Although DNA exchange through cellular contact has been described in archaea, the mode of DNA transport has not been studied at the molecular level. Based on the assumption that DNA transport has a role in DNA repair and involves membrane proteins, Albers and colleagues looked at published microarray data describing changes in gene expression in Sulfolobus acidocaldarius following exposure to UV light. They identified three clustered genes that had increased expression, which they termed cedA (crenarchaeal system for exchange of DNA A), cedA1 and cedA2. Another highly upregulated gene, cedB, encodes a homologue of the ATPase VirB4, a bacterial conjugation protein. In agreement with their role in DNA exchange, DNA transfer following UV treatment was blocked in mutants lacking CedA or CedB. Furthermore, the authors showed that this system works as a DNA importer in the UV-damaged cell.