With the development of next generation sequencing (NGS) technology, the variation of sequences represented as SNP between cultivars becomes available at genome level. The major domestic cultivars with high yield have been developed by breeding of indica and japonica, it is important to localize the region of origin according to the genotype for further characterization of unique features of cultivars. For the localization of SNP at genome level, the paired end sequences of 6 major domestic rice cultivars, Ilmi, Ilpoom, Sulgaeng, Bakjinju, Hwayoung and Woonkwang were compared against Japonica and Indica Rice Genomes as reference genomes. The genomic DNAs were prepared from callus tissues and paired-end of the fragments were sequenced with NGS Sequencer, Illumina HISeq. About 50x coverage of paired-end sequences were trimmed according to the quality of the sequences, and errors were corrected with statistical analysis of kmers of 15. The trim-corrected sequences were mapped and variants were analyzed against reference genomes. The overall change rate of Ilmi against Nipponbare IRGSP 1.0 and Indica BGI 93-11 reference genomes were 0.92 base/1kb (1/1,079 base) and 8.09 base/1kb (1 base/123 bases), respectively. Among 6 cultivars, overall rate of Bakjinju showed the lowest overall change rate of 0,53 base/1kb, and Hwayoung showed highest frequency of 0.92 base/1kb. Compared to high level in the range of change rate of 7.0-9.3 base/1kb against indica, domestic cultivars showed lower range of change rate 0.2-3.3 base/1kb with unique local high peak against japonica genome depend on the chromosomes. Compared to assembly of genome sequences, the variation of nucleotides compared to reference sequences is much faster and simple to characterize the genotype. The types of variation and the effect on functional categories will be presented.

Spatial- and temporal-specific expression patterns are primarily regulated at the transcriptional level by the promoter. Therefore, it is important to determine the binding motifs of transcription factors to understand the networks associated with embryogenesis. Here, we used a protein-binding microarray (PBM) to determine the binding motif of OsSMF1, which is a basic leucine zipper transcription factor that is involved in the regulation of rice seed maturation. OsSMF1 (previously called RISBZ1) is known to interact with GCN4 motifs (TGA(G/C)TCA) to regulate seed storage proteins (SSPs). In addition, OsSMF1 (also known as OsbZIP58) functions as a key regulator of starch synthesis in the rice seed. Quadruple 9-mer-based PBM (Q9-PBM) and electrophoretic mobility shift assay (EMSA) experiments revealed that OsSMF1 binds to the ACGT (CCACGT(C/G)), GCN4 (TGA(G/C)TCA), and GCN4-like (GGATGAC) motifs with Kd values of 0.3353 μM, 0.6458 μM, and 1.117 μM, respectively. We also identified 60 putative OsSMF1 target genes using a combination of data from expression microarrays and RiceArrayNet (RAN) analysis. Of these OsSMF1 target genes, 20, 22, and 17 genes contained ACGT, GCN4, and GCN4-like motifs within the 2-kb promoter region, respectively. In addition to known target genes, we also identified 35 potential OsSMF1 target genes that have not been previously described in immature seeds. We also confirmed that OsSMF1 directly regulates Os03g0168500 (thioredoxin-related protein), RPBF, NAC6, and two hypothetical proteins (Os12g0621600 and Os11g0582400) in vivo. This study suggests that OsSMF1 functions in a wide range of seed development processes with specific binding affinities for three DNA binding motifs

The perturbation of the steady state of reactive oxygen species due to biotic and abiotic stresses in a plant could lead to protein denaturation through the modification of amino acid residues, including the oxidation of methionine residues. Methionine sulfoxide reductases (MSRs) catalyze the reduction of methionine sulfoxide back to the methionine residue. To assess the role of this enzyme, we generated transgenic rice using a pepper CaMSRB2 gene under the control of the rice Rab21 promoter with/without a selection marker, the bar gene. A drought resistance test on transgenic plants showed that CaMSRB2 confers drought tolerance to rice, as evidenced by less oxidative stress symptoms and a strengthened PSII quantum yield under stress conditions, and increased survival rate and chlorophyll index after the re-watering. The results from immunoblotting using a methionine sulfoxide antibody and nano-LC-MS/MS spectrometry suggest that porphobilinogen deaminase (PBGD), which is involved in chlorophyll synthesis, is a putative target of CaMSRB2. The oxidized methionine content of PBGD expressed in E. coli increased in the presence of H2O2, and the Met-95 and Met-227 residues of PBGD were reduced by CaMSRB2 in the presence of dithiothreitol. An expression profiling analysis of the overexpression lines also suggested that photosystems are less severely affected by drought stress. Our results indicate that CaMSRB2 might play an important functional role in chloroplasts for conferring drought stress tolerance in rice

With the development of next generation sequencing (NGS) technology, the variation of sequences represented as SNP between cultivars becomes available at genome level. The major domestic cultivars with high yield have been developed by breeding of indica and japonica, it is important to localize the region of origin according to the genotype for further characterization of unique features of cultivars. For the localization of SNP at genome level, the paired end sequences of 6 major domestic rice cultivars, Ilmi, Ilpoom, Sulgaeng, Baekjinju1ho, Hwayoung and Woongwang were compared against Japonica and Indica Rice Genomes as reference genomes. The genomic DNAs were prepared from callus tissues and paired-end of the fragments were sequenced with NGS Sequencer, Illumina HISeq2000. About 50x coverage of paired-end sequences were trimmed according to the quality of the sequences, and errors were corrected with statistical analysis of kmers of 15. The trim-corrected sequences were mapped and variants were analyzed against reference genomes. The overall change rate of Ilmi against Nipponbare IRGSP 1.0 and Indica BGI 93-11 reference genomes were 0.92 base/1kb (1/1,079 base) and 8.09 base/1kb (1 base/123 bases), respectively. Among 6 cultivars, overall rate of Baekjinju1ho showed the lowest overall change rate of 0,53 base/1kb, and Hwayoung showed highest frequency of 0.92 base/1kb. Compared to high level in the range of change rate of 7.0-9.3 base/1kb against indica, domestic cultivars showed lower range of change rate 0.2-3.3 base/1kb with unique local high peak against japonica genome depend on the chromosomes. Compared to assembly of genome sequences, the variation of nucleotides compared to reference sequences is much faster and simple to characterize the genotype. The types of variation and the effect on functional categories will be presented.

Rice is one of the most important crop in the world and the genome sequences of a rice cultivar, Nipponbare has been used not only for rice research, but also as the model reference genome sequences in monocotyledon species among the crops. With the development of the next generation sequencing(NGS) techniques producing high order of coverage and with the need for epigenomic analysis, the need for resequencing of the domestic rice cultivars with the reference “Nipponbare” genome sequence at the de novo level. According the simulation of Nipponbare reference genomes with Eulerian methods, the target size of maximal contig and N50 of ones of the domestic cutivar rice were estimated to be 10M and 1M, respectively. To achieve the target size, various mate-paired libraries were constructed and sequenced. With the high order of coverage obtained from domestic rice cultivar, Ilmi, with NGS technology, the effect of trimming and error correction on reads quality profiles and size distribution of contigs were analyzed. Also the computational parameters for validation of assembled contigs were analyzed. For the analysis of epigenomic methylation modification of the genome sequences, the methyl binding microarray technology was developed. The various methyl-CG binding proteins were characterized. The binding and scanning of methyl-CG domain to promoter binding microarray and their downstream genes were analyzed. Also rice mutants related to methylation were selected to understand the effect of methylation on gene expresson and its effect on phenotypes.

The surveying of binding affinity between a particular transcription factor and DNA motifs is important in order to understand the developmental specific gene expression and regulatory networks of an organism. The microarray-based technologies (protein-binding microarrays; PBMs) provide useful predictions for understanding the transcriptional regulatory code in a genome-wide manner. The PBM was designed in such a way that target probes were synthesized as quadruples of all possible 9-mer combinations, named Q9-UPBM. Also, we developed rice promoter PBM (RPBM) using 19,480 rice promoter sequences containing 40 bp long probe with overlapping 20 bp (cover 1kb from 5’ upstream). We applied RISBZ1 protein, an endosperm specific basic leucine zipper transcription factor, to compare binding site specificities between Q9-UPBM and RPBM and find directly regulated promoter regions through the RPBM. Several cis-elements; Prolamin box (TGTAAAG), GCN4 motif (TGA(G/C)TCA), AACA motif (AACAAAA), and ACGT motif, are highly conserved in the promoters of cereal seed storage protein genes, and play a central role in controlling endosperm specific expression during seed maturation. Characterization of cis-elements and TFs has been performed on many storage protein genes of several crop plants, but the mechanisms are still poorly understood. Two chips provide RISBZ1 could bind to ACGT motif such as a CCACGTCA site and GGATGAC site as well as GCN4 motif known binding site. In RPBM binding affinity to CCACGTCA was highly significant, compared to GGATGAC site. The difference might be caused by the biased presence of specific promoter rather than Q9-UPBM. Also our results will provide direct insight into the importance of combinatorial interplay between cis-elements in regulating the expression of seed storage protein genes.

Thirty-eight glutinous rice varieties were classified into nine groups on the scatter diagram by the upper two principal components (56% contribution to the total information) based on eleven physicochemical characteristics including the viscograms and physical properties of cooked rice. The first principal component was the factor mainly associated with the viscogram characteristics of rice flour emulsion and the second was the factor chiefly related to the physical properties of cooked rice and water absorbability of rice grain. Indica glutinous rices were clearly distinguished from japonica ones by the first principal component score. Javanica glutinous rices were widely distributed on the intermediate zone between indica and japonica or on several japonica rice groups. Significant positive or negative correlations were found among water absorption rates of rice grain, physical properties of cooked rice, and viscogram characteristics of rice flour. Especially in japonica glutinous rices, the breakdown and setback viscosities of rice flour were closely associated with the alkali digestion value of milled rice and the stickiness of cooked rice. The frequency ratio of short glucose chains (A-chain) to intermediate glucose chains (B-chain), the ratio of B- chains to long glucose chains (C-chain) and the relative frequency of A- or B-chain fractions representing the amylopection structure of rice starch was closely associated with the breakdown and setback viscosities of rice flour