Fig. 4.

Isolation of rns2-2, an Arabidopsis mutant that lacks RNS2 activity. (A) Schematic showing the organization of the RNS2 gene and the T-DNA insertion present in the rns2-2 mutant. Boxes represent exons, and lines represent introns (between exons). Start (arrow) and end (*) of the RNS2 ORF are indicated. (B) RNase activity in gel profile of protein extracts obtained from leaves of WT and rns2-2 mutant plants. A strong RNase activity in WT and absent in the rns2-2 mutant was identified as RNS2. Lanes contain 40 μg of protein. (C) SDS/PAGE stained with Coomassie Blue R-250 of samples as in B.