Emergent Chemical Reactivity and Complexity of RNA Condensates.

Area of Science:

• Origin of Life Studies
• Biochemistry
• Molecular Biology

Background:

• The RNA world hypothesis suggests early life was RNA-based, but key aspects like catalysis and compartmentalization remain unclear.
• RNA's stability, catalytic abilities, and ability to concentrate reactants are critical for understanding its role in abiogenesis.

Purpose of the Study:

• To investigate the role of RNA phase separation in the context of the RNA world hypothesis.
• To explore the catalytic and compartmentalizing capabilities of RNA condensates under prebiotic conditions.

Main Methods:

• Studying the phase separation behavior of short RNAs at acidic pH.
• Analyzing the composition and stability of the resulting RNA condensates.
• Assessing the catalytic activity and reactant concentration within these condensates.

Main Results:

• Short RNAs (approx. 20 nt) at acidic pH form condensed phases enriched with long RNA.
• These RNA condensates stably compartmentalize RNA, DNA, and other molecules like peptides and proteins, without membranes.
• Condensates act as microreactors, concentrating reactants and exhibiting inherent catalytic activity, supporting ribozyme and enzyme function.

Conclusions:

• RNA phase separation provides a mechanism for compartmentalization and molecular enrichment relevant to the origin of life.
• RNA condensates possess dual catalytic functions: physical concentration of reactants and direct chemical catalysis.
• These findings highlight RNA phase separation as a significant factor in the emergence of early life, offering stability and catalytic potential.