Project description:The genome structrure of domesticated species is influenced by complexity of breeding practices exercised by humans. Hokkaido is the northern-most regio of Japan, and one of northern limit of rice cultivation of world. The climatic conditions of Hokkaido are considered to be unsuitable for rice cultivation. Rice breeding programs of Hokkaido have focused on adaptability to specific local environmental condiitons (such as short growth period, low temperature conditions). These specific selection pressures have generated the unique genetic structures of Hokkaido rice cultivars. The genotype of sixty-three Hokkaido rice varieties were already analyzed by SSR marker, and the results showed that Hokkaido rice varieties were classified into six groups (Shinada et al, 2014). The unique genomic structures of six groups may have related to specific gene expression. This study analyze the gene expression profiles of Hokkaido rice variety.
Project description:In this study, we used a cross-species network approach to uncover nitrogen (N)-regulated network modules conserved across a model and a crop species. By translating gene network knowledge from the data-rich model Arabidopsis (Arabidopsis thaliana, ecotype Columbia-0) to a crop, rice (Oryza sativa spp. japonica (Nipponbare)), we identified evolutionarily conserved N-regulatory modules as targets for translational studies to improve N use efficiency in transgenic plants.
Project description:The genome structrure of domesticated species is influenced by complexity of breeding practices exercised by humans. Hokkaido is the northern-most regio of Japan, and one of northern limit of rice cultivation of world. The climatic conditions of Hokkaido are considered to be unsuitable for rice cultivation. Rice breeding programs of Hokkaido have focused on adaptability to specific local environmental condiitons (such as short growth period, low temperature conditions). These specific selection pressures have generated the unique genetic structures of Hokkaido rice cultivars. The genotype of sixty-three Hokkaido rice varieties were already analyzed by SSR marker, and the results showed that Hokkaido rice varieties were classified into six groups (Shinada et al, 2014). The unique genomic structures of six groups may have related to specific gene expression. This study analyze the gene expression profiles of Hokkaido rice variety. Akage, Hayayuki, Sorachi, Yukara, Norin No15, Hoshinoyume and Kitaake are classified into group I, II, IIIa, IIIb, IV, V and V, respectively. Full-expanded third leaf blade was used for this study. Biological replicates; 2 (Yukara, Kitaake) , 3 (Akage, Hayayuki, Sorachi, Norin No.15, Hoshinoyume). 1 samples derived from 5 plants grown under same conditons
Project description:To understand the evolution of imprinting mechanisms in the rice species Oryza sativa, we analyzed DNA methylation, transcription and small RNA expression in embryo and endosperm. Cultivars chosen to represent the genetic diversity of cultivated Oryza sativa comprised Nipponbare and Kitaake of the japonica subspecies, and IR64 and 93-11 cultivars of the indica subspecies. While imprinted expression is generally conserved among rice cultivars, approximately 10% of imprinted genes show imprinting divergence across the four cultivars. Analyses of DNA methylation and small RNAs revealed that small RNA producing loci are closely associated with genic regions and four times more likely to be imprinted than genes. However, imprinting divergence most often correlated with DNA methylation epimutations. Correlative epialleles were largely stable within subspecies. Small indels and transposable element insertions were found at half of the epimutated loci and associated with imprinting divergence at half of the remaining loci. Correlating epigenetic and genetic variation occurred at key regulatory regions – the promoter and transcription start site of maternally-biased genes, and the promoter and gene body of paternally-biased genes. Our results reinforce models for the role of maternal-specific DNA hypomethylation in imprint formation at both maternally and paternally biased genes, and highlight the role of transposition events and epimutation in rice imprinting evolution.
Project description:Iron (Fe) is an essential element to plants, but can be harmful if accumulated to toxic concentrations. Fe toxicity can be a major nutritional disorder in rice (Oryza sativa) when cultivated under waterlogged conditions, as a result of excessive Fe solubilization of in the soil. However, little is known about the basis of Fe toxicity and tolerance at both physiological and molecular level. Here we aim at understand the genotypic differences in two rice cultivars with contrasting phenotypes under Fe toxicity.
Project description:Transcriptional profiling of Oryza sativa japonica Nipponbare roots after 14 days post inoculation with Azoarcus olearius BH72, the goal is to understand the transcriptomic response of rice roots to colonization by bacterial endophyte