Double-Stranded RNA Triggers Generalized Translational Arrest in Xenopus Oocytes

Abstract

Controls of gene expression which act at the translational level can he rapidly activated and readily reversed. The impact of double-stranded RNA on translational control is of significant interest as a number of studies point to its ability to directly activate generalized translational arrest. This activity is observed in in vitro systems stimulated by native double-stranded RNAs or synthetic homopolymers and is inferred in virally infected cells in tissue culture. Significantly, however, this activity has never been studied in an intact cell system using RNAs of known secondary structure. In this study we arrest total cellular translation in intact Xenopus oocytes by micro-injecting them with α-globin-derivative mRNAs containing defined double-stranded segments. The ability of these mRNAs to directly activate translational arrest in oocytes substantiates the potential role for this activity in vivo and establishes a well-characterized whole cell system for its further study.