Structural basis for chaperone-guided assembly of RNA-induced silencing complex revealed
Researchers have determined the cryo-EM structure of the chaperone-assisted microRNA complex (AMC) with let-7a-1, revealing how molecular chaperones guide the assembly of the RNA-induced silencing complex (RISC). The study builds on decades of research into how Hsp70 and Hsp90 chaperones facilitate RISC formation across different organisms. This structural insight advances understanding of gene silencing mechanisms fundamental to RNA interference, with potential implications for therapeutic applications.
Scientists have elucidated the structural basis for how molecular chaperones direct the assembly of the RNA-induced silencing complex (RISC), a key component of the RNA interference pathway. Using cryo-EM, researchers determined high-resolution structures of the chaperone-assisted microRNA complex containing let-7a-1, with detailed maps of critical regions including the MID/PIWI domain, N-domain, and HSP90–p23 interactions. The work synthesizes findings from prior studies demonstrating that Hsp70 and Hsp90 chaperone machinery mediate ATP-dependent RISC loading in organisms ranging from plants to mammals. All structural data have been deposited in public databases (PDB and EMDB) with no access restrictions, enabling further research. This structural characterization clarifies fundamental steps in how small RNA duplexes are assembled into functional silencing complexes, a process central to gene regulation.
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Structural basis for chaperone-guided assembly of RNA-induced silencing complex
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