Molecular Dynamics Simulations Reveal an Interplay between SHAPE Reagent Binding and RNA Flexibility

Area of Science:

• Biochemistry
• Molecular Biology
• Computational Biology

Background:

• RNA function is dictated by its complex three-dimensional fold and specific structural motifs.
• Chemical probing, particularly SHAPE, is vital for determining RNA secondary structure in vitro and in vivo.
• The precise structural determinants and reaction mechanisms underlying SHAPE reactivity remain incompletely understood.

Purpose of the Study:

• To elucidate the structural factors governing SHAPE reagent accessibility and reactivity.
• To investigate the role of local RNA conformations and nucleotide properties in SHAPE reactions.
• To predict SHAPE reactivity for nucleotide analogs and RNA structural motifs using computational methods.

Main Methods:

• Utilizing molecular dynamics (MD) simulations to model RNA behavior at the atomic level.
• Employing enhanced sampling techniques to explore diverse RNA conformational states.
• Predicting the accessibility of the 2'-hydroxyl group to SHAPE reagents based on simulated structures.

Main Results:

• Local RNA reconformations are essential for SHAPE reagents to access the 2'-hydroxyl group of nucleotides.
• The sugar pucker conformation of ribose is a significant determinant of SHAPE reactivity.
• Computational predictions align with experimental observations, validating the simulation approach.

Conclusions:

• SHAPE reactivity is highly sensitive to dynamic local structural rearrangements within RNA.
• Understanding sugar pucker dynamics is critical for accurate interpretation of SHAPE chemical probing data.
• Molecular dynamics simulations provide valuable insights into the mechanistic basis of SHAPE reactivity, aiding RNA structure determination.