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Updated: Aug 13, 2026
07:10
Conformational Evaluation of HIV-1 Trimeric Envelope Glycoproteins Using a Cell-based ELISA Assay
Published on: September 14, 2014
Dynamic evolution of retroviral envelope-derived sequences in primates
Koichi Kitao1,2, Kirill Kryukov3,4, Lihua Jin5,6
1Laboratory of Genome and Epigenome Dynamics, Department of Animal Sciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan.
Virus Evolution
|August 12, 2026
Summary
Researchers explored primate endogenous retroviral envelope (env) genes, discovering a new tarsier env gene, env-Tar1, with cell fusion activity. This highlights the dynamic evolution and co-option of these ancient viral remnants.
Area of Science:
- Evolutionary biology
- Genomics
- Virology
Background:
- Endogenous retroviruses (ERVs) are remnants of ancient retroviral integrations found in host genomes.
- Some ERV envelope (env) genes, encoding fusogenic proteins, are retained and potentially co-opted by primate hosts.
- The evolutionary dynamics and functional significance of these co-opted env genes are not fully understood.
Purpose of the Study:
- To investigate the evolutionary dynamics of primate endogenous retroviral env genes.
- To identify and characterize co-opted env-derived genes across primate lineages.
- To provide functional evidence for the role of a newly identified env gene in a specific primate lineage.
Main Methods:
- Screened and compared env open reading frames (ORFs) from 247 primate genomes.
- Identified nearly intact env-ORFs (≥400 amino acids) and analyzed their copy numbers.
- Utilized sequence similarity clustering to distinguish evolutionary patterns of env-derived genes.
- Performed in vitro experiments to assess the cell fusion activity of a novel env ortholog.
Main Results:
- Identified 8683 nearly intact env-ORFs across primate species, with copy numbers varying significantly.
- Differentiated long-term co-opted env genes (low copy number, conserved) from rapidly turning-over env-ORFs.
- Discovered and named a novel, single-copy env ortholog, env-Tar1, conserved in Tarsiiformes.
- Demonstrated env-Tar1's cell fusion activity in vitro, confirming its functional co-option in tarsiers.
- Observed functional loss in some co-opted env genes due to mutations in specific primate lineages.
Conclusions:
- Primate endogenous retroviral env genes exhibit diverse evolutionary trajectories, including functional co-option and loss.
- The newly identified env-Tar1 provides the first functional evidence of env gene co-option in a tarsier lineage.
- Dynamic turnover of env-derived genes may result from host-virus co-evolutionary arms races.
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