Evidence that siRNAs function as guides, not primers, in the Drosophila and human RNAi pathways
Graduate School of Biomedical Sciences; Department of Biochemistry and Molecular Pharmacology
Life Sciences | Medicine and Health Sciences
In Drosophila, two features of small interfering RNA (siRNA) structure--5' phosphates and 3' hydroxyls--are reported to be essential for RNA interference (RNAi). Here, we show that as in Drosophila, a 5' phosphate is required for siRNA function in human HeLa cells. In contrast, we find no evidence in flies or humans for a role in RNAi for the siRNA 3' hydroxyl group. Our in vitro data suggest that in both flies and mammals, each siRNA guides endonucleolytic cleavage of the target RNA at a single site. We conclude that the underlying mechanism of RNAi is conserved between flies and mammals and that RNA-dependent RNA polymerases are not required for RNAi in these organisms.
DOI of Published Version
Mol Cell. 2002 Sep;10(3):537-48.
Schwarz DS, Hutvagner G, Haley B, Zamore PD. (2002). Evidence that siRNAs function as guides, not primers, in the Drosophila and human RNAi pathways. Morningside Graduate School of Biomedical Sciences Student Publications. https://doi.org/10.1016/S1097-2765(02)00651-2. Retrieved from https://escholarship.umassmed.edu/gsbs_sp/1085