Exonucleolytic degradation of double-stranded RNA by an activity in Xenopus laevis germinal vesicles

We have identified, in extracts from Xenopus laevis germinal vescicles, a 5' exonuclease acitivity that cleaves double-stranded RNA (dsRNA). Features of the 5' ends of dsRNAs determine whether the strands are symmetrically or asymmetrically degraded.