Project description:Plants adapt to environmental changes by adjusting growth and defense, and the role of epigenetic modifications in this process is unclear. Sensing and adjusting to environmental changes are more important in certain tissues such as epidermis, vasculature, meristem, and reproductive tissues. These tissues possess sensory plastids that are specialized in environmental sensing. We show perturbation of four sensory plastid proteins MSH1, PPD3, CUE1, and SAL1 induce gene expression and DNA methylation changes targeted to networks associated to environmental sensing, with significant overlap with hda6-induced CHG hypermethylated genes at 12-hr daylength. At 16-hr daylength, hda6 loses CHG hypermethylation in gene body, and sensory plastid mutants have weaker phenotypes and DNA methylation- and gene expression- associated gene networks. We show daylength-responsive epistatic interaction between sensory plastid mutants with hda6. We also show that hda6 mutation confers daylength memory and, with msh1, enhanced tolerance to heat stress and biotic stress. These results suggest that HDA6 mediates programmed adjustments in plant phenotype triggered by sensory plastid-to-nucleus retrograde signaling in response to daylength and environmental cues.
Project description:Plants adapt to environmental changes by adjusting growth and defense, and the role of epigenetic modifications in this process is unclear. Sensing and adjusting to environmental changes are more important in certain tissues such as epidermis, vasculature, meristem, and reproductive tissues. These tissues possess sensory plastids that are specialized in environmental sensing. We show perturbation of four sensory plastid proteins MSH1, PPD3, CUE1, and SAL1 induce gene expression and DNA methylation changes targeted to networks associated to environmental sensing, with significant overlap with hda6-induced CHG hypermethylated genes at 12-hr daylength. At 16-hr daylength, hda6 loses CHG hypermethylation in gene body, and sensory plastid mutants have weaker phenotypes and DNA methylation- and gene expression- associated gene networks. We show daylength-responsive epistatic interaction between sensory plastid mutants with hda6. We also show that hda6 mutation confers daylength memory and, with msh1, enhanced tolerance to heat stress and biotic stress. These results suggest that HDA6 mediates programmed adjustments in plant phenotype triggered by sensory plastid-to-nucleus retrograde signaling in response to daylength and environmental cues.
Project description:The PPD3 genomic DNA was cloned in the binary vector pCAMBIA1302C with its native promoter of about 1.5 kb and was tagged with GFP. Wild type Col-0 plants were transformed by the dipping method and screened for positive plants by hygromycin and also by PCR primers for presence of the transgene.