A widely employed germ cell marker is an ancient disordered protein with reproductive functions in diverse eukaryotes.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 27718356.
- Also identified by DOI 10.7554/eLife.19993 and PMC identifier 5098910.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The advent of sexual reproduction and the evolution of a dedicated germline in multicellular organisms are critical landmarks in eukaryotic evolution. We report an ancient family of GCNA (germ cell nuclear antigen) proteins that arose in the earliest eukaryotes, and feature a rapidly evolving intrinsically disordered region (IDR). Phylogenetic analysis reveals that GCNA proteins emerged before the major eukaryotic lineages diverged; GCNA predates the origin of a dedicated germline by a billion years. <i>Gcna</i> gene expression is enriched in reproductive cells across eukarya - either just prior to or during meiosis in single-celled eukaryotes, and in stem cells and germ cells of diverse multicellular animals. Studies of <i>Gcna-</i>mutant <i>C. elegans</i> and mice indicate that GCNA has functioned in reproduction for at least 600 million years. Homology to IDR-containing proteins implicated in DNA damage repair suggests that GCNA proteins may protect the genomic integrity of cells carrying a heritable genome.
Medical subject headings
- Antigens, Nuclear
- Evolution, Molecular
- Germ Cells
- Reproduction