An evolutionary driver of interspersed segmental duplications in primates

Area of Science:

• Genomics
• Evolutionary Biology
• Primate Genetics

Background:

• Segmental duplications contribute to genomic rearrangements and neurodevelopmental diseases.
• Low-complexity regions (LCRs) are implicated in driving these duplications.
• LCR16a is a key LCR encoding the rapidly evolving nuclear pore interacting protein (NPIP) gene family.

Purpose of the Study:

• To investigate the evolutionary history of LCR16a.
• To understand its role in the expansion of the NPIP gene family.
• To explore the impact on primate evolution and gene function.

Main Methods:

• Comparative genomic analysis across primate lineages.
• Analysis of gene structure and expression patterns.
• Mouse transgenic experiments to assess functional impacts.

Main Results:

• LCR16a independently expanded in five primate lineages over 35 million years.
• Expansions led to lineage-specific segmental duplications and novel gene structures.
• NPIP gene family showed altered expression in African apes, driven by cis-acting mutations, and signatures of positive selection.

Conclusions:

• LCR16a promotes interspersed duplications and genomic instability in primates.
• Significant changes in NPIP gene structure and expression preceded adaptive evolution in African apes.
• LCR16a is a driver of genomic and evolutionary innovation in primate genomes.