While microRNAs (miRNAs) are recognized as playing a critical role in regulating eukaryotic gene expression, both the mechanism by which these small, noncoding RNAs function and the genes they target remain elusive. Previous studies have shown that short, single-stranded 2'-O-methyl-modified oligonucleotides that are complementary to mature microRNA sequences can interact with the miRNA-RISC nucleoprotein complex and weakly inhibit miRNA function. Here we report the identification of secondary structural elements that enhance the potency of these molecules. Incorporation of highly structured, double-stranded flanking regions around the reverse complement core significantly increases inhibitor function and allows for multi-miRNA inhibition at subnanomolar concentrations. The improved functionality of these double-stranded miRNA inhibitors may provide insights into the miRNA mechanism by suggesting the possible importance of such structures in or near endogenous miRNA target sites.
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http://dx.doi.org/10.1261/rna.448107 | DOI Listing |
Nat Commun
January 2025
Department of Physics and Astronomy, Michigan State University, East Lansing, MI, USA.
DEAD-box RNA-dependent ATPases are ubiquitous in all domains of life where they bind and remodel RNA and RNA-protein complexes. DEAD-box ATPases with helicase activity unwind RNA duplexes by local opening of helical regions without directional movement through the duplexes and some of these enzymes, including Ded1p from Saccharomyces cerevisiae, oligomerize to effectively unwind RNA duplexes. Whether and how DEAD-box helicases coordinate oligomerization and unwinding is not known and it is unclear how many base pairs are actively opened.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Guizhou Provincial Key Laboratory for Agricultural Pest Management of Mountainous Regions, Institute of Entomology, Guizhou University, Guiyang, Guizhou 550025, China. Electronic address:
RNA interference (RNAi) is a promising method for pest control; however, some studies have showed that the degradation of double-stranded RNA (dsRNA) by dsRNA-degrading nucleases (dsRNases) is one of the factors that may reduce RNAi efficiency in lepidopteran insects. In this study, we cloned two dsRNase genes named CmdsRNase5 and CmdsRNase6 from rice leaffolder Cnaphalocrocis medinalis, a notorious insect pest of rice. Open reading frames (ORFs) of CmdsRNase5 and CmdsRNase6 are 1317 and 1185 bp in length, encoding 438 and 394 amino acids, respectively.
View Article and Find Full Text PDFBiosens Bioelectron
January 2025
Education Department of Guangxi Zhuang Autonomous Region, Laboratory of Optic-electric Chemo/Biosensing and Molecular Recognition, Guangxi Collaborative Innovation Center for Chemistry and Engineering of Forest Products, Guangxi Key Laboratory of Chemistry and Engineering of Forest Products, Key Laboratory of Chemistry and Engineering of Forest Products, State Ethnic Affairs Commission, School of Chemistry and Chemical Engineering, Guangxi Minzu University, Nanning 530006, China. Electronic address:
Sugarcane smut is a widespread fungal disease, which severely impairs the quality and sugar yield of sugarcane. Early detection is crucial for mitigating its impact, which makes the development of a highly sensitive and accurate detection method essential. Herein, the Mn-doped zeolite imidazolate framework (ZIF-67), synthesized via a nano-confined-reactor approach, is designed to significantly enhance electron transport and boost the enzyme loading capacity within biofuel cells, thereby potentially enhancing their overall performance.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
Department of Immunology and Microbiology, Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong 510000, China.
The LIM-domain-only protein LMO2 interacts with LDB1 in context-dependent multiprotein complexes and plays key roles in erythropoiesis and T cell leukemogenesis, but whether they have any roles in B cells is unclear. Through a CRISPR/Cas9-based loss-of-function screening, we identified LMO2 and LDB1 as factors for class switch recombination (CSR) in murine B cells. LMO2 contributes to CSR at least in part by promoting end joining of DNA double-strand breaks (DSBs) and inhibiting end resection.
View Article and Find Full Text PDFNature
January 2025
Frontiers Medical Center, Tianfu Jincheng Laboratory, Chengdu, China.
Identifying phase-separated structures remains challenging, and effective intervention methods are currently lacking. Here we screened for phase-separated proteins in breast tumour cells and identified forkhead (FKH) box protein M1 (FOXM1) as the most prominent candidate. Oncogenic FOXM1 underwent liquid-liquid phase separation (LLPS) with FKH consensus DNA element, and compartmentalized the transcription apparatus in the nucleus, thereby sustaining chromatin accessibility and super-enhancer landscapes crucial for tumour metastatic outgrowth.
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