Protein kinase C family evolution in jawed vertebrates

Area of Science:

• Evolutionary biology
• Genomics
• Molecular biology

Background:

• Protein Kinase C (PKC) is a family of kinases involved in crucial cellular functions like cell cycle regulation and immune response.
• In mammals, 12 PKC genes are known, typically classified into 4 subfamilies.
• Understanding the evolutionary history of PKC genes is vital for comprehending vertebrate evolution.

Purpose of the Study:

• To conduct a comprehensive evolutionary analysis of PKC genes in jawed vertebrates.
• To investigate the impact of whole-genome duplication events (1R, 2R, and 3R) on the PKC gene family.
• To propose an updated classification of the PKC family based on evolutionary findings.

Main Methods:

• Synteny analysis
• Paralogon analysis
• Comparative genomics of PKC genes across jawed vertebrates and related species (tunicates, lancelets).

Main Results:

• The vertebrate ancestor likely possessed five PKC genes, consistent with tunicates and lancelets.
• Two early genome duplication events (1R and 2R) resulted in 12 PKC genes in jawed vertebrates.
• A subsequent teleost-specific genome duplication (3R) increased the gene count to 21 in teleosts, with zebrafish retaining 19.
• No independent gene duplications were identified; all complexity arises from genome doublings.

Conclusions:

• The PKC gene family's expansion and complexity in jawed vertebrates are solely attributable to ancient whole-genome duplication events.
• An evolutionary perspective suggests organizing the PKC family into five subfamilies.
• These genome doublings significantly impacted vertebrate evolution.