Unknown

Dataset Information

0

E. coli RNase I exhibits a strong Ca2+-dependent inherent double-stranded RNase activity.


ABSTRACT: Since its initial characterization, Escherichia coli RNase I has been described as a single-strand specific RNA endonuclease that cleaves its substrate in a largely sequence independent manner. Here, we describe a strong calcium (Ca2+)-dependent activity of RNase I on double-stranded RNA (dsRNA), and a Ca2+-dependent novel hybridase activity, digesting the RNA strand in a DNA:RNA hybrid. Surprisingly, Ca2+ does not affect the activity of RNase I on single stranded RNA (ssRNA), suggesting a specific role for Ca2+ in the modulation of RNase I activity. Mutation of a previously overlooked Ca2+ binding site on RNase I resulted in a gain-of-function enzyme that is highly active on dsRNA and could no longer be stimulated by the metal. In summary, our data imply that native RNase I contains a bound Ca2+, allowing it to target both single- and double-stranded RNAs, thus having a broader substrate specificity than originally proposed for this traditional enzyme. In addition, the finding that the dsRNase activity, and not the ssRNase activity, is associated with the Ca2+-dependency of RNase I may be useful as a tool in applied molecular biology.

SUBMITTER: Grunberg S 

PROVIDER: S-EPMC8136782 | biostudies-literature |

REPOSITORIES: biostudies-literature

Similar Datasets

| S-EPMC3162437 | biostudies-literature
| S-EPMC9674317 | biostudies-literature
| S-EPMC7373196 | biostudies-literature
| S-EPMC3939876 | biostudies-literature
| S-EPMC65640 | biostudies-literature
| S-EPMC4046343 | biostudies-literature
| S-EPMC528802 | biostudies-literature
| S-EPMC3794599 | biostudies-literature
| S-EPMC3082872 | biostudies-literature
| S-EPMC5351666 | biostudies-literature