Project description:High ozone (O3) concentration causes serious damages in plant productivity. Climate models forecast that ground O3 level in the future will reach phytotoxic range, resulting in crop yield losses. With an ultimate goal to screen molecular factors to minimize losses of crop production by the rise of O3 level, we have started an investigation on effects of O3 on rice using rice DNA chip. Herein, we have utilized the samples of dry mature rice seeds harvested in an ozone-sensitive rice cultivar (Oryza sativa L. indica cv. Takanari) and a tolerant cultivar (Oryza sativa L. japonica cv. Koshihikari) which were fumigated with ambient air (mean O3: 32.7 ppb) in small open-top chambers (OTCs). First, we extracted total RNA from dry mature rice seeds of Takanari and Koshihikari using a modified protocol based on cethyltrimethylammonium bromide extraction buffer and phenol-chloroform-isoamylalcohol treatment. Furthermore, to perform microarray analysis using the Agilent 4x44 rice DNA Chip and the dye-swap method, we designed a balanced block design comparing seeds in an ambient air-fumigated rice cultivar and those in a filtered air-fumigated rice cultivar. Direct comparison of Koshihikari and Takanari O3 transcriptomes in seeds of rice plants fumigated with ambient O3 in OTCs successfully showed that genes encoding proteins involved in jasmonic acid, GABA biosynthesis, cell wall and membrane modification, starch mobilization, and secondary metabolite biosynthesis are differently regulated in an O3-sensitive cv. Takanari and a tolerant cv. Koshihikari.
Project description:High ozone (O3) concentration causes serious damages in plant productivity. Climate models forecast that ground O3 level in the future will reach phytotoxic range, resulting in crop yield losses. With an ultimate goal to screen molecular factors to minimize losses of crop production by the rise of O3 level, we have started an investigation on effects of O3 on rice using rice DNA chip. Herein, we have utilized the samples of dry mature rice seeds harvested in an ozone-sensitive rice cultivar (Oryza sativa L. indica cv. Takanari) and a tolerant cultivar (Oryza sativa L. japonica cv. Koshihikari) which were fumigated with ambient air (mean O3: 32.7 ppb) in small open-top chambers (OTCs). First, we extracted total RNA from dry mature rice seeds of Takanari and Koshihikari using a modified protocol based on cethyltrimethylammonium bromide extraction buffer and phenol-chloroform-isoamylalcohol treatment. Furthermore, to perform microarray analysis using the Agilent 4x44 rice DNA Chip and the dye-swap method, we designed a balanced block design comparing seeds in an ambient air-fumigated rice cultivar and those in a filtered air-fumigated rice cultivar. Direct comparison of Koshihikari and Takanari O3 transcriptomes in seeds of rice plants fumigated with ambient O3 in OTCs successfully showed that genes encoding proteins involved in jasmonic acid, GABA biosynthesis, cell wall and membrane modification, starch mobilization, and secondary metabolite biosynthesis are differently regulated in an O3-sensitive cv. Takanari and a tolerant cv. Koshihikari.
Project description:Four-week-old Arabidopsis thaliana (Col-0) plants were fumigated for 1 h with 10 parts per million (ppm) nitrogen dioxide (NO2) to analyse leaf transcriptome changes induced by this air pollutant relative to air-fumigated control plants.
Project description:Isoprene is a well-studied volatile hemiterpene that protects plants from abiotic stress through mechanisms that are not fully understood. The antioxidant and membrane stabilizing potential of isoprene are the two most commonly invoked mechanisms. However, isoprene also affects phenylpropanoid metabolism, suggesting an additional role as a signaling molecule. In this study, microarray based gene expression profiling reveals widespread transcriptional reprogramming of Arabidopsis thaliana plants fumigated for 24 hrs with a physiologically relevant concentration of isoprene. Functional enrichment analysis of fumigated plants revealed enhanced heat- and light-stress-responsive processes in response to isoprene. Isoprene induced a network enriched in ERF and WRKY transcription factors, which may play a role in stress tolerance. The isoprene-induced upregulation of phenylpropanoid biosynthetic genes was specifically confirmed using quantitative reverse transcription polymerase chain reaction. These results support a role for isoprene as a signaling molecule, in addition to its possible roles as an antioxidant and membrane thermoprotectant.
Project description:High ozone (O3) concentration causes serious damages in plant productivity. Climate models forecast that ground O3 level in the future will reach phytotoxic range, resulting in crop yield losses. With an ultimate goal to screen molecular factors to minimize losses of crop production by the rise of O3 level, we have started an investigation on effects of O3 on rice using rice DNA chip. Herein, we have utilized the samples of dry mature rice seeds harvested in an ozone-sensitive rice cultivar (Oryza sativa L. indica cv. Takanari) and a tolerant cultivar (Oryza sativa L. japonica cv. Koshihikari) which were fumigated with ambient air (mean O3: 32.7 ppb) in small open-top chambers (OTCs). First, we extracted total RNA from dry mature rice seeds of Takanari and Koshihikari using a modified protocol based on cethyltrimethylammonium bromide extraction buffer and phenol-chloroform-isoamylalcohol treatment. Furthermore, to perform microarray analysis using the Agilent 4x44 rice DNA Chip and the dye-swap method, we designed a balanced block design comparing seeds in an ambient air-fumigated rice cultivar and those in a filtered air-fumigated rice cultivar. Direct comparison of Koshihikari and Takanari O3 transcriptomes in seeds of rice plants fumigated with ambient O3 in OTCs successfully showed that genes encoding proteins involved in jasmonic acid, GABA biosynthesis, cell wall and membrane modification, starch mobilization, and secondary metabolite biosynthesis are differently regulated in an O3-sensitive cv. Takanari and a tolerant cv. Koshihikari.