• There are plenty of unanswered questions about the origin of life on Earth. • But the research community has largely reached consensus that one of the key steps was the emergence of an RNA molecule that could replicate itself. • RNA, like its more famous relative DNA, can carry genetic information. • But it can also fold up into three-dimensional structures that act as catalysts. • These two features have led to the suggestion that early life was protein-free, with RNA handling both heredity and catalyzing a simple metabolism. • For this to work, one of the reactions that the early RNAs would need to catalyze is the copying of RNA molecules, without which any sort of heritability would be impossible.
Article Summaries:
- There are plenty of unanswered questions about the origin of life on Earth. But the research community has largely reached consensus that one of the key steps was the emergence of an RNA molecule that could replicate itself. RNA, like its more famous relative DNA, can carry genetic information. But it can also fold up into three-dimensional structures that act as catalysts. These two features have led to the suggestion that early life was protein-free, with RNA handling both heredity and catalyzing a simple metabolism. For this to work, one of the reactions that the early RNAs would need to ca
- Scientists have discovered a 45‑base RNA molecule that can self‑replicate, a key milestone for theories of the RNA world. The short ribozyme, identified by a research team, functions as a polymerase, adding nucleotides one at a time to produce a copy of itself. Prior catalytic RNAs could copy other molecules but not self‑copy, leaving a gap in the proposed early life model where RNA handled both heredity and catalysis. This finding supports the idea that primitive life could have been protein‑free, with RNA alone managing replication and metabolic reactions.
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