Inverted Alu repeats in loop-out exon skipping across hominoid evolution

Area of Science:

• Genomics
• Evolutionary Biology
• Molecular Biology

Background:

• RNA splicing diversifies the human genome's functional landscape.
• Intronic Alu elements, when inverted, may form RNA stem-loop structures promoting exon skipping.

Purpose of the Study:

• To systematically analyze inverted Alu pairs in the human genome.
• To assess their impact on exon skipping and relevance to hominoid evolution.

Main Methods:

• Genome-wide analysis of inverted Alu pairs.
• Comparative genomic analysis across nine primate species.
• Experimental validation of specific Alu pairs.

Main Results:

• Inverted Alu pairs are enriched near skippable exons, particularly those with weak 3' splice sites.
• Identified 67,126 hominoid-specific Alu insertions forming inverted pairs.
• These pairs are enriched in ubiquitination pathway genes.

Conclusions:

• Inverted Alu pairs contribute to exon skipping via RNA secondary structures.
• Transposable elements, specifically Alu pairs, drive genomic innovation in hominoid evolution.