DGR and bRT–Avd:RNAΔ98 RNP. Credit: Nature (2025). DOI: 10.1038/s41586-024-08405-w

Diversity-generating retroelements (DGRs) are found in the genomes of microorganisms across the globe—from the arctic permafrost to Yellowstone's hot springs and the human gut. DGRs are able to reverse-transcribe RNA back to DNA in a form of natural gene-editing. This process accelerates the evolution of proteins to help microorganisms adapt to changing environments.

Using , Partho Ghosh's lab at UC San Diego has figured out the first steps of this accelerated by visualizing the relevant proteins and RNA. They found that RNA especially controlled accelerated evolution, forming structures that started, maintained and stopped the process at the right place.

DGR RNA (orange and red ribbons) and proteins (dark and light blue surfaces) responsible for the first steps of accelerated protein evolution. The red RNA ribbon is the segment that is reverse-transcribed back to DNA. Credit: Partho Ghosh lab / UC San Diego

These RNA structures, which were identified in the DGRs of many microorganisms, limited accelerated evolution to proteins needed for adaptation while protecting other essential ones from harm. This research deepens our understanding of the evolutionary origin of DGRs and may be applicable to future gene-editing techniques.

The findings are in the journal Nature.

More information: Sumit Handa et al, RNA control of reverse transcription in a diversity-generating retroelement, Nature (2025).

Journal information: Nature

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