Suppression of Methylation-Mediated Transcriptional Gene Silencing by βC1-SAHH Protein Interaction during Geminivirus-Betasatellite Infection
Figure 1
TYLCCNB reduces TYLCCNV DNA methylation genome-wide.
N. benthamiana plants were inoculated with TYLCCNV alone or in combination with TYLCCNB. Samples were prepared by pooling six leaves from six systemically infected plants 21 days post-inoculation. DNA extracts were obtained, and the circular viral genome was divided into six fragments and PCR amplified after bisulfite treatment. Twenty clones from each fragment were sequenced. (A) The TYLCCNV genome is depicted in linear form, beginning within the conserved hairpin located in the intergenic region (IR). The positions of viral genes are shown by arrows. The six fragments used for bisulfite sequencing are indicated (MeA1 to MeA6). (B) The graph shows the total number of methylated cytosines at each position in the TYLCCNV genome, from a total of 20 sequenced clones, in different sequence contexts (CG red, CHH green, CNG blue). (C) As in (B), except DNA was obtained from plants co-inoculated with TYLCCNV + TYLCCNB. (D) The sequence contexts of all cytosines in the ∼2,737 bp TYLCCNV strain Y10 genome are indicated. (E) The histogram shows the percentage of cytosine residues methylated in different sequence contexts in the TYLCCNV genome in plants inoculated with TYLCCNV alone or together with TYLCCNB. Student's t test was performed on methylation values using individual clones as data points. The double asterisks indicate a significant difference between samples with and without TYLCCNB at the 99% confidence interval.