1
|
Zarrabian M, Sherif SM. Silence is not always golden: A closer look at potential environmental and ecotoxicological impacts of large-scale dsRNA application. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 950:175311. [PMID: 39122031 DOI: 10.1016/j.scitotenv.2024.175311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2024] [Revised: 08/02/2024] [Accepted: 08/04/2024] [Indexed: 08/12/2024]
Abstract
RNA interference (RNAi) technology has emerged as a pivotal strategy in sustainable pest management, offering a targeted approach that significantly mitigates the environmental and health risks associated with traditional insecticides. Originally implemented through genetically modified organisms (GMOs) to produce specific RNAi constructs, the technology has evolved in response to public and regulatory concerns over GMOs. This evolution has spurred the development of non-transgenic RNAi applications such as spray-induced gene silencing (SIGS), which employs double-stranded RNA (dsRNA) to silence pest genes directly without altering the plant's genetic makeup. Despite its advantages in specificity and reduced ecological footprint, SIGS faces significant obstacles, particularly the instability of dsRNA in field conditions, which limits its practical efficacy. To overcome these limitations, innovative delivery mechanisms have been developed. These include nanotechnology-based systems, minicells, and nanovesicles, which are designed to protect dsRNA from degradation and enhance its delivery to target organisms. While these advancements have improved the stability and application efficiency of dsRNA, comprehensive assessments of their environmental safety and the potential for increased exposure risks to non-target organisms remain incomplete. This comprehensive review aims to elucidate the environmental fate of dsRNA and evaluate the potential risks associated with its widespread application on non-target organisms, encompassing soil microorganisms, beneficial insects, host plants, and mammals. The objective is to establish a more refined framework for RNAi risk assessment within environmental and ecotoxicological contexts, thereby fostering the development of safer, non-transgenic RNAi-based pest control strategies.
Collapse
Affiliation(s)
- Mohammad Zarrabian
- Virginia Tech, School of Plant and Environmental Sciences, Alson H. Smith Jr. Agricultural Research, and Extension Center, Winchester, VA 22602, United States
| | - Sherif M Sherif
- Virginia Tech, School of Plant and Environmental Sciences, Alson H. Smith Jr. Agricultural Research, and Extension Center, Winchester, VA 22602, United States.
| |
Collapse
|
2
|
Lebenzon JE, Toxopeus J. Knock down to level up: Reframing RNAi for invertebrate ecophysiology. Comp Biochem Physiol A Mol Integr Physiol 2024; 297:111703. [PMID: 39029617 DOI: 10.1016/j.cbpa.2024.111703] [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: 02/21/2024] [Revised: 07/16/2024] [Accepted: 07/16/2024] [Indexed: 07/21/2024]
Abstract
Comparative ecophysiologists strive to understand physiological problems in non-model organisms, but molecular tools such as RNA interference (RNAi) are under-used in our field. Here, we provide a framework for invertebrate ecophysiologists to use RNAi to answer questions focused on physiological processes, rather than as a tool to investigate gene function. We specifically focus on non-model invertebrates, in which the use of other genetic tools (e.g., genetic knockout lines) is less likely. We argue that because RNAi elicits a temporary manipulation of gene expression, and resources to carry out RNAi are technically and financially accessible, it is an effective tool for invertebrate ecophysiologists. We cover the terminology and basic mechanisms of RNA interference as an accessible introduction for "non-molecular" physiologists, include a suggested workflow for identifying RNAi gene targets and validating biologically relevant gene knockdowns, and present a hypothesis-testing framework for using RNAi to answer common questions in the realm of invertebrate ecophysiology. This review encourages invertebrate ecophysiologists to use these tools and workflows to explore physiological processes and bridge genotypes to phenotypes in their animal(s) of interest.
Collapse
Affiliation(s)
- Jacqueline E Lebenzon
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4.
| | - Jantina Toxopeus
- Department of Biology, St. Francis Xavier University, 2321 Notre Dame Ave, Antigonish, NS, Canada B2G 2W5
| |
Collapse
|
3
|
Lv D, Kassen K, Men C, Yang X, Pan D, Wang X, Wang N, Wang P, Yuan X, Li Y. Trypsin-encoding gene function of efficient star polycation nanomaterial-mediated dsRNA feeding delivery system of Grapholita molesta. PEST MANAGEMENT SCIENCE 2024. [PMID: 38970236 DOI: 10.1002/ps.8289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 05/28/2024] [Accepted: 06/23/2024] [Indexed: 07/08/2024]
Abstract
BACKGROUND Grapholita molesta is an important and harmful fruit pest worldwide, with widespread feeding hosts. Trypsin, an indispensable hydrolytic digestive protease in the insect gut, is crucial in digestion, growth and development. We analyzed the characteristics of the trypsin-encoding genes, screened for the optimal dose of RNAi mediated by nanocarriers, and investigated various indices of larval growth and development of G. molesta. RESULTS Gut content (GC) and RNase A degraded double-stranded RNA (dsRNA), with a faster degradation rate at higher concentrations. Star polycation (SPc) nanomaterials protected dsGFP from degradation by anion-cation binding and did not migrate through agarose gel. The key conserved motifs of the trypsin-encoding genes were similar, exhibiting high homology with those in other lepidopteran insects. An interference efficiency of ≈70% was achieved with SPc nanomaterial-mediated RNA interference with 0.05 μg dsRNA. The efficiency of continuous interference was stable. Trypsin activity, body weight of 8-day-old larvae, pupal weight and emergence rate were significantly reduced, and the larval stage was significantly prolonged. CONCLUSION The investigated trypsin gene is a key target gene in the growth and development of G. molesta. We investigated the efficiency and convenience of feeding SPc nanomaterials in a functional study of insects. Our results provide valuable data for the development of efficient trypsin-targeting pesticides. © 2024 Society of Chemical Industry.
Collapse
Affiliation(s)
- Dongbiao Lv
- Key Laboratory of Plant Protection Resources and Pest Management of Ministry of Education, Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau of Ministry of Agriculture and Rural Affairs, College of Plant Protection, Northwest A&F University, Yangling, China
| | - Kuanysh Kassen
- Key Laboratory of Plant Protection Resources and Pest Management of Ministry of Education, Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau of Ministry of Agriculture and Rural Affairs, College of Plant Protection, Northwest A&F University, Yangling, China
| | - Chunxiao Men
- Key Laboratory of Plant Protection Resources and Pest Management of Ministry of Education, Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau of Ministry of Agriculture and Rural Affairs, College of Plant Protection, Northwest A&F University, Yangling, China
| | - Xiaoyan Yang
- Key Laboratory of Plant Protection Resources and Pest Management of Ministry of Education, Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau of Ministry of Agriculture and Rural Affairs, College of Plant Protection, Northwest A&F University, Yangling, China
| | - Dandan Pan
- Key Laboratory of Plant Protection Resources and Pest Management of Ministry of Education, Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau of Ministry of Agriculture and Rural Affairs, College of Plant Protection, Northwest A&F University, Yangling, China
| | - Xuecheng Wang
- Key Laboratory of Plant Protection Resources and Pest Management of Ministry of Education, Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau of Ministry of Agriculture and Rural Affairs, College of Plant Protection, Northwest A&F University, Yangling, China
| | - Nan Wang
- Key Laboratory of Plant Protection Resources and Pest Management of Ministry of Education, Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau of Ministry of Agriculture and Rural Affairs, College of Plant Protection, Northwest A&F University, Yangling, China
| | - Ping Wang
- Department of Entomology, Cornell University, Geneva, NY, USA
| | - Xiangqun Yuan
- Key Laboratory of Plant Protection Resources and Pest Management of Ministry of Education, Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau of Ministry of Agriculture and Rural Affairs, College of Plant Protection, Northwest A&F University, Yangling, China
| | - Yiping Li
- Key Laboratory of Plant Protection Resources and Pest Management of Ministry of Education, Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau of Ministry of Agriculture and Rural Affairs, College of Plant Protection, Northwest A&F University, Yangling, China
| |
Collapse
|
4
|
Koo J, Palli SR. Recent advances in understanding of the mechanisms of RNA interference in insects. INSECT MOLECULAR BIOLOGY 2024. [PMID: 38957135 DOI: 10.1111/imb.12941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Accepted: 06/20/2024] [Indexed: 07/04/2024]
Abstract
We highlight the recent 5 years of research that contributed to our understanding of the mechanisms of RNA interference (RNAi) in insects. Since its first discovery, RNAi has contributed enormously as a reverse genetic tool for functional genomic studies. RNAi is also being used in therapeutics, as well as agricultural crop and livestock production and protection. Yet, for the wider application of RNAi, improvement of its potency and delivery technologies is needed. A mechanistic understanding of every step of RNAi, from cellular uptake of RNAi trigger molecules to targeted mRNA degradation, is key for developing an efficient strategy to improve RNAi technology. Insects provide an excellent model for studying the mechanism of RNAi due to species-specific variations in RNAi efficiency. This allows us to perform comparative studies in insect species with different RNAi sensitivity. Understanding the mechanisms of RNAi in different insects can lead to the development of better strategies to improve RNAi and its application to manage agriculturally and medically important insects.
Collapse
Affiliation(s)
- Jinmo Koo
- Department of Entomology, Gatton-Martin College of Agriculture, University of Kentucky, Lexington, Kentucky, USA
| | - Subba Reddy Palli
- Department of Entomology, Gatton-Martin College of Agriculture, University of Kentucky, Lexington, Kentucky, USA
| |
Collapse
|
5
|
Salman Hameed M, Ren Y, Tuda M, Basit A, Urooj N. Role of Argonaute proteins in RNAi pathway in Plutella xylostella: A review. Gene 2024; 903:148195. [PMID: 38295911 DOI: 10.1016/j.gene.2024.148195] [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: 12/04/2023] [Accepted: 01/18/2024] [Indexed: 02/04/2024]
Abstract
Argonaute (Ago) proteins act as key elements in RNA interference (RNAi) pathway, orchestrating the intricate machinery of gene regulation within eukaryotic cells. Within the RNAi pathway, small RNA molecules, including microRNA (miRNA), small interfering RNA (siRNA), and PIWI-interacting RNA (piRNA), collaborate with Ago family member proteins such as Ago1, Ago2, and Ago3 to form the RNA-induced silencing complex (RISC). This RISC complex, in turn, either cleaves the target mRNA or inhibits the process of protein translation. The precise contributions of Ago proteins have been well-established in numerous animals and plants, although they still remain unclear in some insect species. This review aims to shed light on the specific roles played by Ago proteins within the RNAi mechanism in a destructive lepidopteran pest, the diamondback moth (Plutella xylostella). Furthermore, we explore the potential of double-stranded RNA (dsRNA)-mediated RNAi as a robust genetic tool in pest management strategies. Through an in-depth examination of Ago proteins and dsRNA-mediated RNAi, this review seeks to contribute to our understanding of innovative approaches for controlling this pest and potentially other insect species of agricultural significance.
Collapse
Affiliation(s)
- Muhammad Salman Hameed
- National Key Laboratory of Green Pesticide, International Joint Research Center for Intelligent Biosensor Technology and Health, Central China Normal University, Wuhan 430079, China.
| | - Yanliang Ren
- National Key Laboratory of Green Pesticide, International Joint Research Center for Intelligent Biosensor Technology and Health, Central China Normal University, Wuhan 430079, China.
| | - Midori Tuda
- Institute of Biological Control, Faculty of Agriculture, Kyushu University, Fukuoka 819-0395, Japan
| | - Abdul Basit
- Institute of Entomology, Guizhou University Guiyang 550025, Guizhou China
| | - Nida Urooj
- Department of Business Administrative, Bahaudin Zakriya University, Multan, Pakistan
| |
Collapse
|
6
|
Shu Q, Liu GC, He JW, Hu P, Dong ZW, Zhao RP, Zhang HR, Li XY. RNAi efficiency is enhanced through knockdown of double-stranded RNA-degrading enzymes in butterfly Papilio xuthus. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2024; 115:e22113. [PMID: 38628056 DOI: 10.1002/arch.22113] [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: 12/08/2023] [Revised: 03/27/2024] [Accepted: 04/08/2024] [Indexed: 04/19/2024]
Abstract
The efficiency of RNA interference (RNAi) has always limited the research on the phenotype innovation of Lepidoptera insects. Previous studies have found that double-stranded RNA-degrading enzyme (dsRNase) is an important factor in RNAi efficiency, but there have been no relevant reports in butterflies (Papilionoidea). Papilio xuthus is one of the important models in butterflies with an extensive experimental application value. To explore the effect of dsRNase in the RNAi efficiency on butterflies, six dsRNase genes (PxdsRNase 1-6) were identified in P. xuthus genome, and their dsRNA-degrading activities were subsequently detected by ex vivo assays. The result shows that the dsRNA-degrading ability of gut content (<1 h) was higher than hemolymph content (>12 h). We then investigated the expression patterns of these PxdsRNase genes during different tissues and developmental stages, and related RNAi experiments were carried out. Our results show that different PxdsRNase genes had different expression levels at different developmental stages and tissues. The expression of PxdsRNase2, PxdsRNase3, and PxdsRNase6 were upregulated significantly through dsGFP injection, and PxdsRNase genes can be silenced effectively by injecting their corresponding dsRNA. RNAi-of-RNAi studies with PxEbony, which acts as a reporter gene, observed that silencing PxdsRNase genes can increase RNAi efficiency significantly. These results confirm that silencing dsRNase genes can improve RNAi efficiency in P. xuthus significantly, providing a reference for the functional study of insects such as butterflies with low RNAi efficiency.
Collapse
Affiliation(s)
- Qian Shu
- Yunnan Agricultural University College of Plant Protection, Kunming, Yunnan, China
| | - Gui-Chun Liu
- Key Laboratory of Genetic Evolution & Animal Models, Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Jin-Wu He
- Key Laboratory of Genetic Evolution & Animal Models, Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Ping Hu
- Key Laboratory of Genetic Evolution & Animal Models, Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Zhi-Wei Dong
- Key Laboratory of Genetic Evolution & Animal Models, Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Ruo-Ping Zhao
- Key Laboratory of Genetic Evolution & Animal Models, Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Hong-Rui Zhang
- Yunnan Agricultural University College of Plant Protection, Kunming, Yunnan, China
| | - Xue-Yan Li
- Key Laboratory of Genetic Evolution & Animal Models, Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
| |
Collapse
|
7
|
Koo J, Zhu GH, Palli SR. CRISPR-Cas9 mediated dsRNase knockout improves RNAi efficiency in the fall armyworm. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2024; 200:105839. [PMID: 38582601 DOI: 10.1016/j.pestbp.2024.105839] [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: 12/27/2023] [Revised: 02/15/2024] [Accepted: 02/21/2024] [Indexed: 04/08/2024]
Abstract
Lepidopteran insects are refractory to RNA interference (RNAi) response, especially to orally delivered double-stranded RNA (dsRNA). High nuclease activity in the midgut lumen is proposed as one of the major reasons for RNAi insensitivity. We identified three dsRNase genes highly expressed in the midgut of fall armyworm (FAW), Spodoptera frugiperda. The genomic region harboring those three dsRNase genes was deleted using the CRISPR-Cas9-mediated genome editing method. A homozygous line with deletion of three dsRNase genes was produced. dsRNA degradation by midgut lumen contents of mutant larvae was lower than in wild-type larvae. Feeding dsRNA targeting the inhibitor of apoptosis (IAP) gene increased knockdown of the target gene and mortality in mutants compared to wild-type larvae. These results suggest that dsRNases in the midgut contribute to RNAi inefficiency in FAW. Formulations that protect dsRNA from dsRNase degradation may improve RNAi efficiency in FAW and other lepidopteran insects.
Collapse
Affiliation(s)
- Jinmo Koo
- Department of Entomology, College of Agriculture, University of Kentucky, Lexington, KY 40546, USA
| | - Guan-Heng Zhu
- Department of Entomology, College of Agriculture, University of Kentucky, Lexington, KY 40546, USA
| | - Subba Reddy Palli
- Department of Entomology, College of Agriculture, University of Kentucky, Lexington, KY 40546, USA.
| |
Collapse
|
8
|
Zhou X, Wei J, Ge H, Guan D, Li H, Zhang H, Zheng Y, Qian K, Wang J. Functional Characterization and Putative Regulatory Mechanism of an RNAi Efficiency-Related Nuclease (REase) in the Fall Armyworm, Spodoptera frugiperda. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:3973-3983. [PMID: 38361393 DOI: 10.1021/acs.jafc.3c08665] [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: 02/17/2024]
Abstract
The lepidopteran-specific RNAi efficiency-related nuclease (REase) has been shown to contribute to double-strand RNA (dsRNA) degradation in several lepidopteran insects. However, little is known about its regulatory mechanism. In this study, we identified and characterized SfREase in Spodoptera frugiperda. The exposure of the third-instar larvae to dsEGFP and high temperature led to the upregulation of SfREase, whereas starvation treatment resulted in the downregulation of SfREase. Further experiments revealed that dsRNA degraded more slowly in the hemolymph or midgut fluid extracted from dsSfREase-injected or dsSfREase-ingested larvae compared with those from dsEGFP-treated larvae, and the recombinant SfREase degraded dsRNA in a concentration-dependent manner. Additionally, the knockdown of SfREase improved RNAi efficiency. Finally, both RNAi and dual-luciferase reporter assay in Sf9 cells revealed that SfREase is negatively regulated by FOXO. These data provide insights into the function and regulatory mechanism of REase and have applied implications for the development of an RNAi-based control strategy of S. frugiperda.
Collapse
Affiliation(s)
- Xiaoyang Zhou
- College of Plant Protection, Yangzhou University, Yangzhou 225009, China
| | - Jiaping Wei
- College of Plant Protection, Yangzhou University, Yangzhou 225009, China
| | - Huichen Ge
- College of Plant Protection, Yangzhou University, Yangzhou 225009, China
| | - Daojie Guan
- College of Plant Protection, Yangzhou University, Yangzhou 225009, China
| | - Hai Li
- College of Plant Protection, Yangzhou University, Yangzhou 225009, China
| | - Hainan Zhang
- College of Plant Protection, Yangzhou University, Yangzhou 225009, China
| | - Yang Zheng
- College of Plant Protection, Yangzhou University, Yangzhou 225009, China
| | - Kun Qian
- College of Plant Protection, Yangzhou University, Yangzhou 225009, China
| | - Jianjun Wang
- College of Plant Protection, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education, Yangzhou University, Yangzhou 225009, China
| |
Collapse
|
9
|
Ortolá B, Daròs JA. RNA Interference in Insects: From a Natural Mechanism of Gene Expression Regulation to a Biotechnological Crop Protection Promise. BIOLOGY 2024; 13:137. [PMID: 38534407 DOI: 10.3390/biology13030137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 02/14/2024] [Accepted: 02/19/2024] [Indexed: 03/28/2024]
Abstract
Insect pests rank among the major limiting factors in agricultural production worldwide. In addition to direct effect on crops, some phytophagous insects are efficient vectors for plant disease transmission. Large amounts of conventional insecticides are required to secure food production worldwide, with a high impact on the economy and environment, particularly when beneficial insects are also affected by chemicals that frequently lack the desired specificity. RNA interference (RNAi) is a natural mechanism gene expression regulation and protection against exogenous and endogenous genetic elements present in most eukaryotes, including insects. Molecules of double-stranded RNA (dsRNA) or highly structured RNA are the substrates of cellular enzymes to produce several types of small RNAs (sRNAs), which play a crucial role in targeting sequences for transcriptional or post-transcriptional gene silencing. The relatively simple rules that underlie RNAi regulation, mainly based in Watson-Crick complementarity, have facilitated biotechnological applications based on these cellular mechanisms. This includes the promise of using engineered dsRNA molecules, either endogenously produced in crop plants or exogenously synthesized and applied onto crops, as a new generation of highly specific, sustainable, and environmentally friendly insecticides. Fueled on this expectation, this article reviews current knowledge about the RNAi pathways in insects, and some other applied questions such as production and delivery of recombinant RNA, which are critical to establish RNAi as a reliable technology for insect control in crop plants.
Collapse
Affiliation(s)
- Beltrán Ortolá
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-Universitat Politècnica de València, 46022 Valencia, Spain
| | - José-Antonio Daròs
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-Universitat Politècnica de València, 46022 Valencia, Spain
| |
Collapse
|
10
|
Zhang JY, Zhao J, Zhu-Salzman K, Ji QQ, Jiang YP, Xiao LB, Xu DJ, Xu GC, Ge LQ, Tan YA. Gene cloning, protein expression, and enzymatic characterization of a double-stranded RNA degrading enzyme in Apolygus lucorum. INSECT SCIENCE 2024; 31:119-133. [PMID: 37287390 DOI: 10.1111/1744-7917.13211] [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: 12/09/2022] [Revised: 03/27/2023] [Accepted: 04/02/2023] [Indexed: 06/09/2023]
Abstract
RNA interference (RNAi) is a powerful tool that post-transcriptionally silences target genes in eukaryotic cells. However, silencing efficacy varies greatly among different insect species. Recently, we met with little success when attempting to knock down genes in the mirid bug Apolygus lucorum via dsRNA injection. The disappearance of double-stranded RNA (dsRNA) could be a potential factor that restricts RNAi efficiency. Here, we found that dsRNA can be degraded in midgut fluids, and a dsRNase of A. lucorum (AldsRNase) was identified and characterized. Sequence alignment indicated that its 6 key amino acid residues and the Mg2+ -binding site were similar to those of other insects' dsRNases. The signal peptide and endonuclease non-specific domain shared high sequence identity with the brown-winged green stinkbug Plautia stali dsRNase. AldsRNase showed high salivary gland and midgut expression and was continuously expressed through the whole life cycle, with peaks at the 4th instar ecdysis in the whole body. The purified AldsRNase protein obtained by heterologously expressed can rapidly degrade dsRNA. When comparing the substrate specificity of AldsRNase, 3 specific substrates (dsRNA, small interfering RNA, and dsDNA) were all degraded, and the most efficient degradation is dsRNA. Subsequently, immunofluorescence revealed that AldsRNase was expressed in the cytoplasm of midgut cells. Through cloning and functional study of AldsRNase, the enzyme activity and substrate specificity of the recombinant protein, as well as the subcellular localization of nuclease, the reason for the disappearance of dsRNA was explained, which was useful in improving RNAi efficiency in A. lucorum and related species.
Collapse
Affiliation(s)
- Jie-Yu Zhang
- College of Plant Protection, Yangzhou University, Yangzhou, Jiangsu Province, China
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu Province, China
| | - Jing Zhao
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu Province, China
| | - Keyan Zhu-Salzman
- Department of Entomology, Texas A&M University, College Station, TX, USA
| | - Qin-Qin Ji
- Taizhou Customs of the People's Republic of China, Taizhou, Jiangsu Province, China
| | - Yi-Ping Jiang
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu Province, China
| | - Liu-Bin Xiao
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu Province, China
| | - De-Jin Xu
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu Province, China
| | - Guang-Chun Xu
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu Province, China
| | - Lin-Quan Ge
- College of Plant Protection, Yangzhou University, Yangzhou, Jiangsu Province, China
| | - Yong-An Tan
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu Province, China
| |
Collapse
|
11
|
Bai M, Liu ZL, Zhou YY, Xu QX, Liu TX, Tian HG. Influence of diverse storage conditions of double-stranded RNA in vitro on the RNA interference efficiency in vivo insect Tribolium castaneum. PEST MANAGEMENT SCIENCE 2023; 79:45-54. [PMID: 36086883 DOI: 10.1002/ps.7171] [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: 05/20/2022] [Revised: 08/10/2022] [Accepted: 09/10/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND A significant variation in RNA interference (RNAi) efficiency hinders further functional gene studies and pest control application in many insects. The available double-stranded RNA (dsRNA) molecules introduced into the target cells are regarded as the crucial factor for efficient RNAi response. However, numerous studies have only focused on dsRNA stability in vivo; it is uncertain whether different dsRNA storage conditions in vitro play a role in variable RNAi efficiency among insects. RESULTS A marker gene cardinal, which leads to white eyes when knocked-down in the red flour beetle Tribolium castaneum, was used to evaluate the effects of RNAi efficiency under different dsRNA storage conditions. We demonstrated that the dsRNA molecule is very stable under typical cryopreservation temperatures (-80 and -20 °C) within 180 days, and RNAi efficiency shows no significant differences under either low temperature. Unexpectedly, while dsRNA molecules were treated with multiple freeze-thaw cycles up to 50 times between -80/-20 °C and room temperature, we discovered that dsRNA integrity and RNAi efficiency were comparable with fresh dsRNA. Finally, when the stability of dsRNA was further measured under refrigerated storage conditions (4 °C), we surprisingly found that dsRNA is still stable within 180 days and can induce an efficient RNAi response as that of initial dsRNA. CONCLUSION Our results indicate that dsRNA is extraordinarily stable under various temperature storage conditions that did not significantly impact RNAi efficiency in vivo insects. © 2022 Society of Chemical Industry.
Collapse
Affiliation(s)
- Mei Bai
- State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, China
- Key Laboratory of Integrated Pest Management on the Loess Plateau of Ministry of Agriculture, College of Plant Protection, Northwest A&F University, Yangling, China
| | - Zi-Ling Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, China
- Key Laboratory of Integrated Pest Management on the Loess Plateau of Ministry of Agriculture, College of Plant Protection, Northwest A&F University, Yangling, China
| | - Yu-Yu Zhou
- State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, China
- Key Laboratory of Integrated Pest Management on the Loess Plateau of Ministry of Agriculture, College of Plant Protection, Northwest A&F University, Yangling, China
| | - Qiu-Xuan Xu
- State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, China
- Key Laboratory of Integrated Pest Management on the Loess Plateau of Ministry of Agriculture, College of Plant Protection, Northwest A&F University, Yangling, China
| | - Tong-Xian Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, China
- Key Laboratory of Integrated Pest Management on the Loess Plateau of Ministry of Agriculture, College of Plant Protection, Northwest A&F University, Yangling, China
| | - Hong-Gang Tian
- State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, China
- Key Laboratory of Integrated Pest Management on the Loess Plateau of Ministry of Agriculture, College of Plant Protection, Northwest A&F University, Yangling, China
| |
Collapse
|