louisiana, USA
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Yu R, Zhang W, Li Y, Tang J, Kim K, Li B. Functional characterisation of Fe (II) and 2OG-dependent dioxygenase TcALKBH4 in the red flour beetle, Tribolium castaneum. INSECT MOLECULAR BIOLOGY 2023; 32:676-688. [PMID: 37462221 DOI: 10.1111/imb.12865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Accepted: 07/03/2023] [Indexed: 11/08/2023]
Abstract
Alpha-ketoglutarate-dependent dioxygenase ALKB homologue 4 (ALKBH4) is a member of the Fe (II) and 2-oxoglutarate-dependent ALKB homologue family that plays important roles in epigenetic regulation by alkyl lesions removal in mammals. However, the roles of ALKBH4 in insects are not clear. Here, TcALKBH4 was cloned and functionally characterised in Tribolium castaneum. Temporal expression revealed that TcALKBH4 was highly expressed in early embryos and early pupae. Spatial expression showed that TcALKBH4 was highly expressed in the adult testis, and followed by the ovary. RNA interference targeting TcALKBH4 at different developmental stages in T. castaneum led to apparent phenotypes including the failure of development in larvae, the reduction of food intake and the deficiency of fertility in adult. However, further dot blot analyses showed that TcALKBH4 RNAi does not seem to influence 6 mA levels in vivo. qRT-PCR was used to further explore the underlying molecular mechanisms; the result showed that TcALKBH4 mediates the development of larvae possibly through 20E signalling pathway, and the fertility of female and male adult might be regulated by the expression of vitellogenesis and JH signalling pathway, respectively. Altogether, these findings will provide new insights into the potential function of ALKBH4 in insects.
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Affiliation(s)
- Runnan Yu
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Wenjing Zhang
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Yanxiao Li
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Jing Tang
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - KumChol Kim
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
- Department of Life-Science, University of Science, Pyongyang, Democratic People's Republic of Korea
| | - Bin Li
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
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Seth RK, Yadav P, Reynolds SE. Dichotomous sperm in Lepidopteran insects: a biorational target for pest management. FRONTIERS IN INSECT SCIENCE 2023; 3:1198252. [PMID: 38469506 PMCID: PMC10926456 DOI: 10.3389/finsc.2023.1198252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 07/31/2023] [Indexed: 03/13/2024]
Abstract
Lepidoptera are unusual in possessing two distinct kinds of sperm, regular nucleated (eupyrene) sperm and anucleate (apyrene) sperm ('parasperm'). Sperm of both types are transferred to the female and are required for male fertility. Apyrene sperm play 'helper' roles, assisting eupyrene sperm to gain access to unfertilized eggs and influencing the reproductive behavior of mated female moths. Sperm development and behavior are promising targets for environmentally safer, target-specific biorational control strategies in lepidopteran pest insects. Sperm dimorphism provides a wide window in which to manipulate sperm functionality and dynamics, thereby impairing the reproductive fitness of pest species. Opportunities to interfere with spermatozoa are available not only while sperm are still in the male (before copulation), but also in the female (after copulation, when sperm are still in the male-provided spermatophore, or during storage in the female's spermatheca). Biomolecular technologies like RNAi, miRNAs and CRISPR-Cas9 are promising strategies to achieve lepidopteran pest control by targeting genes directly or indirectly involved in dichotomous sperm production, function, or persistence.
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Affiliation(s)
- Rakesh K. Seth
- Department of Zoology, University of Delhi, Delhi, India
| | - Priya Yadav
- Department of Zoology, University of Delhi, Delhi, India
| | - Stuart E. Reynolds
- Department of Life Sciences, University of Bath, Bath, United Kingdom
- Milner Centre for Evolution, University of Bath, Bath, United Kingdom
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12
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Bailly TPM, Kohlmeier P, Etienne RS, Wertheim B, Billeter JC. Social modulation of oogenesis and egg laying in Drosophila melanogaster. Curr Biol 2023:S0960-9822(23)00750-9. [PMID: 37369209 DOI: 10.1016/j.cub.2023.05.074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 02/02/2023] [Accepted: 05/31/2023] [Indexed: 06/29/2023]
Abstract
Being part of a group facilitates cooperation between group members but also creates competition for resources. This is a conundrum for gravid females, whose future offspring benefit from being in a group only if there are enough resources relative to group size. Females may therefore be expected to modulate reproductive output depending on social context. In the fruit fly Drosophila melanogaster, females actively attract conspecifics to lay eggs on the same resources, generating groups in which individuals may cooperate or compete. The genetic tractability of this species allows dissecting the mechanisms underlying physiological adaptation to social context. Here, we show that females produce eggs increasingly faster as group size increases. By laying eggs faster when grouped than when isolated, females reduce competition between offspring and increase offspring survival. In addition, grouped females lay eggs during the day, while isolated females lay them at night. We show that responses to the presence of others requires visual input and that flies from any sex, mating status, or species can trigger these responses. The mechanisms of this modulation of egg laying by group is connected to a lifting of the inhibition of light on oogenesis and egg laying, possibly mediated in part by an increase in juvenile hormone activity. Because modulation of reproduction by social context is a hallmark of animals with higher levels of sociality, our findings in a species considered solitary question the validity of this nomenclature and suggest a widespread and profound influence of social context on reproduction.
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Affiliation(s)
- Tiphaine P M Bailly
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9474AG Groningen, the Netherlands
| | - Philip Kohlmeier
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9474AG Groningen, the Netherlands; University of Memphis, Department of Biological Sciences, Memphis, TN 38152-3530, USA
| | - Rampal S Etienne
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9474AG Groningen, the Netherlands
| | - Bregje Wertheim
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9474AG Groningen, the Netherlands
| | - Jean-Christophe Billeter
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9474AG Groningen, the Netherlands.
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13
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He Q, Hou T, Fan X, Wang S, Wang Y, Chen S. Juvenile hormone suppresses sensory organ precursor determination to block Drosophila adult abdomen morphogenesis. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2023; 157:103957. [PMID: 37192726 DOI: 10.1016/j.ibmb.2023.103957] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 05/05/2023] [Accepted: 05/05/2023] [Indexed: 05/18/2023]
Abstract
Juvenile hormone (JH) has a classic "status quo" action at both the pupal and adult molts when administrated exogenously. In Drosophila, treatment with JH at pupariation inhibits the formation of abdominal bristles, which are derived from the histoblasts. However, the mechanism via which JH exerts this effect remains poorly understood. In this study, we analyzed the effect of JH on histoblast proliferation, migration, and differentiation. Our results indicated that whereas the proliferation and migration of histoblasts remained unaffected following treatment with a JH mimic (JHM), their differentiation, particularly the specification of sensor organ precursor (SOP) cells, was inhibited. This effect was attributable to downregulated proneural genes achaete (ac) and Scute (sc) expression levels, which prevented the specification of SOP cells in proneural clusters. Moreover, Kr-h1 was found to mediate this effect of JHM. Histoblast-specific overexpression or knockdown of Kr-h1, respectively mimicked or attenuated the effects exerted by JHM on abdominal bristle formation, SOP determination, and transcriptional regulation of ac and sc. These results indicated that the defective SOP determination was responsible for the inhibition of abdominal bristle formation by JHM, which, in turn, was mainly mediated via the transducing action of Kr-h1.
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Affiliation(s)
- Qianyu He
- College of Life Science and Biotechnology, Heilongjiang Bayi Agricultural University, Daqing, China.
| | - Tianlan Hou
- College of Life Science and Biotechnology, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Xiaochun Fan
- College of Life Science and Biotechnology, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Shunxin Wang
- College of Life Science and Biotechnology, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Yanhong Wang
- College of Life Science and Biotechnology, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Shanshan Chen
- College of Life Science and Biotechnology, Heilongjiang Bayi Agricultural University, Daqing, China
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14
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HDAC3 Knockdown Dysregulates Juvenile Hormone and Apoptosis-Related Genes in Helicoverpa armigera. Int J Mol Sci 2022; 23:ijms232314820. [PMID: 36499148 PMCID: PMC9740019 DOI: 10.3390/ijms232314820] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/03/2022] [Accepted: 11/18/2022] [Indexed: 12/05/2022] Open
Abstract
Insect development requires genes to be expressed in strict spatiotemporal order. The dynamic regulation of genes involved in insect development is partly orchestrated by the histone acetylation-deacetylation via histone acetyltransferases (HATs) and histone deacetylases (HDACs). Although histone deacetylase 3 (HDAC3) is required for mice during early embryonic development, its functions in Helicoverpa armigera (H. armigera) and its potential to be used as a target of insecticides remain unclear. We treated H. armigera with HDAC3 siRNA and RGFP966, a specific inhibitor, examining how the HDAC3 loss-of-function affects growth and development. HDAC3 siRNA and RGFP966 treatment increased mortality at each growth stage and altered metamorphosis, hampering pupation and causing abnormal wing development, reduced egg production, and reduced hatching rate. We believe that the misregulation of key hormone-related genes leads to abnormal pupa development in HDAC3 knockout insects. RNA-seq analysis identified 2788 differentially expressed genes (≥two-fold change; p ≤ 0.05) between siHDAC3- and siNC-treated larvae. Krüppel homolog 1 (Kr-h1), was differentially expressed in HDAC3 knockdown larvae. Pathway-enrichment analysis revealed the significant enrichment of genes involved in the Hippo, MAPK, and Wnt signaling pathways following HDAC3 knockdown. Histone H3K9 acetylation was increased in H. armigera after siHDAC3 treatment. In conclusion, HDAC3 knockdown dysregulated juvenile hormone (JH)-related and apoptosis-related genes in H. armigera. The results showed that the HDAC3 gene is a potential target for fighting H. armigera.
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15
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Jia D, Jevitt A, Huang YC, Ramos B, Deng WM. Developmental regulation of epithelial cell cuboidal-to-squamous transition in Drosophila follicle cells. Dev Biol 2022; 491:113-125. [PMID: 36100084 DOI: 10.1016/j.ydbio.2022.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 08/29/2022] [Accepted: 09/06/2022] [Indexed: 11/24/2022]
Abstract
Epithelial cells form continuous membranous structures for organ formation, and these cells are classified into three major morphological categories: cuboidal, columnar, and squamous. It is crucial that cells transition between these shapes during the morphogenetic events of organogenesis, yet this process remains poorly understood. All three epithelial cell shapes can be found in the follicular epithelium of Drosophila egg chamber during oogenesis. Squamous cells (SCs) are initially restricted to the anterior terminus in cuboidal shape. They then rapidly become flattened to assume squamous shape by stretching and expansion in 12 h during midoogenesis. Previously, we reported that Notch signaling activated a zinc-finger transcription factor Broad (Br) at the end of early oogenesis. Here we report that ecdysone and JAK/STAT pathways subsequently converge on Br to serve as an important spatiotemporal regulator of this dramatic morphological change of SCs. The early uniform pattern of Br in the follicular epithelium is directly established by Notch signaling at stage 5 of oogenesis. Later, ecdysone and JAK/STAT signaling activities synergize to suppress Br in SCs from stage 8 to 10a, contributing to proper SC squamous shape. During this process, ecdysone signaling is essential for SC stretching, while JAK/STAT regulates SC clustering and cell fate determination. This study reveals an inhibitory role of ecdysone signaling in suppressing Br in epithelial cell remodeling. In this study we also used single-cell RNA sequencing data to highlight the shift in gene expression which occurs as Br is suppressed and cells become flattened.
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Affiliation(s)
- Dongyu Jia
- Department of Biology, Georgia Southern University, Statesboro, GA, 30460, USA; Department of Biological Science, Florida State University, Tallahassee, FL, 32306, USA.
| | - Allison Jevitt
- Department of Biological Science, Florida State University, Tallahassee, FL, 32306, USA; Cell Cycle and Cancer Biology Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Yi-Chun Huang
- Department of Biochemistry and Molecular Biology, Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA, 70112, USA
| | - Belen Ramos
- Department of Biology, Georgia Southern University, Statesboro, GA, 30460, USA
| | - Wu-Min Deng
- Department of Biological Science, Florida State University, Tallahassee, FL, 32306, USA; Department of Biochemistry and Molecular Biology, Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA, 70112, USA.
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16
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He Q, Zhang Y. Kr-h1, a Cornerstone Gene in Insect Life History. Front Physiol 2022; 13:905441. [PMID: 35574485 PMCID: PMC9092015 DOI: 10.3389/fphys.2022.905441] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Accepted: 04/13/2022] [Indexed: 11/13/2022] Open
Abstract
Insect life cycle is coordinated by hormones and their downstream effectors. Krüppel homolog1 (Kr-h1) is one of the crucial effectors which mediates the actions of the two critical hormones of insects, the juvenile hormone (JH) and 20-hydroxyecdysone (20E). It is a transcription factor with a DNA-binding motif of eight C2H2 zinc fingers which is found to be conserved among insect orders. The expression of Kr-h1 is fluctuant during insect development with high abundance in juvenile instars and lower levels in the final instar and pupal stage, and reappearance in adults, which is governed by the coordination of JH, 20E, and miRNAs. The dynamic expression pattern of Kr-h1 is closely linked to its function in the entire life of insects. Over the past several years, accumulating studies have advanced our understanding of the role of Kr-h1 during insect development. It acts as a universal antimetamorphic factor in both hemimetabolous and holometabolous species by directly inhibiting the transcription of 20E signaling genes Broad-Complex (Br-C) and Ecdysone induced protein 93F (E93), and steroidogenic enzyme genes involved in ecdysone biosynthesis. Meanwhile, it promotes vitellogenesis and ovarian development in the majority of studied insects. In addition, Kr-h1 regulates insect behavioral plasticity and caste identity, neuronal morphogenesis, maturation of sexual behavior, as well as embryogenesis and metabolic homeostasis. Hence, Kr-h1 acts as a cornerstone regulator in insect life.
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Affiliation(s)
- Qianyu He
- Heilongjiang Provincial Key Laboratory of Environmental Microbiology and Recycling of Argo-Waste in Cold Region, College of Life Science and Biotechnology, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Yuanxi Zhang
- Daqing Municipal Ecology and Environment Bureau, Daqing, China
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Chinmo is the larval member of the molecular trinity that directs Drosophila metamorphosis. Proc Natl Acad Sci U S A 2022; 119:e2201071119. [PMID: 35377802 PMCID: PMC9169713 DOI: 10.1073/pnas.2201071119] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The genome of insects with complete metamorphosis contains the instructions for making three distinct body forms, that of the larva, of the pupa, and of the adult. However, the molecular mechanisms by which each gene set is called forth and stably expressed are poorly understood. A half century ago, it was proposed that there was a set of three master genes that inhibited each other’s expression and enabled the expression of genes for each respective stage. We show that the transcription factor chinmo is essential for maintaining the larval stage in Drosophila, and with two other regulatory genes, broad and E93, makes up the trinity of mutually repressive master genes that underlie insect metamorphosis. The molecular control of insect metamorphosis from larva to pupa to adult has long been a mystery. The Broad and E93 transcription factors, which can modify chromatin domains, are known to direct the production of the pupa and the adult, respectively. We now show that chinmo, a gene related to broad, is essential for the repression of these metamorphic genes. Chinmo is strongly expressed during the formation and growth of the larva and its removal results in the precocious expression of broad and E93 in the first stage larva, causing a shift from larval to premetamorphic functions. This trinity of Chinmo, Broad, and E93 regulatory factors is mutually inhibitory. The interaction of this network with regulatory hormones likely ensures the orderly progression through insect metamorphosis.
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18
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Sun YY, Fu DY, Liu B, Wang LJ, Chen H. Roles of Krüppel Homolog 1 and Broad-Complex in the Development of Dendroctonus armandi (Coleoptera: Scolytinae). Front Physiol 2022; 13:865442. [PMID: 35464080 PMCID: PMC9019567 DOI: 10.3389/fphys.2022.865442] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Accepted: 03/23/2022] [Indexed: 11/13/2022] Open
Abstract
In insects, metamorphosis is controlled by juvenile hormone (JH) and 20-hydroxyecdysone (20E). Krüppel homolog 1 (Kr-h1), a key JH-early inducible gene, is responsible for the suppression of metamorphosis and the regulation of the Broad-Complex (Br-C) gene, which is induced by 20E and functions as a “pupal specifier”. In this study, we identified and characterized the expression patterns and tissue distribution of DaKr-h1 and DaBr-C at various developmental stages of Dendroctonus armandi. The expression of the two genes was induced by JH analog (JHA) methoprene and 20E, and their functions were investigated by RNA interference. DaKr-h1 and DaBr-C were predominantly expressed in the heads of larvae and were significantly downregulated during the molting stage. In contrast, the DaKr-h1 transcript level was highest in the adult anterior midgut. DaBr-C was mainly expressed in female adults, with the highest transcript levels in the ovaries. In the larval and pupal stages, both JHA and 20E significantly induced DaKr-h1, but only 20E significantly induced DaBr-C, indicating the importance of hormones in metamorphosis. DaKr-h1 knockdown in larvae upregulated DaBr-C expression, resulting in precocious metamorphosis from larvae to pupae and the formation of miniature pupae. DaKr-h1 knockdown in pupae suppressed DaBr-C expression, increased emergence, caused abnormal morphology, and caused the formation of small-winged adults. These results suggest that DaKr-h1 is required for the metamorphosis of D. armandi. Our findings provide insight into the roles of DaKr-h1 and DaBr-C in JH-induced transcriptional repression and highlight DaKr-h1 as a potential target for metamorphosis suppression in D. armandi.
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Affiliation(s)
- Ya-Ya Sun
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
- College of Forestry, Northwest A&F University, Xianyang, China
| | - Dan-Yang Fu
- College of Forestry, Northwest A&F University, Xianyang, China
| | - Bin Liu
- College of Forestry, Northwest A&F University, Xianyang, China
| | - Lin-Jun Wang
- College of Forestry, Northwest A&F University, Xianyang, China
| | - Hui Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
- *Correspondence: Hui Chen,
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19
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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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Nunes C, Koyama T, Sucena É. Co-option of immune effectors by the hormonal signalling system triggering metamorphosis in Drosophila melanogaster. PLoS Genet 2021; 17:e1009916. [PMID: 34843450 PMCID: PMC8659296 DOI: 10.1371/journal.pgen.1009916] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 12/09/2021] [Accepted: 10/29/2021] [Indexed: 11/24/2022] Open
Abstract
Insect metamorphosis is triggered by the production, secretion and degradation of 20-hydroxyecdysone (ecdysone). In addition to its role in developmental regulation, increasing evidence suggests that ecdysone is involved in innate immunity processes, such as phagocytosis and the induction of antimicrobial peptide (AMP) production. AMP regulation includes systemic responses as well as local responses at surface epithelia that contact with the external environment. At pupariation, Drosophila melanogaster increases dramatically the expression of three AMP genes, drosomycin (drs), drosomycin-like 2 (drsl2) and drosomycin-like 5 (drsl5). We show that the systemic action of drs at pupariation is dependent on ecdysone signalling in the fat body and operates via the ecdysone downstream target, Broad. In parallel, ecdysone also regulates local responses, specifically through the activation of drsl2 expression in the gut. Finally, we confirm the relevance of this ecdysone dependent AMP expression for the control of bacterial load by showing that flies lacking drs expression in the fat body have higher bacterial persistence over metamorphosis. In contrast, local responses may be redundant with the systemic effect of drs since reduction of ecdysone signalling or of drsl2 expression has no measurable negative effect on bacterial load control in the pupa. Together, our data emphasize the importance of the association between ecdysone signalling and immunity using in vivo studies and establish a new role for ecdysone at pupariation, which impacts developmental success by regulating the immune system in a stage-dependent manner. We speculate that this co-option of immune effectors by the hormonal system may constitute an anticipatory mechanism to control bacterial numbers in the pupa, at the core of metamorphosis evolution.
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Affiliation(s)
- Catarina Nunes
- Evolution and Development Laboratory, Instituto Gulbenkian de Ciência, Oeiras, Portugal
| | - Takashi Koyama
- Section for Cell and Neurobiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Élio Sucena
- Evolution and Development Laboratory, Instituto Gulbenkian de Ciência, Oeiras, Portugal
- Departamento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
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21
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Suzuki Y, Shiotsuki T, Jouraku A, Miura K, Minakuchi C. Characterization of E93 in neometabolous thrips Frankliniella occidentalis and Haplothrips brevitubus. PLoS One 2021; 16:e0254963. [PMID: 34293026 PMCID: PMC8297894 DOI: 10.1371/journal.pone.0254963] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 07/07/2021] [Indexed: 11/19/2022] Open
Abstract
Insect metamorphosis into an adult occurs after the juvenile hormone (JH) titer decreases at the end of the juvenile stage. This generally coincides with decreased transcript levels of JH-response transcription factors Krüppel homolog 1 (Kr-h1) and broad (br), and increased transcript levels of the adult specifier E93. Thrips (Thysanoptera) develop through inactive and non-feeding stages referred to as “propupa” and “pupa”, and this type of distinctive metamorphosis is called neometaboly. To understand the mechanisms of hormonal regulation in thrips metamorphosis, we previously analyzed the transcript levels of Kr-h1 and br in two thrips species, Frankliniella occidentalis (Thripidae) and Haplothrips brevitubus (Phlaeothripidae). In both species, the transcript levels of Kr-h1 and br decreased in the “propupal” and “pupal” stages, and their transcription was upregulated by exogenous JH mimic treatment. Here we analyzed the developmental profiles of E93 in these two thrips species. Quantitative RT-PCR revealed that E93 expression started to increase at the end of the larval stage in F. occidentalis and in the “propupal” stage of H. brevitubus, as Kr-h1 and br mRNA levels decreased. Treatment with an exogenous JH mimic at the onset of metamorphosis prevented pupal-adult transition and caused repression of E93. These results indicated that E93 is involved in adult differentiation after JH titer decreases at the end of the larval stage of thrips. By comparing the expression profiles of Kr-h1, br, and E93 among insect species, we propose that the “propupal” and “pupal” stages of thrips have some similarities with the holometabolous prepupal and pupal stages, respectively.
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Affiliation(s)
- Youhei Suzuki
- Graduate School of Bio-Agricultural Sciences, Nagoya University, Nagoya, Japan
| | - Takahiro Shiotsuki
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Tsukuba, Japan
- Faculty of Life and Environmental Science, Shimane University, Matsue, Japan
| | - Akiya Jouraku
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Tsukuba, Japan
| | - Ken Miura
- Graduate School of Bio-Agricultural Sciences, Nagoya University, Nagoya, Japan
| | - Chieka Minakuchi
- Graduate School of Bio-Agricultural Sciences, Nagoya University, Nagoya, Japan
- * E-mail:
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22
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Identification of juvenile hormone-induced posttranslational modifications of methoprene tolerant and Krüppel homolog 1 in the yellow fever mosquito, Aedes aegypti. J Proteomics 2021; 242:104257. [PMID: 33957312 DOI: 10.1016/j.jprot.2021.104257] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 03/29/2021] [Accepted: 04/28/2021] [Indexed: 11/23/2022]
Abstract
Recent studies reported that JH-regulated phosphorylation status of the JH-receptor complex contributes to its transcription activity in Aedes aegypti. However, phosphorylation sites of these proteins have not yet been identified. In this study, we found that the fusion of an EGFP tag to Ae. aegypti Kr-h1 (AaKr-h1) and Met (AaMet) improved their stability in mosquito Aag-2 cells, which allowed their purification. The liquid chromatography and tandem mass spectrometry analysis of the purified AaKr-h1 showed that the phosphoserine residue at position 694, located in the evolutionarily conserved SVIQ motif, is dephosphorylated when the cells are exposed to JH. The AaKr-h1 dephosphorylation mutant (S694V) showed significantly higher activity in inducing the luciferase gene regulated by JH response elements. The phosphorylation profile of Met also changed after exposing Aag-2 cells to JH III. The Ser-77 and Ser-710 residues of Met were phosphorylated after JH III treatment. In contrast, the two phosphoserine residues at positions 73 and 747 were dephosphorylated after JH III treatment. JH exposure also induced transient and reversible phosphorylation of Thr-664 and Ser-723 residues. Overall, these data show that JH induces changes in post-translational modifications of AaMet and AaKr-h1. SIGNIFICANCE: Female Aedes aegypti mosquitoes are known to vector many disease agents, including Zika virus, dengue virus chikungunya virus, and Mayaro and yellow fever virus. In the present study, we developed an efficient method to prepare Ae. aegypti Met and Kr-h1, which are typically difficult to produce and purify, using a mosquito cell line expression system. A liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based approaches were utilized to map the phosphorylation profiles of the isolated proteins. We then monitored the changes induced by JH activation in the phosphorylation profiles to check if the JH modulates post-translation modification of its key transcription factors. We found that the JH induced alterations in the phosphorylation profiles of the multiple residues of AaMet. In contrast, activation of the JH signaling pathway was accompanied by dephosphorylation of AaKr-h1 at phosphoserine-694, increasing its transcriptional activity. In addition, S694 of AaKr-h1 was located in the RMSSVIQYA motif highly conserved in orthologous proteins from other insect species. These results can help us further understand how JH modulates its key transcription factors and provide a basis for the development of novel insect control strategies.
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Di YQ, Han XL, Kang XL, Wang D, Chen CH, Wang JX, Zhao XF. Autophagy triggers CTSD (cathepsin D) maturation and localization inside cells to promote apoptosis. Autophagy 2021; 17:1170-1192. [PMID: 32324083 PMCID: PMC8143247 DOI: 10.1080/15548627.2020.1752497] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 03/30/2020] [Accepted: 04/02/2020] [Indexed: 12/28/2022] Open
Abstract
CTSD/CathD/CATD (cathepsin D) is a lysosomal aspartic protease. A distinguishing characteristic of CTSD is its dual functions of promoting cell proliferation via secreting a pro-enzyme outside the cells as a ligand, and promoting apoptosis via the mature form of this enzyme inside cells; however, the regulation of its secretion, expression, and maturation is undetermined. Using the lepidopteran insect Helicoverpa armigera, a serious agricultural pest, as a model, we revealed the dual functions and regulatory mechanisms of CTSD secretion, expression, and maturation. Glycosylation of asparagine 233 (N233) determined pro-CTSD secretion. The steroid hormone 20-hydroxyecdysone (20E) promoted CTSD expression. Macroautophagy/autophagy triggered CTSD maturation and localization inside midgut cells to activate CASP3 (caspase 3) and promote apoptosis. Pro-CTSD was expressed in the pupal epidermis and was secreted into the hemolymph to promote adult fat body endoreplication/endoreduplication, cell proliferation, and association. Our study revealed that the differential expression and autophagy-mediated maturation of CTSD in tissues determine its roles in apoptosis and cell proliferation, thereby determining the cell fates of tissues during lepidopteran metamorphosis.Abbreviations: 20E: 20-hydroxyecdysone; 3-MA: 3-methyladenine; ACTB/β-actin: actin beta; AKT: protein kinase B; ATG1: autophagy-related 1; ATG4: autophagy-related 4; ATG5: autophagy-related 5; ATG7: autophagy-related 7; ATG14: autophagy-related 14; BSA: bovine serum albumin; CASP3: caspase 3; CQ: choroquine; CTSD: cathepsin D; DAPI: 4',6-diamidino-2-phenylindole; DMSO: dimethyl sulfoxide; DPBS: dulbecco's phosphate-buffered saline; DsRNA: double-stranded RNA; EcR: ecdysone receptor; EcRE: ecdysone response element; EdU: 5-ethynyl-2´-deoxyuridine; G-m-CTSD: glycosylated-mautre-CTSD; G-pro-CTSD: glycosylated-pro-CTSD; HaEpi: Helicoverpa armigera epidermal cell line; HE staining: hematoxylin and eosin staining; IgG: immunoglobin G; IM: imaginal midgut; JH: juvenile hormone; Kr-h1: krueppel homologous protein 1; LM: larval midgut; M6P: mannose-6-phosphate; PBS: phosphate-buffered saline; PCD: programmed cell death; PNGase: peptide-N-glycosidase F; RFP: red fluorescent protein; RNAi: RNA interference; SDS-PAGE: sodium dodecyl sulfate-polyacrylamide gel electrophoresis; SYX17: syntaxin 17; USP1: ultraspiracle isoform 1.
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Affiliation(s)
- Yu-Qin Di
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - Xiao-Lin Han
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - Xin-Le Kang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - Di Wang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - Cai-Hua Chen
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - Jin-Xing Wang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - Xiao-Fan Zhao
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
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Jeng ML, Suzuki Y, Chang CY, Chen TR. Do holometabolous insects molt spontaneously after adulthood? An exceptional case report in fireflies (Coleoptera: Lampyridae), with discussion of its inferred endocrine regulation especially in relation to neoteny. ARTHROPOD STRUCTURE & DEVELOPMENT 2021; 61:101013. [PMID: 33517027 DOI: 10.1016/j.asd.2020.101013] [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: 03/30/2020] [Revised: 11/19/2020] [Accepted: 11/19/2020] [Indexed: 06/12/2023]
Abstract
It has been a traditionally held view that winged insects stop molting after they reach adulthood. We observed a fascinating phenomenon of a post-imago molt occurring in the neotenic females of a firefly species in Taiwan over the last two years. By rearing Lamprigera minor larvae to adults, four out of the five unmated females studied were found undergoing an extra molt 8-18 days after adult eclosion. They were reproductively mature when the post-imago molt occurred, as evidenced by the eggs inside their bodies. The four females died without oviposition whereas the only normal female laid eggs. A comparison of exuviae of different stages confirmed the existence of post-imago ecdysis. The adult skin differed from the pupal one mainly in the mouthparts and leg structures. No mix of pupal and adult traits was seen in the adult skin. The females retained the same morphology after the extra molt. A close examination of the post-imago molting females revealed that their oviduct openings were all blocked by larval or pupal skin and thus unable to lay eggs. The reproductive stress may invoke an endocrine disorder and lead to an extra molt. We propose that L. minor females retain their prothoracic glands even as adults, allowing them to molt as adults under certain environmental or physiological conditions. Thus, neoteny of L. minor is reflected in both the external morphology as well as the internal physiology. The possible developmental changes associated with the evolution of neoteny are discussed.
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Affiliation(s)
- Ming-Luen Jeng
- Department of Biology, National Museum of Natural Science, Taichung City 40453, Taiwan.
| | - Yuichiro Suzuki
- Department of Biological Sciences, Wellesley College, MA 02481, USA
| | - Chih-Yuan Chang
- Chongde Elementary School, Xizhi District, New Taipei City 221, Taiwan
| | - Tsan-Rong Chen
- Mercury Kindergarten, Xindian District, New Taipei City 231, Taiwan
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Martín D, Chafino S, Franch-Marro X. How stage identity is established in insects: the role of the Metamorphic Gene Network. CURRENT OPINION IN INSECT SCIENCE 2021; 43:29-38. [PMID: 33075581 DOI: 10.1016/j.cois.2020.10.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 10/07/2020] [Accepted: 10/07/2020] [Indexed: 06/11/2023]
Abstract
Proper formation of adult insects requires the integration of spatial and temporal regulatory axes. Whereas spatial information confers identity to each tissue, organ and appendage, temporal information specifies at which stage of development the animal is. Regardless of the type of post-embryonic development, either hemimetabolous or holometabolous, temporal specificity is achieved through interactions between the temporal identity genes Kr-h1, E93 and Br-C, whose sequential expression is controlled by the two major developmental hormones, 20-hydroxyecdysone and Juvenile hormone. Given the intimate regulatory connection between these three factors to specify life stage identity, we dubbed the regulatory axis that comprises these genes as the Metamorphic Gene Network (MGN). In this review, we survey the molecular mechanisms underlying the control by the MGN of stage identity and progression in hemimetabolous and holometabolous insects.
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Affiliation(s)
- David Martín
- Institute of Evolutionary Biology (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37-49, 08003 Barcelona, Spain.
| | - Silvia Chafino
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Baldiri Reixac, 10, 08028 Barcelona, Spain
| | - Xavier Franch-Marro
- Institute of Evolutionary Biology (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37-49, 08003 Barcelona, Spain.
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26
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Zeng B, Ye Y, Ma J, Song J. Juvenile hormone upregulates sugarbabe for vitellogenesis and egg development in the migratory locust Locusta migratoria. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2021; 106:e21742. [PMID: 32978973 DOI: 10.1002/arch.21742] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 09/04/2020] [Accepted: 09/07/2020] [Indexed: 06/11/2023]
Abstract
Sugarbabe is a C2 H2 zinc-finger transcription factor that is sensitive to sugar and essential for lipid biosynthesis in larvae of Drosophila melanogaster. However, the role of Sugarbabe in adult insect development remains unexplored. Vitellogenesis is a nutrient-dependent process that is promoted by juvenile hormone (JH) in many insect species. Here, we cloned an ortholog gene of D. melanogaster Sugarbabe (DmSug) in the migratory locust Locusta migratoria. The locust Sugarbabe (LmSug) has five C2 H2 zinc-finger motifs similar to DmSug. LmSug was expressed at a low level in adult female locusts raised under poor nutrient conditions. JH treatment increased the expression level of LmSug. Knockdown of the JH receptor gene Met caused a reduction of LmSug expression. Depletion of the LmSug transcript level caused a significant reduction in vitellogenin expression in the fat body, resulting in impaired oocyte development and ovary growth. The results suggest that LmSug is expressed in response to JH, and plays an essential role in female insect reproduction.
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Affiliation(s)
- Baojuan Zeng
- Key Laboratory of Plant Stress Biology, State Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, Kaifeng, China
| | - Yueru Ye
- Key Laboratory of Plant Stress Biology, State Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, Kaifeng, China
| | - Jiajie Ma
- Key Laboratory of Plant Stress Biology, State Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, Kaifeng, China
| | - Jiasheng Song
- Key Laboratory of Plant Stress Biology, State Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, Kaifeng, China
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27
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Singh A, Raj A, Padmanabhan A, Shah P, Agrawal N. Combating silver nanoparticle-mediated toxicity in Drosophila melanogaster with curcumin. J Appl Toxicol 2020; 41:1188-1199. [PMID: 33146454 DOI: 10.1002/jat.4103] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 10/11/2020] [Accepted: 10/22/2020] [Indexed: 12/21/2022]
Abstract
Nanoscale materials display unique physical and chemical properties that enable their assimilation into a variety of industrial and consumer products. Amongst the widely used nanomaterials, silver nanoparticles (AgNPs) have gained tremendous recognition for various applications, owing to their extraordinary plasmonic and bactericidal properties. Despite of the extensive usage of AgNPs in various sectors, its impact on human health remains ambiguous. Several studies have established that higher doses of AgNPs are detrimental to organismal health. In order to attain the best from these versatile nanoparticles, a recent advent of green nanotechnology, that is, employment of metal nanoparticles synthesized using plant extracts, has emerged. Here, using Drosophila as a model system, we tested if adding curcumin, a biologically active polyphenolic compound present in turmeric, having multitudes of therapeutic properties, could mitigate AgNP-mediated biotoxicity. We found that co-administration of AgNPs with curcumin in the fly food could alleviate several harmful effects evoked by AgNPs ingestion in Drosophila model. Addition of curcumin superseded reduction in feeding, pupation, eclosion, pigmentation, and fertility caused by AgNPs ingestion. Interestingly, impairment in ovary development observed in flies reared on AgNPs-supplemented food was also partially restored by co-administration of AgNPs with curcumin. Furthermore, substantial alleviation of reactive oxygen species level and cell death was observed in larval tissues upon co-supplementation of AgNPs with curcumin. We therefore propose that curcumin, when administered with AgNPs, can abrogate the toxic manifestations of AgNPs ingestion and hence can be incorporated in various consumer products encompassing it.
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Affiliation(s)
- Akanksha Singh
- Department of Zoology, University of Delhi, Delhi, India
| | - Akanksha Raj
- Department of Zoology, University of Delhi, Delhi, India
| | - Aishwarya Padmanabhan
- Department of Zoology, University of Delhi, Delhi, India.,Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, UK
| | - Prasanna Shah
- Department of Physics, Acropolis Institute of Technology and Research, Indore, India
| | - Namita Agrawal
- Department of Zoology, University of Delhi, Delhi, India
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Gao L, Li Y, Xie H, Wang Y, Zhao H, Zhang M, Gu W. Effect of ethylparaben on the growth and development of Drosophila melanogaster on preadult. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2020; 80:103495. [PMID: 32949725 DOI: 10.1016/j.etap.2020.103495] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 08/25/2020] [Accepted: 09/11/2020] [Indexed: 06/11/2023]
Abstract
Parabens are esters of p-hydroxybenzoic acid, including methylparaben (MP), ethylparaben (EP), propylparaben (PP), and the like. This substance has estrogenic and antiandrogenic effects, and a putative role in promoting cancer through endocrine disruption. By exposing Drosophila melanogaster to different concentrations of EP (300 mg/L, 700 mg/L, and 1000 mg/L), we investigated the effect of EP on the growth and development of D. melanogaster before emergence. We found that EP prolonged the development cycle of D. melanogaster, and changed the relative expression levels of Met, Gce, EcR, Kr-h1, and Br. In addition, EP reduced the titer of juvenile hormone Ⅲ (JH Ⅲ) and 20-hydroxyecdysone (20E), and delayed the peak of hormone secretion. This study provided a more objective and thorough assessment of safety for the parabens.
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Affiliation(s)
- Lin Gao
- College of Life Sciences, Shaanxi Normal University, No. 620, West Chang'an Avenue, Chang'an District, Xi'an, 710119, China
| | - Yajuan Li
- College of Life Sciences, Shaanxi Normal University, No. 620, West Chang'an Avenue, Chang'an District, Xi'an, 710119, China
| | - Hongqin Xie
- College of Life Sciences, Shaanxi Normal University, No. 620, West Chang'an Avenue, Chang'an District, Xi'an, 710119, China
| | - Yuan Wang
- College of Life Sciences, Shaanxi Normal University, No. 620, West Chang'an Avenue, Chang'an District, Xi'an, 710119, China
| | - Haizhen Zhao
- College of Life Sciences, Shaanxi Normal University, No. 620, West Chang'an Avenue, Chang'an District, Xi'an, 710119, China
| | - Min Zhang
- College of Life Sciences, Shaanxi Normal University, No. 620, West Chang'an Avenue, Chang'an District, Xi'an, 710119, China
| | - Wei Gu
- College of Life Sciences, Shaanxi Normal University, No. 620, West Chang'an Avenue, Chang'an District, Xi'an, 710119, China.
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Texada MJ, Koyama T, Rewitz K. Regulation of Body Size and Growth Control. Genetics 2020; 216:269-313. [PMID: 33023929 PMCID: PMC7536854 DOI: 10.1534/genetics.120.303095] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 06/29/2020] [Indexed: 12/20/2022] Open
Abstract
The control of body and organ growth is essential for the development of adults with proper size and proportions, which is important for survival and reproduction. In animals, adult body size is determined by the rate and duration of juvenile growth, which are influenced by the environment. In nutrient-scarce environments in which more time is needed for growth, the juvenile growth period can be extended by delaying maturation, whereas juvenile development is rapidly completed in nutrient-rich conditions. This flexibility requires the integration of environmental cues with developmental signals that govern internal checkpoints to ensure that maturation does not begin until sufficient tissue growth has occurred to reach a proper adult size. The Target of Rapamycin (TOR) pathway is the primary cell-autonomous nutrient sensor, while circulating hormones such as steroids and insulin-like growth factors are the main systemic regulators of growth and maturation in animals. We discuss recent findings in Drosophila melanogaster showing that cell-autonomous environment and growth-sensing mechanisms, involving TOR and other growth-regulatory pathways, that converge on insulin and steroid relay centers are responsible for adjusting systemic growth, and development, in response to external and internal conditions. In addition to this, proper organ growth is also monitored and coordinated with whole-body growth and the timing of maturation through modulation of steroid signaling. This coordination involves interorgan communication mediated by Drosophila insulin-like peptide 8 in response to tissue growth status. Together, these multiple nutritional and developmental cues feed into neuroendocrine hubs controlling insulin and steroid signaling, serving as checkpoints at which developmental progression toward maturation can be delayed. This review focuses on these mechanisms by which external and internal conditions can modulate developmental growth and ensure proper adult body size, and highlights the conserved architecture of this system, which has made Drosophila a prime model for understanding the coordination of growth and maturation in animals.
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Affiliation(s)
| | - Takashi Koyama
- Department of Biology, University of Copenhagen, 2100, Denmark
| | - Kim Rewitz
- Department of Biology, University of Copenhagen, 2100, Denmark
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30
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Jaegers J, Gismondi E. Gammarid exposure to pyriproxyfen and/or cadmium: what effects on the methylfarnesoate signalling pathway? ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:31330-31338. [PMID: 32488711 DOI: 10.1007/s11356-020-09419-3] [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: 02/21/2020] [Accepted: 05/21/2020] [Indexed: 06/11/2023]
Abstract
Due to expected changes in climate, it is predicted that disease-carrying mosquitoes will expand their geographical range, resulting in increased use of insect growth regulators (IGRs) to face their proliferation. Among IGRs, pyriproxyfen (PXF) is widely used and has been shown to prevent larvae from developing into adults, rendering them unable to reproduce. However, because of the similarity of crustacean and insect endocrine systems, PXF could also impact aquatic crustaceans. In addition, when spreading in the environment, PXF is found in a mixture with other pollutants such as metallic trace elements, which could alter its effect. Consequently, the present work was devoted to analysing the effects of PXF on the methylfarnesoate (MF) hormonal pathway of the freshwater amphipod Gammarus pulex, as well as its combined binary effects with cadmium (Cd), by measuring MF concentration, as well as the relative transcriptional expression of the farnesoic acid O-methyltransferase (FAMeT) (enzyme limiting the MF production), the methoprene-tolerant receptor (Met), and the broad-complex (BrC) as a transcription factor. Results revealed that single exposures to PXF or Cd have mainly overexpressed FAMeT, Met, and BrC but did not significantly affect MF concentration. Conversely, the mixture exposures seemed to suppress these effects and even achieve antagonistic effects. This work confirmed that PXF single exposure could impact non-target organisms such as amphipods through changes in hormonal pathways of MF. In the same way, it highlighted that Cd could also impair the endocrine system of exposed organisms. However, antagonistic effects have been observed in exposure to mixtures, suggesting different long-term consequences on the growth of amphipods under realistic exposure conditions.
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Affiliation(s)
- Jeremy Jaegers
- Laboratory of Animal Ecology and Ecotoxicology (LEAE) - Freshwater and OceaniC sciences Unit of reSearch (FOCUS), Chemistry Institute, University of Liège, Bât. B6C, 11 allée du 6 Août, B-4000, Sart-Tilman, Belgium.
| | - Eric Gismondi
- Laboratory of Animal Ecology and Ecotoxicology (LEAE) - Freshwater and OceaniC sciences Unit of reSearch (FOCUS), Chemistry Institute, University of Liège, Bât. B6C, 11 allée du 6 Août, B-4000, Sart-Tilman, Belgium
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31
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Chafino S, Ureña E, Casanova J, Casacuberta E, Franch-Marro X, Martín D. Upregulation of E93 Gene Expression Acts as the Trigger for Metamorphosis Independently of the Threshold Size in the Beetle Tribolium castaneum. Cell Rep 2020; 27:1039-1049.e2. [PMID: 31018122 DOI: 10.1016/j.celrep.2019.03.094] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 02/25/2019] [Accepted: 03/25/2019] [Indexed: 11/19/2022] Open
Abstract
Body size in holometabolous insects is determined by the size at which the juvenile larva undergoes metamorphosis to the pupal stage. To undergo larva-pupa transition, larva must reach a critical developmental checkpoint, the threshold size (TS); however, the molecular mechanisms through which the TS cues this transition remain to be fully characterized. Here, we use the flour beetle Tribolium castaneum to characterize the molecular mechanisms underlying entry into metamorphosis. We found that T. castaneum reaches a TS at the beginning of the last larval instar, which is associated with the downregulation of TcKr-h1 and the upregulation of TcE93 and TcBr-C. Unexpectedly, we found that while there is an association between TS and TcE93 upregulation, it is the latter that constitutes the molecular trigger for metamorphosis initiation. In light of our results, we evaluate the interactions that control the larva-pupa transition and suggest alternative models.
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Affiliation(s)
- Silvia Chafino
- Institute of Evolutionary Biology (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37-49, 08003 Barcelona, Spain
| | - Enric Ureña
- Institute of Evolutionary Biology (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37-49, 08003 Barcelona, Spain
| | - Jordi Casanova
- Institut de Biologia Molecular de Barcelona (CSIC), Baldiri Reixac, 4, 08028 Barcelona, Spain; Institut de Recerca Biomèdica de Barcelona, (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Baldiri Reixac, 10, 08028 Barcelona, Spain
| | - Elena Casacuberta
- Institute of Evolutionary Biology (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37-49, 08003 Barcelona, Spain
| | - Xavier Franch-Marro
- Institute of Evolutionary Biology (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37-49, 08003 Barcelona, Spain.
| | - David Martín
- Institute of Evolutionary Biology (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37-49, 08003 Barcelona, Spain.
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Mao Y, Li Y, Gao H, Lin X. Krüppel homologue 1 interacts directly with Hairy and regulates ecdysis in the brown planthopper. INSECT MOLECULAR BIOLOGY 2020; 29:293-300. [PMID: 31908059 DOI: 10.1111/imb.12635] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 11/27/2019] [Accepted: 12/27/2019] [Indexed: 06/10/2023]
Abstract
Juvenile hormone (JH) plays important roles in the growth and development of insects. JH and its receptor methoprene-tolerant (Met) regulate the expression of transcription factors to control the transcription of downstream genes. The expression of Hairy (Hry) and Krüppel homologue 1 (Kr-h1) is regulated by JH and JH receptors. Hry and Kr-h1 are both crucial in mediating JH signalling. However, whether they interact at the gene level in regulating metamorphosis and whether they interact physically at the protein level remain unknown. We used co-immunoprecipitation, glutathione S-transferase pull-down and RNA interference (RNAi) approaches to study the genetic and biochemical interactions of the two proteins Hry and Kr-h1. The results showed that brown planthopper (Nilaparvata lugens) Hry and Kr-h1 interact directly: Hry binds to the N-terminal of Kr-h1, which includes five zinc-finger domains. The RNAi experiment showed that downregulation of Hry reduced the ratio of ecdysis failure caused by knockdown of Kr-h1, indicating that the downregulation of Hry might mitigate ecdysis failure via the downregulation of Kr-h1. The expression of Hry increased significantly when Kr-h1 was downregulated, whereas it did not change significantly when both were downregulated. Our results suggest that the binding of Hry protein with Kr-h1 prevents the N-terminal five zinc-finger domains from binding with DNA, which in turn inactivates the transcription activator or inhibitor function of Kr-h1. Hry could possibly be used as a target for pesticide applications in the future.
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Affiliation(s)
- Y Mao
- Key Laboratory of Marine Food Quality and Hazard Controlling Technology of Zhejiang Province, College of Life Sciences, China Jiliang University, Hangzhou, China
| | - Y Li
- Key Laboratory of Marine Food Quality and Hazard Controlling Technology of Zhejiang Province, College of Life Sciences, China Jiliang University, Hangzhou, China
| | - H Gao
- Key Laboratory of Marine Food Quality and Hazard Controlling Technology of Zhejiang Province, College of Life Sciences, China Jiliang University, Hangzhou, China
| | - X Lin
- Key Laboratory of Marine Food Quality and Hazard Controlling Technology of Zhejiang Province, College of Life Sciences, China Jiliang University, Hangzhou, China
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Ding N, Wang Z, Geng N, Zou H, Zhang G, Cao C, Li X, Zou C. Silencing Br-C impairs larval development and chitin synthesis in Lymantria dispar larvae. JOURNAL OF INSECT PHYSIOLOGY 2020; 122:104041. [PMID: 32126216 DOI: 10.1016/j.jinsphys.2020.104041] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 02/28/2020] [Accepted: 02/28/2020] [Indexed: 06/10/2023]
Abstract
In insects, 20-hydroxyecdysone (20E) mediates developmental transitions and regulates molting processes through activation of a series of transcription factors. Broad-Complex (Br-C), a vital gene in the 20E signalling pathway, plays crucial roles during insect growth processes. However, whether Br-C affects chitin synthesis in insects remains unclear. In the present study, the Br-C gene from Lymantria dispar, a notorious defoliator of forestry, was identified based on transcriptome data, and subjected to bioinformatic analysis. The regulatory functions of LdBr-C in chitin synthesis and metabolism in L. dispar larvae were analysed by RNA interference (RNAi). The full-length LdBr-C gene (1431 bp) encodes a 477 amino acid (aa) polypeptide containing a common BRcore region (391 aa) at the N-terminus and a C-terminal Zinc finger domain (56 aa) harbouring two characteristic C2H2 motifs (CXXC and HXXXXH). Phylogenetic analyses showed that LdBr-C shares highest homology and identity with Br-C isoform 7 (83.12%) of Helicoverpa armigera. Expression profiles indicate that LdBr-C was expressed throughout larval and pupal stages, and highly expressed in prepupal and pupal stages. Furthermore, LdBr-C expression was strongly induced by exogenous 20E, and suppressed dramatically after application of dsLdBr-C. Bioassay results showed that knockdown of LdBr-C caused larval developmental deformity, significant weight loss, and a mortality rate of 67.18%. Knockdown of LdBr-C significantly down-regulated transcription levels of eight critical genes (LdTre1, LdTre2, LdG6PI, LdUAP, LdCHS1, LdCHS2, LdTPS and LdCHT) related to chitin synthesis and metabolism, thereby lowering the chitin content in the midgut and epidermis. Our findings demonstrate that Br-C knockdown impairs larval development and chitin synthesis in L. dispar.
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Affiliation(s)
- Nan Ding
- School of Forestry, Northeast Forestry University, Harbin 150040, PR China
| | - Zhiying Wang
- School of Forestry, Northeast Forestry University, Harbin 150040, PR China
| | - Nannan Geng
- School of Forestry, Northeast Forestry University, Harbin 150040, PR China
| | - Hang Zou
- School of Forestry, Northeast Forestry University, Harbin 150040, PR China
| | - Guocai Zhang
- School of Forestry, Northeast Forestry University, Harbin 150040, PR China
| | - Chuanwang Cao
- School of Forestry, Northeast Forestry University, Harbin 150040, PR China
| | - Xingpeng Li
- Jilin Province Academy of Forestry Sciences, PR China
| | - Chuanshan Zou
- School of Forestry, Northeast Forestry University, Harbin 150040, PR China.
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Naruse S, Washidu Y, Miura K, Shinoda T, Minakuchi C. Methoprene-tolerant is essential for embryonic development of the red flour beetle Tribolium castaneum. JOURNAL OF INSECT PHYSIOLOGY 2020; 121:104017. [PMID: 31972216 DOI: 10.1016/j.jinsphys.2020.104017] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 12/27/2019] [Accepted: 01/13/2020] [Indexed: 06/10/2023]
Abstract
Insect juvenile hormone (JH) is well known to regulate post-embryonic development and reproduction in concert with ecdysteroids in a variety of insect species. In contrast, our knowledge on the role of JH in embryonic development is limited and inconsistent. Preceding studies indicate that JH biosynthesis or JH signaling genes are dispensable in holometabolous Drosophila melanogaster and Bombyx mori, while essential in hemimetabolous Blattella germanica. In the red flour beetle Tribolium castaneum, we performed functional analyses of key factors in JH signaling, i.e. the JH receptor Methoprene-tolerant (Met) and the early JH-response gene Krüppel homolog 1 (Kr-h1) using parental RNA interference. Knockdown of Met resulted in a significant reduction in hatching rates and survival rates in the first and second larval instars. Meanwhile, knockdown of Kr-h1 caused no significant effect on hatching or survival. The unhatched embryos under Met knockdown developed up to the late embryonic stage, but their body shape was flat and tubby compared with the controls. Attempts to suppress JH biosynthesis by parental RNA interference of JH biosynthetic enzymes were unsuccessful due to insufficient knockdown efficiency. These results suggested that Met but not Kr-h1 is essential for the embryonic development of T. castaneum, although involvement of JH still remains to be examined. Taken together, the function of Met in embryonic development seems to be diverse among insect species.
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Affiliation(s)
- Shouya Naruse
- Applied Entomology Laboratory, Graduate School of Bio-Agricultural Sciences, Nagoya University, Furocho, Chikusa, Nagoya 464-8601, Japan
| | - Yumiko Washidu
- Applied Entomology Laboratory, Graduate School of Bio-Agricultural Sciences, Nagoya University, Furocho, Chikusa, Nagoya 464-8601, Japan
| | - Ken Miura
- Applied Entomology Laboratory, Graduate School of Bio-Agricultural Sciences, Nagoya University, Furocho, Chikusa, Nagoya 464-8601, Japan
| | - Tetsuro Shinoda
- National Agriculture and Food Research Organization, 1-2 Ohwashi, Tsukuba 305-8634, Japan; Faculty of Food and Agricultural Sciences, Fukushima University, 1 Kanayagawa, Fukushima 960-1296, Japan
| | - Chieka Minakuchi
- Applied Entomology Laboratory, Graduate School of Bio-Agricultural Sciences, Nagoya University, Furocho, Chikusa, Nagoya 464-8601, Japan; National Agriculture and Food Research Organization, 1-2 Ohwashi, Tsukuba 305-8634, Japan.
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Abstract
This autobiographical article describes the research career of Lynn M. Riddiford from its early beginnings in a summer program for high school students at Jackson Laboratory to the present "retirement" at the Friday Harbor Laboratories. The emphasis is on her forays into many areas of insect endocrinology, supported by her graduate students and postdoctoral associates. The main theme is the hormonal regulation of metamorphosis, especially the roles of juvenile hormone (JH). The article describes the work of her laboratory first in the elucidation of the endocrinology of the tobacco hornworm, Manduca sexta, and later in the molecular aspects of the regulation of cuticular and pigment proteins and of the ecdysone-induced transcription factor cascade during molting and metamorphosis. Later studies utilized Drosophila melanogaster to answer further questions about the actions of JH.
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Affiliation(s)
- Lynn M Riddiford
- Friday Harbor Laboratories, University of Washington, Friday Harbor, Washington 98250, USA;
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Nijhout HF, McKenna KZ. Allometry, Scaling, and Ontogeny of Form-An Introduction to the Symposium. Integr Comp Biol 2019; 59:1275-1280. [PMID: 31553435 DOI: 10.1093/icb/icz143] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Until recently, the study of allometry has been mostly descriptive, and consisted of a diversity of methods for fitting regressions to bivariate or multivariate morphometric data. During the past decade, researchers have been developing methods to extract biological information from allometric data that could be used to deduce the underlying mechanisms that gave rise to the allometry. In addition, an increasing effort has gone into understanding the kinetics of growth and the regulatory mechanisms that control growth of the body and its component parts. The study of allometry and scaling has now become an exceptionally diverse field, with different investigators applying state of the art methods and concepts in evolution, developmental biology, cell biology, and genetics. Diversity has caused divergence, and we felt that although there is general agreement about the new goals for the study of allometry (understanding underlying mechanisms and how those evolve to produce different morphologies), progress is hindered by lack of coordination among the different approaches. We felt the time was right to bring these diverse practitioners together in a symposium to discuss their most recent work in the hope of forging new functional, conceptual, and collaborative connections among established and novice practitioners.
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Lavine MD, Gotoh H, Hayes A, Corley Lavine L. The Insulin Signaling Substrate Chico and the Ecdysone Response Element Broad Both Regulate Growth of the Head Horns in the Asian Rhinoceros Beetle, Trypoxylus dichotomus. Integr Comp Biol 2019; 59:1338-1345. [PMID: 31165143 DOI: 10.1093/icb/icz093] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Males of the Asian rhinoceros beetle, Trypoxylus dichotomus, possess exaggerated head and thoracic horns that scale dramatically out of proportion to body size. While RNAi-mediated knockdowns of the insulin receptor suggest that the insulin signaling pathway regulates nutrition-dependent growth including exaggerated horns, the genes that regulate disproportionate growth have yet to be identified. We used RNAi-mediated knockdown of several genes to investigate their potential role in growth and scaling of the sexually dimorphic, exaggerated head horns of T. dichotomus. Knockdown of the insulin signaling substrate chico and the ecdysone response element broad caused significant decreases in head horn length, while having no or minimal effects on other structures such as elytra and tibiae. However, scaling of horns to body size was not affected by either knockdown. In addition, knockdown of phosphatase and tensin homolog, a negative regulator of the insulin signaling pathway, had no significant effects on any trait. Our results do not identify any candidate genes that may specifically mediate the allometric aspect of horn growth, but they do confirm the insulin signaling pathway as a mediator of conditional trait expression, and importantly implicate the ecdysone signaling pathway, possibly in conjunction with insulin signaling, as an additional mediator of horn growth.
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Affiliation(s)
- Mark D Lavine
- Department of Entomology, Washington State University, Pullman, WA 99164, USA
| | - Hiroki Gotoh
- Faculty of Environmental Earth Sciences, Hokkaido University, Sapporo, Hokkaido 0600810, Japan
| | - Abigail Hayes
- Department of Entomology, Washington State University, Pullman, WA 99164, USA
| | - Laura Corley Lavine
- Department of Entomology, Washington State University, Pullman, WA 99164, USA
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Xu QY, Meng QW, Deng P, Fu KY, Guo WC, Li GQ. Impairment of pupation by RNA interference-aided knockdown of Broad- Complex gene in Leptinotarsa decemlineata (Say). BULLETIN OF ENTOMOLOGICAL RESEARCH 2019; 109:659-668. [PMID: 30704539 DOI: 10.1017/s0007485318001050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Dietary delivery of bacterially expressed double-stranded RNA (dsRNA) has a great potential for management of Leptinotarsa decemlineata. An important first step is to discover possible RNA-interference (RNAi)-target genes effective against larvae, especially the old larvae. In the present paper, five putative Broad-Complex (BrC) cDNAs (Z1-Z4, and Z6) were identified in L. decemlineata. The expression of the five LdBrC isoforms was suppressed by juvenile hormone signaling, whereas the transcription was upregulated by 20-hydroxyecdysone signaling at the fourth (final) instar larval stage. Feeding of bacterially expressed dsBrC (derived from a common fragment of the five LdBrC variants) in the third- and fourth-instar larvae successfully knocked down the target mRNAs. For the fourth-instar LdBrC RNAi hypomorphs, they had a higher larval mortality compared with the controls. Moreover, most dsBrC-fed beetles did not pupate normally. After removal of the apolysed larval cuticle, a miniature adult was found. The adult head, compound eyes, prothorax, mesothorax, metathorax were found on the dorsal view. Distinct adult cuticle pigmentation was seen on the prothorax. The mouthparts, forelegs, midlegs, and hindlegs could be observed on the ventral view of the miniature adults. For the third-instar LdBrC RNAi specimens, around 20% moribund beetles remained as prepupae and finally died. Therefore, LdBrC is among the most attractive candidate genes for RNAi to control the fourth-instar larvae in L. decemlineata.
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Affiliation(s)
- Q-Y Xu
- Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Q-W Meng
- Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - P Deng
- Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - K-Y Fu
- Department of Plant Protection, Xinjiang Academy of Agricultural Sciences, Urumqi 830091, China
| | - W-C Guo
- Department of Plant Protection, Xinjiang Academy of Agricultural Sciences, Urumqi 830091, China
| | - G-Q Li
- Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
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Fujimori H, Zhou YJ, Fukumura K, Matsumoto S, Tukamoto Y, Nagata S. Specific distribution of expression and enzymatic activity of cholesterol biosynthetic enzyme DHCR24 orthologs in the phytophagous insect. Biosci Biotechnol Biochem 2019; 84:126-133. [PMID: 31538545 DOI: 10.1080/09168451.2019.1667221] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Insects must intake sterol compounds because of their inability to synthesize cholesterol de novo. In phytophagous insects, enzymatic conversion of phytosterols to cholesterol involving 24-dehydrocholesterol reductase (DHCR24) exerts to acquire cholesterol. Here, we reported the presence of two DHCR24 homologs in the silkworm Bombyx mori, BmDHCR24-1 and -2, with several transcript variants. Consistent with the data of spatial expression analyses by RT-PCR, predominant enzymatic activity of DHCR24 was observed in B. mori larval midgut whereas weak activity was observed in the other tissues examined. In addition, BmDHCR24-1 expression in HEK293 cells showed an enzymatic activity, but BmDHCR24-2 did not, although both BmDHCR24s were localized in the endoplasmic reticulum, where the mammalian DHCR24s are located to exert their enzymatic activities. The present data indicated that BmDHCR24-1 but not BmDHCR24-2 contributes to conversion of phytosterols to cholesterol mainly in the midgut of the phytophagous lepidopteran larvae.
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Affiliation(s)
- Haruna Fujimori
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, the University of Tokyo, Kashiwa City, Chiba, Japan
| | - Yi Jun Zhou
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, the University of Tokyo, Kashiwa City, Chiba, Japan.,Research Fellow of Japan Society for the Promotion of Science (JSPS), Chiyoda-ku, Tokyo, Japan
| | - Keisuke Fukumura
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, the University of Tokyo, Kashiwa City, Chiba, Japan.,Research Fellow of Japan Society for the Promotion of Science (JSPS), Chiyoda-ku, Tokyo, Japan
| | - Sumihiro Matsumoto
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, the University of Tokyo, Kashiwa City, Chiba, Japan
| | - Yusuke Tukamoto
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, the University of Tokyo, Kashiwa City, Chiba, Japan.,Research Fellow of Japan Society for the Promotion of Science (JSPS), Chiyoda-ku, Tokyo, Japan
| | - Shinji Nagata
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, the University of Tokyo, Kashiwa City, Chiba, Japan
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Belles X. The innovation of the final moult and the origin of insect metamorphosis. Philos Trans R Soc Lond B Biol Sci 2019; 374:20180415. [PMID: 31438822 DOI: 10.1098/rstb.2018.0415] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The three modes of insect postembryonic development are ametaboly, hemimetaboly and holometaboly, the latter being considered the only significant metamorphosis mode. However, the emergence of hemimetaboly, with the genuine innovation of the final moult, represents the origin of insect metamorphosis and a necessary step in the evolution of holometaboly. Hemimetaboly derives from ametaboly and might have appeared as a consequence of wing emergence in Pterygota, in the early Devonian. In extant insects, the final moult is mainly achieved through the degeneration of the prothoracic gland (PG), after the formation of the winged and reproductively competent adult stage. Metamorphosis, including the formation of the mature wings and the degeneration of the PG, is regulated by the MEKRE93 pathway, through which juvenile hormone precludes the adult morphogenesis by repressing the expression of transcription factor E93, which triggers this change. The MEKRE93 pathway appears conserved in extant metamorphosing insects, which suggest that this pathway was operative in the Pterygota last common ancestor. We propose that the final moult, and the consequent hemimetabolan metamorphosis, is a monophyletic innovation and that the role of E93 as a promoter of wing formation and the degeneration of the PG was mechanistically crucial for their emergence. This article is part of the theme issue 'The evolution of complete metamorphosis'.
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Affiliation(s)
- Xavier Belles
- Institute of Evolutionary Biology (CSIC-Universitat Pompeu Fabra), Passeig Maritim 37, 08003 Barcelona, Spain
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41
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Ishimaru Y, Tomonari S, Watanabe T, Noji S, Mito T. Regulatory mechanisms underlying the specification of the pupal-homologous stage in a hemimetabolous insect. Philos Trans R Soc Lond B Biol Sci 2019; 374:20190225. [PMID: 31438810 DOI: 10.1098/rstb.2019.0225] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Juvenile hormones and the genetic interaction between the transcription factors Krüppel homologue 1 (Kr-h1) and Broad (Br) regulate the transformation of insects from immature to adult forms in both types of metamorphosis (holometaboly with a pupal stage versus hemimetaboly with no pupal stage); however, knowledge about the exact instar in which this occurs is limited. Using the hemimetabolous cricket Gryllus bimaculatus (Gb), we demonstrate that a genetic interaction occurs among Gb'Kr-h1, Gb'Br and the adult-specifier transcription factor Gb'E93 from the sixth to final (eighth) nymphal instar. Gb'Kr-h1 and Gb'Br mRNAs were strongly expressed in the abdominal tissues of sixth instar nymphs, with precocious adult moults being induced by Gb'Kr-h1 or Gb'Br knockdown in the sixth instar. The depletion of Gb'Kr-h1 or Gb'Br upregulates Gb'E93 in the sixth instar. By contrast, Gb'E93 knockdown at the sixth instar prevents nymphs transitioning to adults, instead producing supernumerary nymphs. Gb'E93 also represses Gb'Kr-h1 and Gb'Br expression in the penultimate nymphal instar, demonstrating its important role in adult differentiation. Our results suggest that the regulatory mechanisms underlying the pupal transition in holometabolous insects are evolutionarily conserved in hemimetabolous G. bimaculatus, with the penultimate and final nymphal periods being equivalent to the pupal stage. This article is part of the theme issue 'The evolution of complete metamorphosis'.
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Affiliation(s)
- Yoshiyasu Ishimaru
- Division of Bioscience and Bioindustry, Graduate School of Technology, Industrial and Social Sciences, Tokushima University, 2-1 Minami-Jyosanjima-cho, Tokushima City, Tokushima 770-8513, Japan
| | - Sayuri Tomonari
- Division of Chemical and Physical Analyses, Center for Technical Support, Institute of Technology and Science, Tokushima University, 2-1 Minami-Jyosanjima-cho, Tokushima City, Tokushima 770-8506, Japan
| | - Takahito Watanabe
- Division of Bioscience and Bioindustry, Graduate School of Technology, Industrial and Social Sciences, Tokushima University, 2-1 Minami-Jyosanjima-cho, Tokushima City, Tokushima 770-8513, Japan
| | - Sumihare Noji
- Division of Bioscience and Bioindustry, Graduate School of Technology, Industrial and Social Sciences, Tokushima University, 2-1 Minami-Jyosanjima-cho, Tokushima City, Tokushima 770-8513, Japan
| | - Taro Mito
- Division of Bioscience and Bioindustry, Graduate School of Technology, Industrial and Social Sciences, Tokushima University, 2-1 Minami-Jyosanjima-cho, Tokushima City, Tokushima 770-8513, Japan
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Jindra M. Where did the pupa come from? The timing of juvenile hormone signalling supports homology between stages of hemimetabolous and holometabolous insects. Philos Trans R Soc Lond B Biol Sci 2019; 374:20190064. [PMID: 31438814 DOI: 10.1098/rstb.2019.0064] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Insect metamorphosis boasts spectacular cases of postembryonic development when juveniles undergo massive morphogenesis before attaining the adult form and function; in moths or flies the larvae do not even remotely resemble their adult parents. A selective advantage of complete metamorphosis (holometaboly) is that within one species the two forms with different lifestyles can exploit diverse habitats. It was the environmental adaptation and specialization of larvae, primarily the delay and internalization of wing development, that eventually required an intermediate stage that we call a pupa. It is a long-held and parsimonious hypothesis that the holometabolous pupa evolved through modification of a final juvenile stage of an ancestor developing through incomplete metamorphosis (hemimetaboly). Alternative hypotheses see the pupa as an equivalent of all hemimetabolous moulting cycles (instars) collapsed into one, and consider any preceding holometabolous larval instars free-living embryos stalled in development. Discoveries on juvenile hormone signalling that controls metamorphosis grant new support to the former hypothesis deriving the pupa from a final pre-adult stage. The timing of expression of genes that repress and promote adult development downstream of hormonal signals supports homology between postembryonic stages of hemimetabolous and holometabolous insects. This article is part of the theme issue 'The evolution of complete metamorphosis'.
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Affiliation(s)
- Marek Jindra
- Biology Centre of the Czech Academy of Sciences, Institute of Entomology, Ceske Budejovice 370 05, Czech Republic
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43
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Truman JW, Riddiford LM. The evolution of insect metamorphosis: a developmental and endocrine view. Philos Trans R Soc Lond B Biol Sci 2019; 374:20190070. [PMID: 31438820 PMCID: PMC6711285 DOI: 10.1098/rstb.2019.0070] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Developmental, genetic and endocrine data from diverse taxa provide insight into the evolution of insect metamorphosis. We equate the larva–pupa–adult of the Holometabola to the pronymph–nymph–adult of hemimetabolous insects. The hemimetabolous pronymph is a cryptic embryonic stage with unique endocrinology and behavioural modifications that probably served as preadaptations for the larva. It develops in the absence of juvenile hormone (JH) as embryonic primordia undergo patterning and morphogenesis, the processes that were arrested for the evolution of the larva. Embryonic JH then drives tissue differentiation and nymph formation. Experimental treatment of pronymphs with JH terminates patterning and induces differentiation, mimicking the processes that occurred during the evolution of the larva. Unpatterned portions of primordia persist in the larva, becoming imaginal discs that form pupal and adult structures. Key transcription factors are associated with the holometabolous life stages: Krüppel-homolog 1 (Kr-h1) in the larva, broad in the pupa and E93 in the adult. Kr-h1 mediates JH action and is found whenever JH acts, while the other two genes direct the formation of their corresponding stages. In hemimetabolous forms, the pronymph has low Broad expression, followed by Broad expression through the nymphal moults, then a switch to E93 to form the adult. This article is part of the theme issue ‘The evolution of complete metamorphosis’.
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Affiliation(s)
- James W Truman
- Department of Biology, Friday Harbor Laboratories, University of Washington, Friday Harbor, WA 98250, USA
| | - Lynn M Riddiford
- Department of Biology, Friday Harbor Laboratories, University of Washington, Friday Harbor, WA 98250, USA
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Huang J, Fang L, Wang S, Liu X, Chen Y, Chen Y, Tian H, Lin S, Tian S, Wei H, Gu X. Molecular cloning, expression profiling, and functional analysis of a broad-complex isoform 2/3 (Br-Z2/Z3) transcription factor in the diamondback moth, Plutella xylostella (L.). ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2019; 101:e21549. [PMID: 30941822 DOI: 10.1002/arch.21549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 02/23/2019] [Accepted: 03/06/2019] [Indexed: 06/09/2023]
Abstract
The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is a widespread and destructive pest of cruciferous crops. New strategies for controlling it are needed because it is rapidly developing resistance to conventional pesticides. In insects, transcription factors (TFs) including broad-complex (Br-C) are thought to be useful for insecticide development because they are able to regulate the transcription of functional genes involved in responses to external stimuli including insecticides. In the present study, we cloned and sequenced the open reading frames (ORFs) of three BTB-ZF encoding genes from the diamondback moth deposited in the National Center for Biotechnology Information (NCBI) database under accessions MG753773, MG288674, and MG753772. The lengths of these ORFs were 1,680, 1,428, and 1,647 bp, respectively. The phylogenetic analysis based on the predicted amino acid sequences of ZF domains showed that MG753773 and MG288674 belonged to Z2/Z3 and Z7 of Br-C while MG753772 belonged to Ttk types. In the agreement, the highest expression level of MG753773 occurred during the prepupal stage, MG288674 and MG753772 were expressed during all stages and peaked in the adult and egg stages, respectively. RNA interference silencing of MG753773 in the late third instar larvae significantly decreased survival and pupation of the insects. With precocene II, transcription of MG753773 increased (4×) in the fourth instar larva 24 hr later; 48 hr later the rate of prepupation and pupation was significantly higher. These findings will contribute to the development of new regulators of the growth and development for diamondback moth control.
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Affiliation(s)
- Jingfei Huang
- College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, Fujian Province, China
| | - Ling Fang
- College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, Fujian Province, China
| | - Shuai Wang
- College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, Fujian Province, China
| | - Xiang Liu
- College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, Fujian Province, China
| | - Yong Chen
- Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian Province, China
- Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian Province, China
| | - Yixin Chen
- Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian Province, China
- Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian Province, China
| | - Houjun Tian
- Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian Province, China
- Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian Province, China
| | - Shuo Lin
- Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian Province, China
- Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian Province, China
| | - Sufen Tian
- College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, Fujian Province, China
| | - Hui Wei
- Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian Province, China
- Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian Province, China
| | - Xiaojun Gu
- College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, Fujian Province, China
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45
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Liu X, Zhang S, Shen ZJ, Liu Y, Li Z, Liu X. Vrille is required for larval moulting and metamorphosis of Helicoverpa armigera (Lepidoptera: Noctuidae). INSECT MOLECULAR BIOLOGY 2019; 28:355-371. [PMID: 30485565 DOI: 10.1111/imb.12557] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Vrille (Vri), a basic leucine zipper transcription factor, plays important roles in insect circadian clock regulation, tracheal development, proliferation, flight and metamorphosis. Here, Helicoverpa armigera was used as a model to investigate the role of Vri in larval moulting and metamorphosis. Sequence analysis results revealed that H. armigera Vri (HaVri) shares a high amino acid identity with other Lepidoptera Vri homologues. Spatial-temporal expression pattern data showed that HaVri expression was highly abundant in larval moulting and metamorphosis stages and was mainly expressed in the midgut and Malpighian tubule during metamorphosis. HaVri knockdown by RNA interference in the fourth-instar larvae prevented larval moulting, and HaVri knockdown in the fifth-instar larvae suppressed midgut remodelling and delayed or blocked metamorphosis. Further studies confirmed that 20-hydroxyecdysone (20E) activated HaVri expression via its heterodimer receptors, ecdysone receptor (EcRB1) and ultraspiracle protein (USP1), whereas methoprene [juvenile hormone analogue (JHA)] promoted HaVri expression via its intracellular receptor methoprene-tolerant (Met1). However, 20E and JHA can counteract each other in the activation of HaVri expression. Together, the present results suggested that HaVri was involved in larval moulting and metamorphosis and was regulated by 20E and JHA in H. armigera.
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Affiliation(s)
- X Liu
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, 100193, Beijing, China
| | - S Zhang
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, 100193, Beijing, China
| | - Z J Shen
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, 100193, Beijing, China
| | - Y Liu
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, 100193, Beijing, China
| | - Z Li
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, 100193, Beijing, China
| | - X Liu
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, 100193, Beijing, China
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46
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Xu QY, Meng QW, Deng P, Fu KY, Guo WC, Li GQ. Isoform specific roles of Broad-Complex in larval development in Leptinotarsa decemlineata. INSECT MOLECULAR BIOLOGY 2019; 28:420-430. [PMID: 30632239 DOI: 10.1111/imb.12563] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Broad-Complex (BrC) is a downstream target of both 20-hydroxyecdysone and juvenile hormone signalling. BrC regulates morphogenetic changes between nymphal instars in hemimetabolans, whereas it controls pupal commitment, pupal morphogenesis and inhibits adult differentiation in holometabolans. Among five BrC cDNAs (Z1-Z4 and Z6) identified in the Colorado potato beetle, we found in this work that Z1, Z2 and Z6 were mainly expressed at the last (fourth) instar and prepupal stages, whereas the levels of Z3 and Z4 increased during the penultimate (third) instar stage, peaked at the last instar larval phase and gradually decreased at the prepupal and pupal periods. When knocking down all BrC isoforms by RNA interference (RNAi) at the penultimate instar stage, around 20% of the resultant larvae remained as moribund beetles. These moribund BrC RNAi larvae were completely or partially wrapped in old cuticle. Likewise, a portion of larvae treated for a single double-stranded RNA of Z3, Z4 or Z6 displayed a degree of similar aberrancies, increasing in the order of isoforms Z6 < Z3 < Z4. When silencing all BrC isoforms at the last instar period, most of the RNAi larvae did not normally pupate or emerge as adults. Separately silencing each of the five zinc finger domains revealed that approximately 70% of the Z1 RNAi larvae remained as prepupae, around 60% of the Z6 RNAi specimens formed aberrant prepupae or pupae and about 60% of the Z2 RNAi beetles became deformed pupae. After removal of the old exuviae, these deformed larvae in which either Z1, Z2 or Z6 was depleted possessed adult prothorax and mesothorax, developing antenna, mouthparts and wing discs. Moreover, less than 50% of the resultant pupae finally emerged as adults when either of Z1, Z2 or Z6 was knocked down. Therefore, our findings reveal, for the first time, that the two roles of BrC in insect groups (ie directing morphogenetic changes during juvenile development and regulating larval-pupal-adult metamorphosis) are played by different BrC isoforms in Leptinotarsa decemlineata.
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Affiliation(s)
- Q-Y Xu
- Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Q-W Meng
- Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - P Deng
- Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - K-Y Fu
- Institute of Microbiological Application, Xinjiang Academy of Agricultural Science, Urumqi, China
| | - W-C Guo
- Institute of Microbiological Application, Xinjiang Academy of Agricultural Science, Urumqi, China
| | - G-Q Li
- Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
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McKenna KZ, Tao D, Nijhout HF. Exploring the Role of Insulin Signaling in Relative Growth: A Case Study on Wing-Body Scaling in Lepidoptera. Integr Comp Biol 2019; 59:1324-1337. [DOI: 10.1093/icb/icz080] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Abstract
Adult forms emerge from the relative growth of the body and its parts. Each appendage and organ has a unique pattern of growth that influences the size and shape it attains. This produces adult size relationships referred to as static allometries, which have received a great amount of attention in evolutionary and developmental biology. However, many questions remain unanswered, for example: What sorts of developmental processes coordinate growth? And how do these processes change given variation in body size? It has become increasingly clear that nutrition is one of the strongest influences on size relationships. In insects, nutrition acts via insulin/TOR signaling to facilitate inter- and intra-specific variation in body size and appendage size. Yet, the mechanism by which insulin signaling influences the scaling of growth remains unclear. Here we will discuss the potential roles of insulin signaling in wing-body scaling in Lepidoptera. We analyzed the growth of wings in animals reared on different diet qualities that induce a range of body sizes not normally present in our laboratory populations. By growing wings in tissue culture, we survey how perturbation and stimulation of insulin/TOR signaling influences wing growth. To conclude, we will discuss the implications of our findings for the development and evolution of organismal form.
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Affiliation(s)
| | - Della Tao
- Department of Biology, Duke University, Durham, NC 27708, USA
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Suzuki Y, Chou J, Garvey SL, Wang VR, Yanes KO. Evolution and Regulation of Limb Regeneration in Arthropods. Results Probl Cell Differ 2019; 68:419-454. [PMID: 31598866 DOI: 10.1007/978-3-030-23459-1_17] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Regeneration has fascinated both scientists and non-scientists for centuries. Many organisms can regenerate, and arthropod limbs are no exception although their ability to regenerate is a product shaped by natural and sexual selection. Recent studies have begun to uncover cellular and molecular processes underlying limb regeneration in several arthropod species. Here we argue that an evo-devo approach to the study of arthropod limb regeneration is needed to understand aspects of limb regeneration that are conserved and divergent. In particular, we argue that limbs of different species are comprised of cells at distinct stages of differentiation at the time of limb loss and therefore provide insights into regeneration involving both stem cell-like cells/precursor cells and differentiated cells. In addition, we review recent studies that demonstrate how limb regeneration impacts the development of the whole organism and argue that studies on the link between local tissue damage and the rest of the body should provide insights into the integrative nature of development. Molecular studies on limb regeneration are only beginning to take off, but comparative studies on the mechanisms of limb regeneration across various taxa should not only yield interesting insights into development but also answer how this remarkable ability evolved across arthropods and beyond.
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Affiliation(s)
- Yuichiro Suzuki
- Department of Biological Sciences, Wellesley College, Wellesley, MA, USA.
| | - Jacquelyn Chou
- Department of Biological Sciences, Wellesley College, Wellesley, MA, USA
| | - Sarah L Garvey
- Department of Biological Sciences, Wellesley College, Wellesley, MA, USA
| | - Victoria R Wang
- Department of Biological Sciences, Wellesley College, Wellesley, MA, USA
| | - Katherine O Yanes
- Department of Biological Sciences, Wellesley College, Wellesley, MA, USA
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Hyde CJ, Elizur A, Ventura T. The crustacean ecdysone cassette: A gatekeeper for molt and metamorphosis. J Steroid Biochem Mol Biol 2019; 185:172-183. [PMID: 30157455 DOI: 10.1016/j.jsbmb.2018.08.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 08/21/2018] [Accepted: 08/25/2018] [Indexed: 10/28/2022]
Abstract
Arthropods have long been utilized as models to explore molecular function, and the findings derived from them can be applied throughout metazoa, including as a basis for medical research. This has led to the adoption of many representative insect models beyond Drosophila, as each lends its own unique perspective to questions in endocrinology and genetics. However, non-insect arthropods are yet to be realised for the potential insight they may provide in such studies. The Crustacea are among the most ancient arthropods from which insects descended, comprising a huge variety of life histories and ecological roles. Of the events in a typical crustacean development, metamorphosis is perhaps the most ubiquitous, challenging and highly studied. Despite this, our knowledge of the endocrinology which underpins metamorphosis is rudimentary at best; although several key molecules have been identified and studied in depth, the link between them is quite nebulous and leans heavily on well-explored insect models, which diverged from the Pancrustacea over 450 million years ago. As omics technologies become increasingly accessible, they bring the prospect of explorative molecular research which will allow us to uncover components and pathways unique to crustaceans. This review reconciles known components of crustacean metamorphosis and reflects on our findings in insects to outline a future search space, with focus given to the ecdysone cascade. To expand our knowledge of this ubiquitous endocrine system not only aids in our understanding of crustacean metamorphosis, but also provides a deeper insight into the adaptive capacity of arthropods throughout evolution.
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Affiliation(s)
- Cameron J Hyde
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 4 Locked Bag, Maroochydore, Queensland, 4558, Australia
| | - Abigail Elizur
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 4 Locked Bag, Maroochydore, Queensland, 4558, Australia
| | - Tomer Ventura
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 4 Locked Bag, Maroochydore, Queensland, 4558, Australia.
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Bittova L, Jedlicka P, Dracinsky M, Kirubakaran P, Vondrasek J, Hanus R, Jindra M. Exquisite ligand stereoselectivity of a Drosophila juvenile hormone receptor contrasts with its broad agonist repertoire. J Biol Chem 2018; 294:410-423. [PMID: 30455350 PMCID: PMC6333893 DOI: 10.1074/jbc.ra118.005992] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 11/05/2018] [Indexed: 11/24/2022] Open
Abstract
The sesquiterpenoid juvenile hormone (JH) is vital to insect development and reproduction. Intracellular JH receptors have recently been established as basic helix-loop-helix transcription factor (bHLH)/PAS proteins in Drosophila melanogaster known as germ cell–expressed (Gce) and its duplicate paralog, methoprene-tolerant (Met). Upon binding JH, Gce/Met activates its target genes. Insects possess multiple native JH homologs whose molecular activities remain unexplored, and diverse synthetic compounds including insecticides exert JH-like effects. How the JH receptor recognizes its ligands is unknown. To determine which structural features define an active JH receptor agonist, we tested several native JHs and their nonnative geometric and optical isomers for the ability to bind the Drosophila JH receptor Gce, to induce Gce-dependent transcription, and to affect the development of the fly. Our results revealed high ligand stereoselectivity of the receptor. The geometry of the JH skeleton, dictated by two stereogenic double bonds, was the most critical feature followed by the presence of an epoxide moiety at a terminal position. The optical isomerism at carbon C11 proved less important even though Gce preferentially bound a natural JH enantiomer. The results of receptor-ligand–binding and cell-based gene activation assays tightly correlated with the ability of different geometric JH isomers to induce gene expression and morphogenetic effects in the developing insects. Molecular modeling supported the requirement for the proper double-bond geometry of JH, which appears to be its major selective mechanism. The strict stereoselectivity of Gce toward the natural hormone contrasts with the high potency of synthetic Gce agonists of disparate chemistries.
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Affiliation(s)
- Lenka Bittova
- From the Biology Center of the Czech Academy of Sciences, Institute of Entomology, Ceske Budejovice 370 05, Czech Republic and
| | - Pavel Jedlicka
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague 166 10, Czech Republic
| | - Martin Dracinsky
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague 166 10, Czech Republic
| | - Palani Kirubakaran
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague 166 10, Czech Republic
| | - Jiri Vondrasek
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague 166 10, Czech Republic
| | - Robert Hanus
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague 166 10, Czech Republic
| | - Marek Jindra
- From the Biology Center of the Czech Academy of Sciences, Institute of Entomology, Ceske Budejovice 370 05, Czech Republic and
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