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Kumar D, Budachetri K, Rikihisa Y, Karim S. Analysis of Amblyomma americanum microRNAs in response to Ehrlichia chaffeensis infection and their potential role in vectorial capacity. Front Cell Infect Microbiol 2024; 14:1427562. [PMID: 39086604 PMCID: PMC11288922 DOI: 10.3389/fcimb.2024.1427562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2024] [Accepted: 06/27/2024] [Indexed: 08/02/2024] Open
Abstract
Background MicroRNAs (miRNAs) represent a subset of small noncoding RNAs and carry tremendous potential for regulating gene expression at the post-transcriptional level. They play pivotal roles in distinct cellular mechanisms including inhibition of bacterial, parasitic, and viral infections via immune response pathways. Intriguingly, pathogens have developed strategies to manipulate the host's miRNA profile, fostering environments conducive to successful infection. Therefore, changes in an arthropod host's miRNA profile in response to pathogen invasion could be critical in understanding host-pathogen dynamics. Additionally, this area of study could provide insights into discovering new targets for disease control and prevention. The main objective of the present study is to investigate the functional role of differentially expressed miRNAs upon Ehrlichia chaffeensis, a tick-borne pathogen, infection in tick vector, Amblyomma americanum. Methods Small RNA libraries from uninfected and E. chaffeensis-infected Am. americanum midgut and salivary gland tissues were prepared using the Illumina Truseq kit. Small RNA sequencing data was analyzed using miRDeep2 and sRNAtoolbox to identify novel and known miRNAs. The differentially expressed miRNAs were validated using a quantitative PCR assay. Furthermore, a miRNA inhibitor approach was used to determine the functional role of selected miRNA candidates. Results The sequencing of small RNA libraries generated >147 million raw reads in all four libraries and identified a total of >250 miRNAs across the four libraries. We identified 23 and 14 differentially expressed miRNAs in salivary glands, and midgut tissues infected with E. chaffeensis, respectively. Three differentially expressed miRNAs (miR-87, miR-750, and miR-275) were further characterized to determine their roles in pathogen infection. Inhibition of target miRNAs significantly decreased the E. chaffeensis load in tick tissues, which warrants more in-depth mechanistic studies. Conclusions The current study identified known and novel miRNAs and suggests that interfering with these miRNAs may impact the vectorial capacity of ticks to harbor Ehrlichia. This study identified several new miRNAs for future analysis of their functions in tick biology and tick-pathogen interaction studies.
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Affiliation(s)
- Deepak Kumar
- School of Biological, Environmental, and Earth Sciences, The University of Southern Mississippi, Hattiesburg, MS, United States
| | - Khemraj Budachetri
- Laboratory of Molecular, Cellular, and Environmental Rickettsiology, Department of Veterinary Biosciences, College of Veterinary Medicine, Infectious Diseases Institute, The Ohio State University, Columbus, OH, United States
| | - Yasuko Rikihisa
- Laboratory of Molecular, Cellular, and Environmental Rickettsiology, Department of Veterinary Biosciences, College of Veterinary Medicine, Infectious Diseases Institute, The Ohio State University, Columbus, OH, United States
| | - Shahid Karim
- School of Biological, Environmental, and Earth Sciences, The University of Southern Mississippi, Hattiesburg, MS, United States
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Kumar D, Budachetri K, Rikihisa Y, Karim S. Analysis of Amblyomma americanum microRNAs in response to Ehrlichia chaffeensis infection and their potential role in vectorial capacity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.03.592465. [PMID: 38765993 PMCID: PMC11100627 DOI: 10.1101/2024.05.03.592465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Background MicroRNAs (miRNAs) represent a subset of small noncoding RNAs and carry tremendous potential for regulating gene expression at the post-transcriptional level. They play pivotal roles in distinct cellular mechanisms including inhibition of bacterial, parasitic, and viral infections via immune response pathways. Intriguingly, pathogens have developed strategies to manipulate the host's miRNA profile, fostering environments conducive to successful infection. Therefore, changes in an arthropod host's miRNA profile in response to pathogen invasion could be critical in understanding host-pathogen dynamics. Additionally, this area of study could provide insights into discovering new targets for disease control and prevention. The main objective of the present study is to investigate the functional role of differentially expressed miRNAs upon Ehrlichia chaffeensis, a tick-borne pathogen, infection in tick vector, Amblyomma americanum. Methods Small RNA libraries from uninfected and E. chaffeensis-infected Am. americanum midgut and salivary gland tissues were prepared using the Illumina Truseq kit. Small RNA sequencing data was analyzed using miRDeep2 and sRNAtoolbox to identify novel and known miRNAs. The differentially expressed miRNAs were validated using a quantitative PCR assay. Furthermore, a miRNA inhibitor approach was used to determine the functional role of selected miRNA candidates. Results The sequencing of small RNA libraries generated >147 million raw reads in all four libraries and identified a total of >250 miRNAs across the four libraries. We identified 23 and 14 differentially expressed miRNAs in salivary glands, and midgut tissues infected with E. chaffeensis, respectively. Three differentially expressed miRNAs (miR-87, miR-750, and miR-275) were further characterized to determine their roles in pathogen infection. Inhibition of target miRNAs significantly decreased the E. chaffeensis load in tick tissues, which warrants more in-depth mechanistic studies. Conclusions The current study identified known and novel miRNAs and suggests that interfering with these miRNAs may impact the vectorial capacity of ticks to harbor Ehrlichia. This study identified several new miRNAs for future analysis of their functions in tick biology and tick-pathogen interaction studies.
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Affiliation(s)
- Deepak Kumar
- School of Biological, Environmental, and Earth Sciences, The University of Southern Mississippi, Hattiesburg, MS 39406, USA
| | - Khemraj Budachetri
- Laboratory of Molecular, Cellular, and Environmental Rickettsiology, Department of Veterinary Biosciences, College of Veterinary Medicine, Infectious Diseases Institute, The Ohio State University, Columbus, OH, United States
| | - Yasuko Rikihisa
- Laboratory of Molecular, Cellular, and Environmental Rickettsiology, Department of Veterinary Biosciences, College of Veterinary Medicine, Infectious Diseases Institute, The Ohio State University, Columbus, OH, United States
| | - Shahid Karim
- School of Biological, Environmental, and Earth Sciences, The University of Southern Mississippi, Hattiesburg, MS 39406, USA
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Cano-Argüelles AL, Pérez-Sánchez R, Oleaga A. A microRNA profile of the saliva in the argasid ticks Ornithodoros erraticus and Ornithodoros moubata and prediction of specific target genes. Ticks Tick Borne Dis 2023; 14:102249. [PMID: 37689036 DOI: 10.1016/j.ttbdis.2023.102249] [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: 06/27/2023] [Revised: 08/29/2023] [Accepted: 08/30/2023] [Indexed: 09/11/2023]
Abstract
Ornithodoros erraticus and Ornithodoros moubata ticks are the main vectors of the agents of human relapsing fever (TBRF) and African swine fever (ASF) in the Mediterranean Basin and Africa, respectively. Tick saliva is crucial for complete tick feeding and pathogen transmission, as it contains numerous molecules such as proteins, lipids, and non-coding RNAs (ncRNA) including microRNAs (miRNA). MiRNAs are small ncRNAs capable of regulating the expression of their target messenger RNA (mRNA) leading to degradation or inhibition of its translation into protein. Research on miRNAs from ixodid ticks has revealed that miRNAs are involved in the regulation of different physiological processes of ticks, as well as in the modulation of host gene expression, immune response to tick bite and pathogen transmission. Regarding argasid ticks, there is not information about their miRNAs or their potential involvement in tick physiology and/or in the regulation of the tick-host-pathogen interactions. The aim of this work was to profile the miRNAs expressed in the saliva of O. erraticus and O. moubata, and the in silico prediction and functional analysis of their target genes in the swine host. As a whole, up to 72 conserved miRNAs families were identified in both species: 35 of them were shared and 23 and 14 families were unique to O. erraticus and O. moubata, respectively. The most abundant miRNAs families were mir-1, mir-10 and let-7 in O. erraticus and let-7, mir-252, mir-10 in O. moubata. Four miRNAs sequences of each species were validated by RT-qPCR confirming their presence in the saliva. Target gene prediction in the host (Sus scrofa) and functional analysis showed that the selected miRNAs are mainly involved in processes related to signal transduction, regulation of mRNA transcription and gene expression, synapse regulation, immune response, angiogenesis and vascular development. These results suggest that miRNAs could play an important role at the tick-host interface, providing new insights into this complex relationship that may contribute to a more precise selection of tick molecules for the development of therapeutic and immune strategies to control tick infestations and tick-borne pathogens.
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Affiliation(s)
- Ana Laura Cano-Argüelles
- Parasitología Animal, Instituto de Recursos Naturales y Agrobiología de Salamanca (IRNASA, CSIC), Cordel de Merinas, 40-52, Salamanca 37008, Spain.
| | - Ricardo Pérez-Sánchez
- Parasitología Animal, Instituto de Recursos Naturales y Agrobiología de Salamanca (IRNASA, CSIC), Cordel de Merinas, 40-52, Salamanca 37008, Spain
| | - Ana Oleaga
- Parasitología Animal, Instituto de Recursos Naturales y Agrobiología de Salamanca (IRNASA, CSIC), Cordel de Merinas, 40-52, Salamanca 37008, Spain.
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Zeng Q, Long G, Yang H, Zhou C, Yang X, Wang Z, Jin D. SfDicer1 participates in the regulation of molting development and reproduction in the white-backed planthopper, Sogatella furcifera. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2023; 191:105347. [PMID: 36963929 DOI: 10.1016/j.pestbp.2023.105347] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 01/12/2023] [Accepted: 01/21/2023] [Indexed: 06/18/2023]
Abstract
Dicer1 plays a vital role in the formation of mature miRNA and regulates the growth, development, and reproduction of insects. However, it remains to be clarified whether Dicer1 is involved in regulating the biological processes underlying molting and reproduction of Sogatella furcifera (Horváth). Herein, SfDicer1 expression fluctuated in all the developmental stages of S. furcifera and increased as molting progressed. SfDicer1 exhibited high expression in the integument, head, fat body, and ovary of the insects. SfDicer1 dsRNA injection into 1-day-old fourth instar nymphs of S. furcifera substantially decreased the survival rate and expression of the lethal phenotypes of wing malformation and molting defects and significantly inhibited the expression of four conserved miRNAs associated with molting development. Subsequently, following the knockdown of SfDicer1 in the newly emerged (1-12 h) females of S. furcifera, SfVg and SfVgR expression levels were decreased, thereby delaying ovarian development, decreasing the number of eggs, and considerably reducing the hatching rate compared with those of the control. Finally, after silencing SfDicer1 for 48 h, the comparative transcriptome analysis of differentially expressed genes revealed considerable enrichment of the Gene Ontology terms structural constituent of cuticle, structural molecule activity, chitin metabolic process, amino sugar metabolic process, and intracellular anatomical structure, indicating that SfDicer1 inhibition affects the transcription of genes associated with growth and development. Thus, our results suggest that SfDicer1 is essential in the molting, survival, ovarian development, and fecundity of S. furcifera and is a suitable target gene for developing an RNAi-based strategy targeting the most destructive rice insect pest.
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Affiliation(s)
- Qinghui Zeng
- Institute of Entomology, Guizhou University; Guizhou Provincial Key Laboratory for Agricultural Pest Management of Mountainous Regions, and Scientific Observing and Experimental Station of Crop Pests in Guiyang, Ministry of Agriculture and Rural Affairs of the People's Republic of China, Guiyang 550025, China
| | - Guiyun Long
- Institute of Entomology, Guizhou University; Guizhou Provincial Key Laboratory for Agricultural Pest Management of Mountainous Regions, and Scientific Observing and Experimental Station of Crop Pests in Guiyang, Ministry of Agriculture and Rural Affairs of the People's Republic of China, Guiyang 550025, China
| | - Hong Yang
- Institute of Entomology, Guizhou University; Guizhou Provincial Key Laboratory for Agricultural Pest Management of Mountainous Regions, and Scientific Observing and Experimental Station of Crop Pests in Guiyang, Ministry of Agriculture and Rural Affairs of the People's Republic of China, Guiyang 550025, China.
| | - Cao Zhou
- College of Life Sciences, Chongqing Normal University, Chongqing 401331, China
| | - Xibin Yang
- Institute of Entomology, Guizhou University; Guizhou Provincial Key Laboratory for Agricultural Pest Management of Mountainous Regions, and Scientific Observing and Experimental Station of Crop Pests in Guiyang, Ministry of Agriculture and Rural Affairs of the People's Republic of China, Guiyang 550025, China
| | - Zhao Wang
- College of Environment and Life Sciences, Kaili University, Kaili 556011, China
| | - Daochao Jin
- Institute of Entomology, Guizhou University; Guizhou Provincial Key Laboratory for Agricultural Pest Management of Mountainous Regions, and Scientific Observing and Experimental Station of Crop Pests in Guiyang, Ministry of Agriculture and Rural Affairs of the People's Republic of China, Guiyang 550025, China
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de la Fuente J, Kocan KM. The Impact of RNA Interference in Tick Research. Pathogens 2022; 11:pathogens11080827. [PMID: 35894050 PMCID: PMC9394339 DOI: 10.3390/pathogens11080827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 07/21/2022] [Accepted: 07/22/2022] [Indexed: 11/16/2022] Open
Abstract
Over the past two decades, RNA interference (RNAi) in ticks, in combination with omics technologies, have greatly advanced the discovery of tick gene and molecular function. While mechanisms of RNAi were initially elucidated in plants, fungi, and nematodes, the classic 2002 study by Aljamali et al. was the first to demonstrate RNAi gene silencing in ticks. Subsequently, applications of RNAi have led to the discovery of genes that impact tick function and tick-host-pathogen interactions. RNAi will continue to lead to the discovery of an array of tick genes and molecules suitable for the development of vaccines and/or pharmacologic approaches for tick control and the prevention of pathogen transmission.
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Affiliation(s)
- José de la Fuente
- SaBio, Instituto de Investigación en Recursos Cinegéticos IREC-CSIC-UCLM-JCCM, Ronda de Toledo s/n, 13005 Ciudad Real, Spain
- The Department of Veterinary Pathobiology, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK 74078, USA;
- Correspondence: or
| | - Katherine M. Kocan
- The Department of Veterinary Pathobiology, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK 74078, USA;
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DeRaedt S, Bierman A, van Heusden P, Richards C, Christoffels A. microRNA profile of Hermetia illucens (black soldier fly) and its implications on mass rearing. PLoS One 2022; 17:e0265492. [PMID: 35298540 PMCID: PMC8929568 DOI: 10.1371/journal.pone.0265492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 03/02/2022] [Indexed: 11/18/2022] Open
Abstract
The growing demands on protein producers and the dwindling available resources have made Hermetia illucens (the black soldier fly, BSF) an economically important species. Insights into the genome of this insect will better allow for robust breeding protocols, and more efficient production to be used as a replacement of animal feed protein. The use of microRNA as a method to understand how gene regulation allows insect species to adapt to changes in their environment, has been established in multiple species. The baseline and life stage expression levels established in this study, allow for insight into the development and sex-linked microRNA regulation in BSF. To accomplish this, microRNA was extracted and sequenced from 15 different libraries with each life stage in triplicate. Of the total 192 microRNAs found, 168 were orthologous to known arthropod microRNAs and 24 microRNAs were unique to BSF. Twenty-six of the 168 microRNAs conserved across arthropods had a statistically significant (p < 0.05) differential expression between Egg to Larval stages. The development from larva to pupa was characterized by 16 statistically significant differentially expressed microRNA. Seven and 9 microRNA were detected as statistically significant between pupa to adult female and pupa to adult male, respectively. All life stages had a nearly equal split between up and down regulated microRNAs. Ten of the unique 24 miRNA were detected exclusively in one life stage. The egg life stage expressed five microRNA (hil-miR-m, hil-miR-p, hil-miR-r, hil-miR-s, and hil-miR-u) not seen in any other life stages. The female adult and pupa life stages expressed one miRNA each hil-miR-h and hil-miR-ac respectively. Both male and female adult life stages expressed hil-miR-a, hil-miR-b, and hil-miR-y. There were no unique microRNAs found only in the larva stage. Twenty-two microRNAs with 56 experimentally validated target genes in the closely related Drosophila melanogaster were identified. Thus, the microRNA found display the unique evolution of BSF, along with the life stages and potential genes to target for robust mass rearing. Understanding of the microRNA expression in BSF will further their use in the crucial search for alternative and sustainable protein sources.
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Affiliation(s)
- Sarah DeRaedt
- South African National Bioinformatics Institute, South African Medical Research Council Bioinformatics Unit, The University of the Western Cape, Bellville, Western Cape, South Africa
| | - Anandi Bierman
- AgriProtein Technologies (Pty) Limited, Philippi, Western Cape, South Africa
| | - Peter van Heusden
- South African National Bioinformatics Institute, South African Medical Research Council Bioinformatics Unit, The University of the Western Cape, Bellville, Western Cape, South Africa
| | - Cameron Richards
- AgriProtein Technologies (Pty) Limited, Philippi, Western Cape, South Africa
| | - Alan Christoffels
- South African National Bioinformatics Institute, South African Medical Research Council Bioinformatics Unit, The University of the Western Cape, Bellville, Western Cape, South Africa
- * E-mail:
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Lu X, Zhang Z, Yuan D, Zhou Y, Cao J, Zhang H, da Silva Vaz I, Zhou J. The ecdysteroid receptor regulates salivary gland degeneration through apoptosis in Rhipicephalus haemaphysaloides. Parasit Vectors 2021; 14:612. [PMID: 34930413 PMCID: PMC8686549 DOI: 10.1186/s13071-021-05052-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 10/01/2021] [Indexed: 11/16/2022] Open
Abstract
Background It is well established that ecdysteroid hormones play an important role in arthropod development and reproduction, mediated by ecdysteroid receptors. Ticks are obligate hematophagous arthropods and vectors of pathogens. The salivary gland plays an essential role in tick growth and reproduction and in the transmission of pathogens to vertebrate hosts. During tick development, the salivary gland undergoes degeneration triggered by ecdysteroid hormones and activated by apoptosis. However, it is unknown how the ecdysteroid receptor and apoptosis regulate salivary gland degeneration. Here, we report the functional ecdysteroid receptor (a heterodimer of the ecdysone receptor [EcR] and ultraspiracle [USP]) isolated from the salivary gland of the tick Rhipicephalus haemaphysaloides and explore the molecular mechanism of ecdysteroid receptor regulation of salivary gland degeneration. Methods The full length of RhEcR and RhUSP open reading frames (ORFs) was obtained from the transcriptome. The RhEcR and RhUSP proteins were expressed in a bacterial heterologous system, Escherichia coli. Polyclonal antibodies were produced against synthetic peptides and were able to recognize recombinant and native proteins. Quantitative real-time PCR and western blot were used to detect the distribution of RhEcR, RhUSP, and RhCaspases in the R. haemaphysaloides organs. A proteomics approach was used to analyze the expression profiles of the ecdysteroid receptors, RhCaspases, and other proteins. To analyze the function of the ecdysteroid receptor, RNA interference (RNAi) was used to silence the genes in adult female ticks. Finally, the interaction of RhEcR and RhUSP was identified by heterologous co-expression assays in HEK293T cells. Results We identified the functional ecdysone receptor (RhEcR/RhUSP) of 20-hydroxyecdysone from the salivary gland of the tick R. haemaphysaloides. The RhEcR and RhUSP genes have three and two isoforms, respectively, and belong to a nuclear receptor family but with variable N-terminal A/B domains. The RhEcR gene silencing inhibited blood-feeding, blocked engorgement, and restrained salivary gland degeneration, showing the biological role of the RhEcR gene in ticks. In the ecdysteroid signaling pathway, RhEcR silencing inhibited salivary gland degeneration by suppressing caspase-dependent apoptosis. The heterologous expression in mammalian HEK293T cells showed that RhEcR1 interacts with RhUSP1 and induces caspase-dependent apoptosis. Conclusions These data show that RhEcR has an essential role in tick physiology and represents a putative target for the control of ticks and tick-borne diseases. Graphical Abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13071-021-05052-2.
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Affiliation(s)
- Xiaojuan Lu
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, China
| | - Zhipeng Zhang
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, China
| | - Dongqi Yuan
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, China
| | - Yongzhi Zhou
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, China
| | - Jie Cao
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, China
| | - Houshuang Zhang
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, China
| | - Itabajara da Silva Vaz
- Centro de Biotecnologia, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, RS, Brazil
| | - Jinlin Zhou
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, China.
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Huang DY, Xia XL, Huang R, Li S, Yuan DW, Liu SN. The steroid-induced microRNA let-7 regulates developmental growth by targeting cdc7 in the Drosophila fat body. INSECT SCIENCE 2021; 28:1621-1632. [PMID: 33089948 DOI: 10.1111/1744-7917.12878] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 09/30/2020] [Accepted: 10/11/2020] [Indexed: 06/11/2023]
Abstract
In insects, 20-hydroxyecdysone (20E) limits systemic growth by triggering developmental transitions. Previous studies have shown that 20E-induced let-7 exhibits crosstalk with the cell cycle. Here, we examined the underlying molecular mechanisms and physiological functions of 20E-induced let-7 in the fat body, an organ for energy storage and nutrient mobilization which plays a critical role in the larval growth. First, the overexpression of let-7 decreased the body size and led to the reduction of both nucleolus and cell sizes in the larval fat body. In contrast, the overexpression of let-7-Sponge increased the nucleolus and cell sizes. Moreover, we found that cdc7, encoding a conserved protein kinase that controls the endocycle, is a target of let-7. Notably, the mutation of cdc7 in the fat body resulted in growth defects. Overall, our findings revealed a novel role of let-7 in the control of endoreduplication-related growth during larval-prepupal transition in Drosophila.
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Affiliation(s)
- Dan-Yan Huang
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Xiao-Ling Xia
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Run Huang
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Sheng Li
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Dong-Wei Yuan
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou, 510631, China
| | - Su-Ning Liu
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou, 510631, China
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