Complex genomic rearrangements lead to novel primate gene function

Area of Science:

• Evolutionary genomics
• Gene duplication and evolution
• Comparative genomics

Background:

• Single-copy orthologous genes across species suggest selection against duplication.
• Surviving gene duplicates may escape dosage control through functional changes.
• Understanding gene duplication mechanisms is key to identifying novel gene functions.

Purpose of the Study:

• To test the hypothesis that gene duplication of conserved single-copy genes leads to functional divergence.
• To develop a strategy for identifying novel gene functions through analysis of primate-specific duplications.
• To investigate the genomic rearrangements associated with the emergence of new gene families.

Main Methods:

• Analysis of 22 primate-specific intrachromosomal duplications of genes with single-copy orthologs in metazoans.
• Comparison of duplicated genes with those not under single-copy constraint.
• Detailed reconstruction of genomic events for a large duplication on human Chromosome 2, involving segmental duplications, inversions, translocations, exon loss, and domain accretion.

Main Results:

• Primate-specific duplications of single-copy genes show a higher tendency for gene structure modification via complex genomic rearrangements.
• A novel gene family of eight members evolved from the nucleoporin RanBP2 through multiple genetic rearrangements.
• Experimental verification confirmed altered cellular localization for a new protein and evidence of positive selection on specific domains.

Conclusions:

• Gene duplication of conserved single-copy genes in primates can drive the formation of novel gene families.
• Complex genomic rearrangements are crucial mechanisms in the evolution of these new gene families.
• Functional divergence and positive selection contribute to the evolutionary success of duplicated genes.