ArticleProceedings of the National Academy of Sciences of the United States of America2012
Ancestral capture of syncytin-Car1, a fusogenic endogenous retroviral envelope gene involved in placentation and conserved in Carnivora.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2012. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 86 papers.
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86 citing papers in PubMed, 132 citations in OpenAlex.
- An ancient alpharetrovirus lineage in bats: Evolutionary insights and possible roles in reproduction.PLoS genetics · 2026Article
- Cross-species insights into placental evolution and diseases at the single-cell resolution.Nature communications · 2026Article
- Viviparity and beyond: captured endogenous retroviral envelope genes drive teleost physiological innovations.Molecular biology and evolution · 2026Article
- Morpho-functional uterine and placental dynamics during establishment and maintenance of canine pregnancy, from early trophoblast invasion to parturition.The Journal of reproduction and development · 2026Review
- Morphological and functional aspects of the canine placental barrier: evidence supporting a deciduo-chorial model.Reproduction & fertility · 2025Article
- Trophoblast Fusion in Hypertensive Disorders of Pregnancy and Preeclampsia.International journal of molecular sciences · 2025Review
- Histological Changes in the Cat Placenta Throughout Gestation.Veterinary sciences · 2025Article
- Sodium-dependent phosphate transporter PiT1/SLC20A1 as the receptor for the endogenous retroviral envelope syncytin-B involved in mouse placenta formation.Journal of virology · 2024Article
- Disruption of maternal vascular remodeling by a fetal endoretrovirus-derived gene in preeclampsia.Genome biology · 2024Article
- Progressive Exaptation of Endogenous Retroviruses in Placental Evolution in Cattle.Biomolecules · 2023Review
- Evolutionary conservation of an ancient retroviralJournal of virology · 2023Article
- Envelope Recombination: A Major Driver in Shaping Retroviral Diversification and Evolution within the Host Genome.Viruses · 2023Review
- A Frame-by-Frame Glance at Membrane Fusion Mechanisms: From Viral Infections to Fertilization.Biomolecules · 2023Review
- Dynamic Evolution of Retroviral Envelope Genes in Egg-Laying Mammalian Genomes.Molecular biology and evolution · 2023Article
- Unique Structure and Distinctive Properties of the Ancient and Ubiquitous Gamma-Type Envelope Glycoprotein.Viruses · 2023Review
- Reconstitution of Fusion-Competent Human Placental Fusogen Syncytin-2.The Journal of membrane biology · 2022Article
- Cross-species transmission of an ancient endogenous retrovirus and convergent co-option of its envelope gene in two mammalian orders.PLoS genetics · 2022Article
- Review
- Deep-Time Structural Evolution of Retroviral and Filoviral Surface Envelope Proteins.Journal of virology · 2022Article
- Article
26 more citing papers are in PubMed but not listed here.
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Authors and funding
8 authors at 6 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Syncytins are envelope protein genes of retroviral origin that have been captured for a function in placentation. Two such genes have already been identified in simians, two distinct, unrelated genes have been identified in Muridae, and a fifth gene has been identified in the rabbit. Here, we searched for similar genes in the Laurasiatheria clade, which diverged from Euarchontoglires--primates, rodents, and lagomorphs--shortly after mammalian radiation (100 Mya). In silico search for envelope protein genes with full-coding capacity within the dog and cat genomes identified several candidate genes, with one common to both species that displayed placenta-specific expression, which was revealed by RT-PCR analysis of a large panel of tissues. This gene belongs to a degenerate endogenous retroviral element, with precise proviral integration at a site common to dog and cat. Cloning of the gene for an ex vivo pseudotype assay showed fusogenicity on both dog and cat cells. In situ hybridization on placenta sections from both species showed specific expression at the level of the invasive fetal villi within the placental junctional zone, where trophoblast cells fuse into a syncytiotrophoblast layer to form the maternofetal interface. Finally, we show that the gene is conserved among a series of 26 Carnivora representatives, with evidence for purifying selection and conservation of fusogenic activity. The gene is not found in the Pholidota order and, therefore, it was captured before Carnivora radiation, between 60 and 85 Mya. This gene is the oldest syncytin gene identified to date, and it is the first in a new major clade of eutherian mammals.
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