Inside the RNA world, 40 years on

Area of Science:

• Origin of Life Studies
• Systems Chemistry
• Molecular Evolution

Background:

• The RNA world hypothesis proposes RNA preceded DNA and proteins.
• Early objections centered on RNA's chemical instability and replication challenges.

Purpose of the Study:

• Reframe the RNA world hypothesis as an RNA-centered evolutionary phase.
• Address long-standing objections using systems chemistry and ribozyme research.
• Investigate the role of peptides in early RNA-based systems.

Main Methods:

• Systems chemistry experiments on nucleotide activation and template copying.
• Analysis of wet-dry and freeze-thaw cycles on RNA polymerization.
• Investigating compartment effects on RNA retention and parasite control.
• Characterizing polymerase ribozymes for structure, processivity, and fidelity.
• Studying peptide-RNA interactions, including ligation and synthesis.

Main Results:

• Experimental constraints now address RNA activation, copying, and environmental influences.
• Polymerase ribozymes demonstrate sustained RNA-catalyzed evolution.
• Evidence supports ribonucleoprotein models with coevolving peptides and RNA.
• Peptide integration with RNA is shown through various chemical pathways.

Conclusions:

• The RNA world is better understood as an RNA-centered phase, integrating peptides.
• Systems chemistry and ribozyme studies provide testable benchmarks for RNA-centered evolution.
• Further research on chemically heterogeneous systems is needed to resolve remaining bottlenecks.