A light signaling factor, ELONGATED HYPOCOTYL 5 (HY5) interacts with Histone deacetylase 9 (HDA9) to play a suppressive role in the glucosinolate biosynthesis in Arabidopsis

In this study, we found that a light signaling factor, Long Hypocotyl 5 (HY5) is closely involved in the regulation of GSLs contents in light condition. In addition, HY5 was shown to physically interact with a histone deacetylase HDA9 and bind to proximal promoter region of MYB29 and IMD1 to suppress aliphatic GSL biosynthetic process. These results demonstrate that HY5 acts to suppress GSL accumulation at daytime, thus properly modulating the GSL contents on a daily basis of Arabidopsis plant. Performed transcriptome analysis and targeted metabolite profiling of seedlings from the Arabidopsis loss-of-function mutants hy5-215 and hda9-1 compared to Col-0 wild-type plants.