Rapid genome shrinkage in a self-fertile nematode reveals sperm competition proteins.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 29302007.
- Also identified by DOI 10.1126/science.aao0827 and PMC identifier 5789457.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
To reveal impacts of sexual mode on genome content, we compared chromosome-scale assemblies of the outcrossing nematode <i>Caenorhabditis nigoni</i> to its self-fertile sibling species, <i>C. briggsae</i><i>C. nigoni</i>'s genome resembles that of outcrossing relatives but encodes 31% more protein-coding genes than <i>C. briggsae</i><i>C. nigoni</i> genes lacking <i>C. briggsae</i> orthologs were disproportionately small and male-biased in expression. These include the <i>male secreted short</i> (<i>mss</i>) gene family, which encodes sperm surface glycoproteins conserved only in outcrossing species. Sperm from <i>mss</i>-null males of outcrossing <i>C. remanei</i> failed to compete with wild-type sperm, despite normal fertility in noncompetitive mating. Restoring <i>mss</i> to <i>C. briggsae</i> males was sufficient to enhance sperm competitiveness. Thus, sex has a pervasive influence on genome content that can be used to identify sperm competition factors.
Medical subject headings
- Caenorhabditis
- Glycoproteins
- Helminth Proteins
- Hermaphroditic Organisms
- Self-Fertilization
- Spermatozoa