Gene Regulatory Evolution During Speciation in a Songbird.

Area of Science:

• Evolutionary biology
• Genomics
• Speciation

Background:

• Comparative genomics has advanced gene regulatory evolution understanding.
• Bird gene regulation and hybrid interactions remain understudied.
• Avian unique features (female heterogamety, conserved karyotype) are key to speciation research.

Purpose of the Study:

• Investigate gene regulatory evolution in zebra finch subspecies.
• Analyze gene expression divergence in parental populations and F1 hybrids.
• Determine patterns of cis- and trans-regulatory divergence in birds.

Main Methods:

• Utilized replicated RNA-sequencing (RNA-seq) libraries.
• Analyzed brain gene expression divergence between zebra finch subspecies.
• Compared gene expression in parental lines and their F1 hybrids.

Main Results:

• Significant brain gene expression divergence observed between zebra finch subspecies.
• Gene misexpression is rare in brain-expressed transcripts of male hybrids.
• Most regulatory divergence occurs in cis, not trans, contrary to expectations.

Conclusions:

• Avian regulatory evolution exhibits both unique and shared characteristics with other taxa.
• Limited gene misexpression in hybrids may contribute to slow reproductive isolation in birds.
• Cis-regulatory divergence is prevalent in avian speciation, similar to other species.