Publications by authors named "G Varani"

Flaviviruses, such as West Nile and Dengue Virus, pose a significant and growing threat to global health. Central to the flavivirus life cycle are highly structured 5'- and 3'-untranslated regions (UTRs), which harbor conserved cis-acting RNA elements critical for viral replication and host adaptation. Despite their essential roles, detailed molecular insights into these RNA elements have been limited.

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Noncoding RNAs, especially miRNAs, play a pivotal role in cancer initiation and metastasis, underscoring their susceptibility to precise modulation via small molecule inhibitors. This review examines the innovative strategy of targeting oncogenic miRNAs with small drug-like molecules, an approach that can reshape the cancer treatment landscape. We review the current understanding of the multifaceted roles of miRNAs in oncogenesis, highlighting emerging therapeutic paradigms that have the potential to expand cancer treatment options.

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Specificity of RNA-binding proteins for target sequences varies considerably. Yet, it is not understood how certain few proteins achieve markedly higher sequence specificity than most others. Here we show that the RNA Recognition Motif of RbFox accomplishes extraordinary sequence specificity by employing functionally and structurally distinct binding modes.

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We report the discovery of drug-like small molecules that bind specifically to the precursor of the oncogenic and pro-inflammatory microRNA-21 with mid-nanomolar affinity. The small molecules target a local structure at the Dicer cleavage site and induce distinctive structural changes in the RNA, which correlate with specific inhibition of miRNA processing. Structurally conservative single nucleotide substitutions eliminate the conformational change induced by the small molecules, which is also not observed in other miRNA precursors.

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Transcription of E-cadherin, a tumor suppressor that plays critical roles in cell adhesion and the epithelial-mesenchymal transition, is regulated by a promoter-associated non-coding RNA (paRNA). The sense-oriented paRNA (S-paRNA) includes a functional C/A single nucleotide polymorphism (SNP rs16260). The A-allele leads to decreased transcriptional activity and increased prostate cancer risk.

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