Figure 6.

PuWRKY31 histone acetylation and PuHLS1 expression between NG and BNG fruits. A, The histone acetylation level of PuActin chromatin by H3ac or H4ac between NG and BNG fruits. The results were normalized to the amount of input DNA. B, The histone acetylation level at different regions of the PuWRKY31 chromatin by H3ac or H4ac between NG and BNG fruits as determined by ChIP-PCR. Fruit harvested at commercial harvest day in 2014 were used. The results were normalized relative to the amount of PuActin. Each experiment was repeated three times. The ChIP assay was repeated three times and the enriched DNA fragments in each ChIP were used as one biological replicate for qPCR. Error bars represent the se, and asterisks indicate significant difference as determined by Student’s t test (**P < 0.01). C, Expression of PuHLS1 during NG and BNG fruit development as determined by RT-qPCR. Fruit samples were the same as in Figure 1. Numbers under the x axis indicate DAFB. Three biological replicates were analyzed, and the error bars represent the se. Asterisks indicate significant difference as determined by Student’s t test (**P < 0.01). D, EMSA analysis of PuHLS1 binding to the CDS of PuWRKY31. The hot probe was biotin-labeled PuWRKY31 CDS, while the cold probe was a nonlabeled competitive probe (with a 100-fold higher concentration than the hot probe). PuHLS1-GST was purified and used for DNA-binding assays. The sequence of the biotin labeled probe is shown.