FIGURE 5.

The CREF7-E554A mutation decreases editing of rpoA, a non-cognate editing site. A, poisoned primer extension assay was used to determine rpoA editing site conversion. Control lanes show oligonucleotide (O), unedited template (C), and edited template (T). B, editing of rpoA was about 70% in wild type and knock-out plants. Expression of CREF7-E554A in the CREF7 knock-out line resulted in a decrease in rpoA editing to about 45%. Three leaf samples were analyzed from wild type plants (WT) and cref7-1 knock-out (KO) plants. A single leaf sample was analyzed from each of three independent integration events for these backgrounds and transgenes: wild type plants with CREF7 transgene (WT + CREF7); and cref7 with CREF7-E554A (KO + CREF7-E554A). For statistical analysis, the Student's t test was performed with significance indicated as * and ** for >0.05 and >0.005 at the 0.05 level, respectively. Error bars show the S.D. of the three leaf samples from three independent plants.