RNA intrusions change DNA elastic properties and structure

Area of Science:

• Molecular Biology
• Biophysics
• Nanotechnology

Background:

• Ribonucleoside monophosphates (rNMPs) are the most common defects found in DNA.
• The impact of embedded rNMPs on DNA structure and mechanical properties remains largely uncharacterized.

Purpose of the Study:

• To investigate how rNMPs incorporated into DNA affect its structural and mechanical properties.
• To understand the implications of rNMP intrusions for DNA biological functions and nanotechnology applications.

Main Methods:

• Atomic force microscopy (AFM)-based single-molecule elasticity measurements.
• Molecular dynamics (MD) simulations.
• Nuclear magnetic resonance (NMR) spectroscopy.

Main Results:

• rNMP incorporation can decrease DNA stretch modulus by up to 32% or slightly increase it, depending on the DNA sequence.
• Significant local structural alterations in DNA were observed at and around rNMP sites.
• The nucleotide 3' to the rNMP site is particularly affected structurally.

Conclusions:

• rNMPs demonstrably alter the mechanical properties and local structure of DNA.
• These alterations may influence DNA's biological roles and have potential uses in DNA/RNA nanotechnology.