2',5'-linked DNA is a template for polymerase-directed DNA synthesis

Area of Science:

• Biochemistry
• Molecular Biology
• Astrobiology

Background:

• Genomes naturally use 3",5 '-phosphodiester bonds in nucleic acids.
• The 2 ',5 '-phosphodiester linkage is a prevalent, nonenzymatic product of nucleotide oligomerization, suggesting a chemical bias.
• While 2 ',5 '-linked RNA exists naturally, it does not encode genetic information.

Purpose of the Study:

• To investigate the potential of 2 ',5 '-linked nucleic acids as genetic material.
• To explore the self-pairing and cross-pairing capabilities of 2 ',5 '-linked DNA and RNA with natural nucleic acids.
• To determine if 2 ',5 '-linked DNA can serve as a template for enzymatic synthesis of natural DNA.

Main Methods:

• Studied self-pairing and pairing with natural nucleic acids (DNA and RNA).
• Examined helix formation for 2 ',5 '-linked DNA and RNA.
• Tested 2 ',5 '-linked DNA as a template for DNA polymerases and reverse transcriptases.

Main Results:

• 2 ',5 '-linked DNA and RNA form stable helical structures with themselves.
• 2 ',5 '-linked nucleic acids show asymmetric pairing with natural nucleic acids (RNA but not DNA).
• 2 ',5 '-linked DNA functions as a template for enzymatic synthesis of natural DNA, incorporating all four nucleotides with high fidelity.

Conclusions:

• The 2 ',5 '-phosphodiester linkage has potential as an alternative genetic material, particularly in early life scenarios.
• Enzymatic processes can overcome structural limitations of non-natural nucleic acid linkages.
• 2 ',5 '-linked DNA's ability to template natural DNA synthesis has significant implications for origin-of-life studies and synthetic biology.