Naturally ornate RNA-only complexes revealed by cryo-EM

• 成果类型: Article
• 署名作者: Kretsch, Rachael C.; Wu, Yuan; Shabalina, Svetlana A.; Lee, Hyunbin; Nye, Grace; Koonin, Eugene V.; Gao, Alex; Chiu, Wah; Das, Rhiju
• 署名单位: Stanford University; Stanford University; Howard Hughes Medical Institute; National Institutes of Health (NIH) - USA; NIH National Library of Medicine (NLM); Division of Intramural Research (DIR); Stanford University; Stanford University; United States Department of Energy (DOE); SLAC National Accelerator Laboratory; Stanford University; Stanford University
• 刊物名称: Nature
• ISSN/ISSBN: 0028-1980
• DOI: 10.1038/s41586-025-09073-0
• 发表日期: 2025-07-24
• 关键词: secondary structure; noncoding rna; ole rna; refinement; genes; MODEL

摘要

The structures of natural RNAs remain poorly characterized and may hold numerous surprises1, 2, 3-4. Here we report three-dimensional structures of three large ornate bacterial RNAs using cryo-electron microscopy (cryo-EM). GOLLD (Giant, Ornate, Lake- and Lactobacillales-Derived), ROOL (Rumen-Originating, Ornate, Large) and OLE (Ornate Large Extremophilic) RNAs form homo-oligomeric complexes whose stoichiometries are retained at lower concentrations than measured in cells. OLE RNA forms a dimeric complex with long co-axial pipes spanning two monomers. Both GOLLD and ROOL form distinct RNA-only multimeric nanocages with diameters larger than the ribosome, each empty except for a disordered loop. Extensive intramolecular and intermolecular A-minor interactions, kissing loops, an unusual A-A helix and other interactions stabilize the three complexes. Sequence covariation analysis of these large RNAs reveals evolutionary conservation of intermolecular interactions, supporting the biological importance of large, ornate RNA quaternary structures that can assemble without any involvement of proteins.