Frequent birth-and-death events throughout perforin-1 evolution

Area of Science:

• Genomics
• Evolutionary Biology
• Immunology

Background:

• Perforin-1 is crucial for the immune system by creating pores in cell membranes.
• The perforin gene has undergone complex evolutionary events like amplification and pseudogenization.
• Recent genomic data has enabled detailed annotation of perforin-1 homologs across many species.

Purpose of the Study:

• To annotate perforin-1 homologs in over eighty species.
• To investigate the evolutionary history and patterns of the perforin gene.
• To understand the diversity of perforin gene structures and copy numbers across vertebrate classes.

Main Methods:

• Assisted annotation of new genomic assemblies.
• Comparative genomics analysis of perforin-1 homologs.
• Identification and characterization of perforin gene loci and pseudogenes.

Main Results:

• Over 400 perforin genes were annotated across mammals, reptiles, birds, amphibians, and fishes.
• Mammals typically have one perforin locus, with some showing gene expansions.
• Reptiles and fish exhibit multiple perforin loci with varying copy numbers and exon/intron structures.

Conclusions:

• The evolution of perforin is characterized by complex birth-and-death processes.
• Gene duplication, pseudogenization, and amplification are key events in perforin evolution.
• Perforin-1 loci are conserved across mammals, reptiles, amphibians, and teleosts, indicating shared ancestry.