Co-option of an endogenous retrovirus envelope for host defense in hominid ancestors.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 28397686.
- Also identified by DOI 10.7554/eLife.22519 and PMC identifier 5388530.
- 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
Endogenous retroviral sequences provide a molecular fossil record of ancient infections whose analysis might illuminate mechanisms of viral extinction. A close relative of gammaretroviruses, HERV-T, circulated in primates for ~25 million years (MY) before apparent extinction within the past ~8 MY. Construction of a near-complete catalog of HERV-T fossils in primate genomes allowed us to estimate a ~32 MY old ancestral sequence and reconstruct a functional envelope protein (ancHTenv) that could support infection of a pseudotyped modern gammaretrovirus. Using ancHTenv, we identify monocarboxylate transporter-1 (MCT-1) as a receptor used by HERV-T for attachment and infection. A single HERV-T provirus in hominid genomes includes an <i>env</i> gene (hsaHTenv) that has been uniquely preserved. This apparently exapted HERV-T <i>env</i> could not support virion infection but could block ancHTenv mediated infection, by causing MCT-1 depletion from cell surfaces. Thus, hsaHTenv may have contributed to HERV-T extinction, and could also potentially regulate cellular metabolism.
Medical subject headings
- Endogenous Retroviruses
- Gene Products, env
- Hominidae