Repeats Influence Structural DNA Properties Around Functional Annotations Associated with 3D Organization and...

Area of Science:

• Genomics
• Epigenetics
• Molecular Biology

Background:

• The intricate relationship between chromatin 3D organization and transcriptional regulation remains incompletely understood.
• Growing evidence highlights the significant role of DNA repeats in influencing chromatin structure and function.
• DNA repeats affect local dinucleotide content, which in turn influences DNA structural properties and histone affinity.

Purpose of the Study:

• To investigate global correlations between transcriptional annotations, 3D organization, dinucleotide content, DNA properties, and DNA repeats in human and mouse genomes.
• To identify local variations in DNA properties around specific genomic annotations and assess the impact of dinucleotide and repeat content.

Main Methods:

• Performed genome-wide correlation analyses to link transcriptional annotations with 3D organization, DNA properties, and repeat elements.
• Analyzed local DNA property profiles around genomic annotations to determine the influence of dinucleotide composition and repeat types, including tandem repeats (TRs) and transposons.

Main Results:

• Identified robust associations between genomic annotations and DNA properties, modulated by various types of DNA repeats.
• Confirmed that the DNA structural property 'Roll' is particularly sensitive to the DNA sequence context.
• Demonstrated that repeat content significantly influences DNA properties.

Conclusions:

• DNA repeats exert a significant influence on DNA structural properties.
• These alterations in DNA properties indirectly affect histone occupancy.
• The findings suggest a novel indirect mechanism by which DNA repeats contribute to 3D chromatin organization.