Direct cell-to-cell transmission of retrotransposons.

Retrotransposons in Drosophila can infect germline cells via a novel Envelope-independent cell-to-cell transmission mechanism involving sORF2 proteins.

• Why it matters: Understanding how transposable elements spread beyond their host cell is crucial for insights into genome evolution and viral evolution, especially since most lack traditional fusogenic proteins.
• What they did: The study used genetics, imaging, and electron microscopy to demonstrate that sORF2 proteins localize to somatic protrusions that contact oocyte membranes, enabling capsid transfer without envelope proteins.
• The result: This discovery of a widespread, noncanonical transmission pathway in retrotransposons and some viruses highlights a new mode of genetic element spread, broadening knowledge of virus-host interactions.