Plant diseases and insect pests threaten the safety of crop production greatly. Traditional methods for pest management are challenged by the problems such as environmental pollution, off-target effects, and resistance of pathogens and insects. New biotechnology-based strategies for pest control are expected to be developed. RNA interference (RNAi) is an endogenous process of gene regulation, which has been widely used to study the gene functions in various organisms. In recent years, RNAi-based pest management has received increasing attention. The effective delivery of the exogenous interference RNA into the targets is a key step in RNAi-mediated plant diseases and pest control. Considerable advances were made on the mechanism of RNAi, and various RNA delivery systems were developed for efficient pest control. Here we review the latest advances on mechanisms and influencing factors of RNA delivery, summarize the strategies of exogenous RNA delivery in RNAi-mediated pest control, and highlight the advantages of nanoparticle complexes in dsRNA delivery.
Animals ; RNA Interference ; Pest Control ; Insecta/genetics* ; RNA, Double-Stranded ; Gene Expression Regulation

As the discovery of RNA interference (RNAi) and the gradual conquering of a series of technical issues, a few of RNAi therapeutics have been approved in the non-tumor field abroad. With the advantages of high specificity, long duration of efficacy, and high success rate of development, RNAi therapeutics have become the emerging field globally. There are no RNAi therapeutics approved in oncology so far, and people are hoping a breakthrough in the field. In the present article, the characteristics and potential anti-tumor mechanism of RNAi therapeutics, difficulties in delivery system and progress in oncology are described, and the potential reasons why their success in non-tumor field is difficult to be simply replicated in tumor field are analyzed, providing reference for research and clinical transformation of RNAi therapeutics in oncology.
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Humans ; Lung Neoplasms/genetics* ; RNA Interference ; RNA, Small Interfering/therapeutic use*

RNA interference (RNAi) is one of the important mechanisms to regulate gene expression in eukaryotes. One of the original functions of RNAi is to facilitate the antiviral strategy of host. Early studies reveal that invertebrates can use RNAi to resist viruses. However, if this mechanism exists in mammals is still controversial. The latest studies confirm that mammals do have the RNAi-based immunity, and researchers believe that RNAi-based antiviral immunity is a brand-new immunological mechanism that was neglected in the past. It is worthy to note that virus can also use RNAi to enhance its infectivity and immune escape in host cells. This review introduces the research history of RNAi-based antiviral immunity in animals and summarizes the main findings in this field. Last but not least, we indicate a series of unresolved questions about RNAi-based antiviral immunity, and explore the relationship between RNAi-based antiviral immunity and other innate immunological pathways. The virus-mediated RNAi pathway in animal is not only an interesting basic biology question, but also has important guiding roles in the development of antiviral drugs.
Animals ; Antiviral Agents ; Immunity, Innate/genetics* ; Mammals ; RNA Interference ; RNA, Small Interfering/genetics* ; RNA, Viral

This study cloned the transcription factor gene PnbHLH which held an open reading frame of 966 bp encoding 321 amino acids. This study constructed the overexpression vector of transcription factor PnbHLH of Panax notoginseng. The combination of PnbHLH overexpression and RNAi of the key enzyme gene PnCAS involved in the phytosterol biosynthesis was achieved in P. notoginseng cells, thus exploring the biosynthetic regulation of P. notoginseng saponins(PNS) by the synergistic effect of PnbHLH overexpression and PnCAS RNAi. The results showed that the PnbHLH transcription factor interacted with the promoters of key enzyme genes PnDS, PnSS and PnSE in the biosynthetic pathway of PNS, and then regulated the expression levels of key enzyme genes and affected the biosynthesis of saponins indirectly. Further study indicated that the synergistic effect of PnbHLH overexpression and PnCAS RNAi was a more effective approach to regulate the biosynthesis of saponins. Compared with the wild type and PnCAS RNAi cells of P. notoginseng, the contents of total saponins and monomeric saponins(Rd, Rb_1, Re, Rg_1 and R_1) were increased to some extent in the cell lines of PnbHLH overexpression and PnCAS RNAi. This indicated that the two ways of forward regulation and reverse regulation of saponin biosynthesis showed superposition effect. This study explored a more rational and efficient regulation strategy of PNS biosynthesis based on the advantages of multi-point regulation of transcription factors as well as the down-regulation of by-product synthesis of saponins.
Intramolecular Transferases ; Panax notoginseng ; RNA Interference ; Saponins ; Transcription Factors/genetics*

In this study, based on the transcriptome database of suspension cells of Arnebia euchroma, we explored two candidate cytochrome P450 enzyme genes that might relate to the shikonin biosynthesis downstream pathway when CYP76B74 sequence was referenced. We constructed interference-type hairy roots of candidate genes and cultured them. We measured the fresh weight, dry weight, total naphthoquinone content, shikonin and its derivatives content and expression levels of key enzyme genes involved in shikonin biosynthesis pathway. The effects of candidate genes on the growth and shikonin production of A. euchroma hairy roots were discussed, and the possible regulatory mechanisms that candidate genes affected shikonin synthesis were discussed. Through local Blast and phylogenetic analysis, two candidate CYP450 genes(CYP76B75 and CYP76B100) with high homology to CYP76B74 in A. euchroma were screened, and corresponding interference hairy roots were constructed. Compared with the control(RNAi-control), the fresh weight of CYP76B75 interfered hairy root(RNAi-CYP76B75) and CYP76B100 interfered hairy root(RNAi-CYP76B100) were significantly reduced, while dry weight were not affected, so the dry rate increased significantly. Except for β-acetoxyisovalerylalkannin, which is high in three groups of hairy roots, the contents of shikonin, deoxyshikonin, acetylshikonin, β,β'-dimethacrylicalkannin, β-hydroxyisovalerylshikonin,β-hydroxyisovalerylshikonin, isobutyrylshikonin and total naphthoquinones showed a consistent pattern: RNAi-CYP76B75>RNAi-CYP76B100>RNAi-control. Among them, the synthesis of β-hydroxyisovalerylshikonin was most significantly promoted by interfering with the expression of CYP76B75. The content of β-hydroxyisovalerylshikonin in RNAi-CYP76B75 was 11.7 times that of RNAi-control. RESULTS:: of real-time qPCR analysis showed that compared to RNAi-control, the expression levels of AePGT gene in RNAi-CYP76B75 and RNAi-CYP76B100 were not changed significantly, and the expression levels of CYP76B74 and AeHMGR were up-regulated. In addition, the expression level of CYP76B100 in RNAi-CYP76B75 was down-regulated, whereas in RNAi-CYP76B100, the expression of CYP76B75 was significantly up-regulated. Therefore, this study confirmed that when the expression of CYP76B75 and CYP76B100 were interrupted, the growth of hairy roots were suppressed, but the synthesis of shikonin were promoted. They might increase the shikonin biosynthesis by up-regulating the expression of CYP76B74 in the hairy roots of A. euchroma.
Boraginaceae ; genetics ; Cytochrome P-450 Enzyme System ; Naphthoquinones ; Phylogeny ; Plant Roots ; RNA ; RNA Interference

Objective To discover critical genes contributing to the stemness and maintenance of spermatogonial stem cells (SSCs) and provide new insights into the function of the leucine-rich repeat (LRR) family member Lrrc34 (leucine-rich repeat-containing 34) in SSCs from mice. Methods Bioinformatic methods, including differentially expressed gene (DEG), gene ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses, were used to uncover latent pluripotency-related genes. Reverse transcription-polymerase chain reaction (RT-PCR) and immunofluorescence analyses were utilized to verify the mRNA and protein expression levels, respectively. RNA interference of Lrrc34 using siRNA was performed to detect its transient impact on SSCs. Results Eight DEGs between ID4-EGFP⁺ (G) and ID4-EGFP⁺/TSPAN8^High (TH), eight DEGs between G and ID4-EGFP⁺/TSPAN8^Low (TL) and eleven DEGs between TH and TL were discovered, and eleven protein-protein interaction (PPI) modules were found to be significant in the PPI network of DEGs. One of the DEGs, Lrrc34, was selected as a potential pluripotency-related gene due to its differential expression among ID4-EGFP⁺ spermatogonia subsets and its interaction with fibroblast growth factor 2 in the fifth module. Immunofluorescence experiments exhibited specific expression of Lrrc34 in a subpopulation of undifferentiated spermatogonia marked by LIN28A, and RT-PCR experiments confirmed the high expression of Lrrc34 in SSCs from P7 and adult mice. The transient knockdown of Lrrc34 in SSCs resulted in reduced colony sizes and significant changes in the transcriptome and apoptotic pathways. Conclusion Lrrc34 is highly expressed in mouse SSCs and is required for SSC proliferation in vitro through effects on transcriptome and signaling transduction pathways.
Animals ; Apoptosis/genetics* ; Cell Proliferation/genetics* ; Cells, Cultured ; Gene Expression Profiling/methods* ; Gene Ontology ; Gene Regulatory Networks ; Humans ; Male ; Mice, Inbred C57BL ; Mice, Transgenic ; RNA Interference ; Repressor Proteins/metabolism* ; Signal Transduction/genetics* ; Stem Cells/metabolism*

Suppressor of Variegation 3–9 Homolog 2 (SUV39H2) methylates the lysine 9 residue of histone H3 and induces heterochromatin formation, resulting in transcriptional repression or silencing of target genes. SUV39H1 and SUV39H2 have a role in embryonic development, and SUV39H1 was shown to suppress cell cycle progression associated with Rb. However, the function of human SUV39H2 has not been extensively studied. We observed that forced expression of SUV39H2 decreased cell proliferation by inducing G1 cell cycle arrest. In addition, SUV39H2 was degraded through the ubiquitin-proteasomal pathway. Using yeast two-hybrid screening to address the degradation mechanism and function of SUV39H2, we identified translationally controlled tumor protein (TCTP) as an SUV39H2-interacting molecule. Mapping of the interacting regions indicated that the N-terminal 60 amino acids (aa) of full-length SUV39H2 and the C-terminus of TCTP (120–172 aa) were critical for binding. The interaction of SUV39H2 and TCTP was further confirmed by co-immunoprecipitation and immunofluorescence staining for colocalization. Moreover, depletion of TCTP by RNAi led to up-regulation of SUV39H2 protein, while TCTP overexpression reduced SUV39H2 protein level. The half-life of SUV39H2 protein was significantly extended upon TCTP depletion. These results clearly indicate that TCTP negatively regulates the expression of SUV39H2 post-translationally. Furthermore, SUV39H2 induced apoptotic cell death in TCTP-knockdown cells. Taken together, we identified SUV39H2, as a novel target protein of TCTP and demonstrated that SUV39H2 regulates cell proliferation of lung cancer cells.
Amino Acids ; Apoptosis ; Carrier Proteins ; Cell Cycle ; Cell Death ; Cell Proliferation ; Embryonic Development ; Female ; Fluorescent Antibody Technique ; G1 Phase Cell Cycle Checkpoints ; Half-Life ; Heterochromatin ; Histones ; Humans ; Immunoprecipitation ; Lung Neoplasms ; Lysine ; Mass Screening ; Pregnancy ; Repression, Psychology ; RNA Interference ; Up-Regulation ; Yeasts

OBJECTIVE: This study aimed to explore the influence of Rce1 on invasion and migration of tongue squamous cell carcinoma cells by silencing the Rce1 gene with RNA interference. METHODS: The tongue squamous cell carcinoma Cal-27 and SCC-4 cells were cultured in vitro. The small interfering RNA (siRNA) of the Rce1 gene was designed, and the Rcel gene expression was silenced vialiposome transfection. According to the siRNA transfected by liposome, the experimental group was divided into three groups, namely, Rce1-siRNA-1, Rce1-siRNA-2, and Rce1-siRNA-3 groups. Negative control group was transfected by siCON, and the blank control group was untransfected by siRNA. The Rce1, RhoA, and K-Ras gene expression levels in each group were analyzed by real-time quantitative polymerase chain reaction. The Rce1, RhoA, K-Ras, MMP-2, and MMP-9 protein expression levels were analyzed by Western blot. The invasiveness of tongue cancer cell Cal-27 and SCC-4 were determined by Transwell invasion assay, and cell migration assay was performed by cell scratch assay. RESULTS: Real-time quantitative polymerase chain reaction and Western blot results showed that compared with the negative and blank control groups, the Rce1 gene and protein expression levels in three experimental groups decreased (P<0.05). The RhoA, K-Ras gene and protein expression levels were insignificantly different among groups (P>0.05). Meanwhile, the MMP-2 and MMP-9 expression levels decreased (P<0.05). Transwell invasion assay results showed that the total number of cells in the PET film of the experimental groups was significantly decreased compared with the control group (P<0.05). The cell scratch test showed that the cell closure time of the scratch in the interference group was significantly longer than those in the control and blank groups (P<0.05). CONCLUSIONS Silencing Rce1 in vitro can effectively downregulate its expression in tongue squamous cell carcinoma cells Cal-27 and SCC-4 and reduce the migration and invasion abilities of these cells.
Cell Line, Tumor ; Cell Movement ; Cell Proliferation ; Endopeptidases ; metabolism ; Humans ; Neoplasm Invasiveness ; RNA Interference ; RNA, Small Interfering ; Tongue Neoplasms ; metabolism ; therapy ; Transfection

OBJECTIVE: To investigate the effect of steadily down-regulating the expression of calreticulin (CALR) on the invasion of natural killer/T-cell lymphoma SNK6 cells, and explore its possible mechanism. METHODS: The sequences of specific short hairpin RNA (shRNA) targeting on human CALR were designed, and were inserted into pLKO.1-puro lentivirus vector, and the reconbinant lentivirus vector was obtained; the lentivirus particles were backed by three-plasmid system and transfected into SNK6 cells, the SNK6 cells stably down-regulating the CALR expression were sercened by puromytain, the CALR-silencing effect was verified by real-time PCR and Western blot. CCK-8 assay was used to evaluate the cell viability, The transwell invasion assays was used to analyse invasion of SNK6 cells. The mRNA expression of Calreticulin, MMP2, MMP9 and VEGF was determined by real time PCR, the protein expression of Calreticulin and GAPDH was analyzed by Western blot. RESULTS: The recombinant lentiviral vector pLKO.1-puro-shCALR was successfully constructed, packed into the lentivirus, then the SNK6 cells stably down-regulating Calreticulin expression was obtained. When Calreticulin was down-rengulated in SNK6 cells, the proliferation rate was reduced and the invasion ability was decreased; the mRNA levels of VEGF and MMP-2/9 also were reduced. CONCLUSION The stable down-regnlation of CALR expression in SNK6 cells can attenuate the imvasiveness of SNK6 cells, which maybe related with transcriptional decrease of MMP2, MMP9 and VEGF.
Calreticulin ; genetics ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; Down-Regulation ; Genetic Vectors ; Humans ; Lentivirus ; Matrix Metalloproteinase 2 ; Matrix Metalloproteinase 9 ; RNA Interference ; RNA, Small Interfering ; Transfection ; Vascular Endothelial Growth Factor A

OBJECTIVE: To analyze the effect of down-regulating the CD59 gene expression by RNAi lentivirus as vector on Jurkat cell line of acute T-lineage leukemia. METHODS: The expression of CD59 in Jurkat cell line of acute T-line leukemia was induced to decrease by RNAi lentivirus as vector. The transfection of RNA lentivirus and the localization of CD59 molecule were analyzed by laser confocal technique. The relative expression of CD59 gene in blank control, negative control and RNAi lentivirus transfected group was detected by real-time fluorescence quantitative PCR, and the enzyme-linked immunosorbent assay was used to detect the expression of TNF-β and IL-3 in supernatants of cultured cells in 3 groups. The expression levels of apoptosis-related molecules including Caspase-3, Survivin, BCL-2 and BCL-2-associated X protein (BAX) were measured by Western blot. RESULTS: The transfection efficiency for Jurkat cells was higher than 90%. CD59 was mainly located on the cell membrane. Compared with the blank control group and the negative control group, the expression level of CD59 mRNA and protein in the RNAi lentivirus transfected group significantly decreased (P<0.05). Compared with the blank control group and the negative control group, the expression of TNF-β and IL-3 in the RNAi lentivirus transfected group were significantly higher and lower (P<0.05) respectively. The expression levels of Survivin and BCL-2 in the RNAi lentivirus transfected group were significantly lower than those in the blank control group and the negative control group, while the expression levels of Caspase-3 and BAX in the RNAi lentivirus transfected group were significantly higher than those in the blank control group and the negative control group (P< 0.05). CONCLUSION The down-regulation of CD59 gene expression induced by RNAi lenti-virus can decrease the expression of proliferation and differentiation-promoting molecule such as IL-3 and increase the expression of TNF-related factor in Jurkat cell line of acute T-lineage leukemia, which also can increase the expression of apoptosis-related proteins such as Caspase-3 and BAX, and decrease the expression of anti-apoptosis-related proteins such as Survivin and BCL-2.
Apoptosis ; CD59 Antigens ; Cell Lineage ; Cell Proliferation ; Down-Regulation ; Humans ; Jurkat Cells ; Lentivirus ; Leukemia ; RNA Interference ; RNA, Small Interfering ; Transfection