Impacts of VTC3 and VTC2 on transcriptome under illumination in Arabidopsis
VITAMIN C DEFECTIVE 3 (VTC3) is a distinctive protein with both kinase and phosphatase domains and is essential for ascorbate accumulation in Arabidopsis. In the vtc3 mutant, ascorbate levels are approximately 50% of those in the wild type, and light-induced increases in the ascorbate pool size are markedly suppressed. The regulation of the ascorbate pool size by light involves GDP-L-galactose phosphorylase (VTC2), a key biosynthetic enzyme. To elucidate the physiological function of VTC3, we compared the transcriptomes of vtc3, wild-type, and vtc2 plants. Contrary to expectations, the loss of VTC3 had minimal impact on the transcriptome. Among the few genes upregulated in the vtc3 mutant, several were related to pathogen responses. Overall design: RNA-seq profiling of wild type, vtc2, and vtc3 shoots under illumination. After 48 hours of dark adaptation, the plants were exposed to light for 6 hours.