Evolutionary analysis reveals regulatory and functional landscape of coding and non-coding RNA editing

Area of Science:

• Molecular Biology
• Evolutionary Biology
• Neuroscience

Background:

• Adenosine-to-inosine (A-to-I) RNA editing diversifies the transcriptome, particularly in the brain.
• The mechanisms of RNA editing site selection, regulation, and functional importance remain largely unelucidated.

Purpose of the Study:

• To investigate the cis-regulation and evolutionary selection of RNA editing in Drosophila.
• To identify functionally important RNA editing sites in both coding and non-coding regions.

Main Methods:

• Comparative genomic analysis across Drosophila species.
• Evolutionary analyses to identify cis-regulatory elements controlling RNA editing.
• Functional characterization of editing sites in 3'UTRs.

Main Results:

• Cis-regulatory elements explain and predict RNA editing establishment and variation across Drosophila species.
• Early-evolved editing events are highly edited, clustered, and enriched in slowly-evolving neuronal genes, suggesting a role in fine-tuning neurological functions.
• Evolutionarily constrained 3'UTR editing sites impact mRNA stability and miRNA binding, highlighting the functional roles of noncoding RNA editing.

Conclusions:

• RNA editing regulation and function in Drosophila are shaped by evolutionary processes.
• Both coding and non-coding RNA editing sites play significant functional roles, particularly in neuronal gene regulation.
• This study provides novel insights into the evolutionary dynamics and functional significance of A-to-I RNA editing.