Tag

Ribozyme

All articles tagged with #ribozyme

science1 month ago•48 min saved

3′-Phosphate–Dependent Ribozyme Ligases Hint at RNA-Repair Pathways in Early Life

Researchers discovered four classes of ribozyme ligases that catalyze a novel ligation: the substrate’s 2′-OH attacks the ribozyme’s own 5′-triphosphate only when the substrate bears a neighboring 3′-phosphate, producing a 2′–5′ phosphodiester bond. These ligases show strict dependence on a 3′-phosphate and can ligate even without an external template (for at least one variant), with Mg2+ likely helping localize catalytic ions. In addition to revealing a new RNA-catalysis mode, the authors demonstrate selective capture and amplification of 3′-phosphorylated RNAs from mixed cellular RNA, offering a potential transcriptomics reagent to profile RNA cleavage products. The work also provides a plausible, salvage-like RNA repair mechanism in the RNA World and highlights how a single selection pressure can yield multiple related ribozymes with shared structural features.

via Nature|

#3-phosphate #ribozyme #rna-ligase

science4 months ago•4 min saved

A Tiny RNA Enzyme Edges the RNA World Toward Self-Replication

Researchers report QT45, a small polymerase ribozyme that can copy its own RNA and its template, demonstrating two crucial steps toward self-replication and bolstering the RNA world hypothesis; while not yet fully self-replicating, QT45 is smaller and more plausible to arise in prebiotic conditions than earlier ribozymes, discovered by screening trillions of random RNAs under cold conditions, with next steps to improve speed and yield.

via ScienceAlert|

#origin-of-life #qt45 #ribozyme

science6 months ago•9 min saved

Tiny 45-base ribozyme copies itself, nudging origin-of-life theories

Researchers identified QT-45, a 45-base RNA ribozyme that can act like a tiny polymerase to copy RNA strands and, crucially, can synthesize a copy of its own sequence by base-pairing with a template. In tests, QT-45 copied various RNAs with about 95% fidelity (roughly 2–3 errors per copy), though the process is slow. This demonstrates self-replicating RNA is plausible at very small sizes and could be refined by evolution under prebiotic conditions.

via Ars Technica|

#origin-of-life #polymerase #ribozyme

science6 months ago•15 min saved

RNA World Revisited: How RNA Catalysis Might Have Sparked Life

Explores the RNA world hypothesis, showing how RNA catalysis and ribozymes—and a ribosomal RNA core—support an RNA-first origin of life, while outlining prebiotic pathways from simple molecules like hydrogen cyanide and noting competing ideas such as amyloid scaffolds and the ongoing uncertainty about proving the theory.

via Chemistry World|

#abiogenesis #protocells #ribosome

science2 years ago•2 min saved

"RNA: The Key to Life's Origins on Earth"

Researchers have discovered a ribozyme that could have facilitated the emergence of RNA-based life on Earth, shedding light on the potential origins of life and the transition from simple molecules to complex organisms. This finding supports the RNA World hypothesis, which suggests that RNA played a crucial role in kickstarting Earth's biology without the involvement of DNA or proteins. The team's experiment demonstrated a higher-fidelity RNA polymerase ribozyme that produced RNA strands with greater accuracy, offering insights into the early stages of evolution and the possibility of autonomous RNA replication in the near future.

via Gizmodo|

#evolution #origin-of-life #ribozyme