Fig. 3: Rep hijacks RAD51 and RPA1A to facilitate viral DNA amplification.

a Y2H screening pinpointed RAD51 and RPA1A as targets of Rep protein. The negative controls are AD/BD empty vectors. At least 16 independent colonies for each combination were tested and showed similar results. b Co-IP assay validated interactions of Rep with RAD51 and RPA1A in planta. FM-FVE⁷⁷, FM-CYCB1, and Coomassie blue staining of blots serve as negative and loading controls, respectively. The experiments were repeated twice with similar results. c ChIP-qPCR assay shows the binding of RAD51 and RPA1A on viral genome. IgG is a negative control. Each dot in the bar plot represents one replicate, experiments were performed with 36 plants/replicate. Data are presented as mean ± SD (n = 3 biological replicates). d IGV file shows transcript levels of RAD51 and RPA1A in mock-treated or virus-inoculated Col-0 and atxr5 atxr6 (normalized by RPKM). Scales for the distinct loci are shown on left as solid lines. e Representative phenotypes of CaLCuV-inoculated Col-0, atxr5 atxr6, rpa1a, rad51 (-/-), rad51 (+/-), rad51 (-/-) atxr5 atxr6, and rad51 (+/-) atxr5 atxr6 plants. Photographs were taken at 16 dpi. Scale bars, 1 cm. f Percentages of symptomatic plants induced by CaLCuV-inoculation in indicated backgrounds at 11, 13, and 15 dpi. g q-PCR assays show the amount of viral DNA A in CaLCuV-inoculated plants indicated at 16 dpi. In (f) and (g), each dot in the bar plot represents one replicate, most experiments were performed with 36 plants/replicate except for rad51(-/-) and rad51(-/-) atxr5 atxr6 where 24 and 15 plants were used for each replicate, respectively. Data are presented as mean ± SD (n = 3 biological replicates). Normalization of viral DNA was conducted as in Fig. 2g. Statistics in Figs. 3c, f, and g were performed with unpaired two-tailed student t-test, *, **, *** and ****, P < 0.05, 0.01, 0.001, and 0.0001, respectively. Source data are provided in the Source Data File.