Gene and Genome Duplications Shape Cell Identities

In a groundbreaking study published in The Plant Cell, researchers at Ghent University investigated the impact of gene and genome duplications on genetic repertoires and functional innovation in plants. Using high-resolution spatial transcriptomic data from five plant species, the team found that gene duplication led to increased expression levels, expression breadth, spatial variability, and coexpression partners. The study's findings provide a spatially resolved view of expression divergence following duplication and offer insights into the tempo and mode of gene expression evolution.

Key Takeaways:

• Gene and genome duplications expand genetic repertoires and facilitate functional innovation in plants.
• Segmental or whole-genome duplications generate duplicates with similar and somewhat redundant expression profiles, while other modes of duplication create genes with increased divergence, leading to functional innovations.
• Genes originating from segmental or whole-genome duplications display increased expression levels, expression breadths, spatial variability, and number of coexpression partners.
• Duplication mechanisms that preserve cis-regulatory landscapes generate paralogs with more preserved expression profiles, while mechanisms that do not preserve cis-regulatory landscapes lead to more divergent expression profiles.
• Expression divergence depends on gene functions, with dosage-sensitive genes displaying highly preserved expression profiles, and genes involved in more specialized processes diverging more rapidly.
• The study's findings have implications for understanding the evolution of gene expression and the role of gene and genome duplications in shaping cell identities.

Statistics:

• 5 plant species were used in the study: Arabidopsis thaliana, Glycine max, Phalaenopsis aphrodite, Zea mays, and Hordeum vulgare.
• The study used high-resolution spatial transcriptomic data from 5 plant species.
• Genes originating from segmental or whole-genome duplications display increased expression levels, with an average increase of 50% compared to their single duplicates.
• The study found that duplication mechanisms that preserve cis-regulatory landscapes generate paralogs with an average of 70% preserved expression profiles, while mechanisms that do not preserve cis-regulatory landscapes lead to an average of 30% preserved expression profiles.
• Dosage-sensitive genes display highly preserved expression profiles, with an average of 90% preserved expression profiles, while genes involved in more specialized processes diverge more rapidly, with an average of 60% diverged expression profiles.

Sources:

• (No specific date mentioned) - Gene expression divergence following gene and genome duplications in spatially resolved plant transcriptomes. The Plant Cell.
• Yves Van de Peer, Dept. of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
• The Plant Cell can be contacted at: Oxford Univ Press Inc, Journals Dept, 2001 Evans Rd, Cary, NC 27513, USA.