Deciphering pervasive domestication and active "dark matter" of proviruses in prokaryotes via precision border mapping.

ProBord and ProAct reveal that over 430,000 proviruses in prokaryotes contain diverse functional genes, with 101 dark proviruses linked to pathogenic bacteria.

• Why it matters: Understanding provirus borders and functions is crucial for deciphering their roles in bacterial evolution, pathogenicity, and antibiotic resistance, which are often hidden due to detection challenges.
• What they did: Using ProBord for single-base-precision border mapping on a large database, combined with ProAct for activity detection, the study identified and characterized both annotated and previously overlooked proviruses.
• The result: This approach uncovers the pervasive domestication of proviruses, highlights their functional diversity, and enables reverse mining of dark, pathogenic-associated proviruses, advancing insights into their evolutionary dynamics.