Ro ribonucleoproteins contribute to the resistance of Deinococcus radiodurans to ultraviolet irradiation

The genome of the radiation-resistant eubacterium Deinococcus radiodurans c ontains an ortholog of an RNA-binding protein known as the Ro 60-kD autoant igen. This protein, which was previously identified only in higher eukaryot es, is normally bound to small RNAs known as Y RNAs. We show that the Ro pr otein ortholog Rsr contributes to the resistance of D. radiodurans to UV ir radiation. Rsr binds several small RNAs, encoded upstream of rsr, that accu mulate following UV irradiation. One of these RNAs resembles a Y RNA. These results suggest that Ro RNPs could similarly contribute to the recovery of higher cells following UV irradiation.