Transcriptome and Metabolome Integrated Analysis of Two Ecotypes of Reveals Candidate Genes Involved in Chlorogenic Acid Accumulation.

plants with different geographical origins contain enormous genetic variability, which causes different composition and content of flavonoids. In this research, integrated analysis of transcriptome and metabolome were performed in two ecotypes of . There were 5428 different expressed transcripts and 236 differentially accumulated metabolites, phenylpropane and flavonoid biosynthesis were most predominantly enriched.

Effects of Mutations on Microsatellite Stability and Homeologous Recombination in Rice.

DNA mismatch repair (MMR) system is important for maintaining DNA replication fidelity and genome stability by repairing erroneous deletions, insertions and mis-incorporation of bases. With the aim of deciphering the role of the MMR system in genome stability and recombination in rice, we investigated the function of gene, an import component of the MMR system. To achieve this goal, homeologous recombination and endogenous microsatellite stability were evaluated by using rice mutants carrying a insertion into the gene.

Specific-Locus Amplified Fragment Sequencing Reveals Spontaneous Single-Nucleotide Mutations in Rice Mutants.

Genomic stability depends in part on an efficient DNA lesion recognition and correction by the DNA mismatch repair (MMR) system. We investigated mutations arising spontaneously in rice mutants by specific-locus amplified fragment sequencing. Totally 994 single-nucleotide mutations were identified in three mutants and on average the mutation density is about 1/136.

Frequency and type of inheritable mutations induced by γ rays in rice as revealed by whole genome sequencing.

Mutation breeding is based on the induction of genetic variations; hence knowledge of the frequency and type of induced mutations is of paramount importance for the design and implementation of a mutation breeding program. Although γ ray irradiation has been widely used since the 1960s in the breeding of about 200 economically important plant species, molecular elucidation of its genetic effects has so far been achieved largely by analysis of target genes or genomic regions. In the present study, the whole genomes of six γ-irradiated M rice plants were sequenced; a total of 144-188 million high-quality (Q>20) reads were generated for each M plant, resulting in genome coverage of >45 times for each plant.

Disruption of OsSULTR3;3 reduces phytate and phosphorus concentrations and alters the metabolite profile in rice grains.

Two low phytic acid (lpa) mutants have been developed previously with the aim to improve the nutritional value of rice (Oryza sativa) grains. In the present study, the impacts of lpa mutations on grain composition and underlying molecular mechanisms were investigated. Comparative compositional analyses and metabolite profiling demonstrated that concentrations of both phytic acid (PA) and total phosphorus (P) were significantly reduced in lpa brown rice, accompanied by changes in other metabolites and increased concentrations of nutritionally relevant compounds.

Seed-specific silencing of OsMRP5 reduces seed phytic acid and weight in rice.

Phytic acid (PA) is poorly digested by humans and monogastric animals and negatively affects human/animal nutrition and the environment. Rice mutants with reduced PA content have been developed but are often associated with reduced seed weight and viability, lacking breeding value. In the present study, a new approach was explored to reduce seed PA while attaining competitive yield.

[Genetic transformation of Bt gene into sorghum (Sorghum bicolor L.) mediated by Agrobacterium tumefaciens].

Sorghum (Sorghum bicolor L.) was one of the most important crops in the world next to wheat, rice, maize, soybean and barley. Using the callus derived from immature inflorescence as the recipients, we efficiently transformed sorghum varieties 115, ICS21B and 5-27 with the insecticidal Bacillus thuringiensis (Bt) cry1Ab gene carried in the T-DNA of binary vectors which contained hygromycin resistance gene and gus gene via Agrobacterium tumefaciens.

Transcriptional silencing and developmental reactivation of cry1Ab gene in transgenic rice.

One transgenic rice line lacking Cry1Ab expression product was screened in the progenies of Agrobacterium-transformed transgenic rice variety Zhong 8215 with a cry1Ab gene under field releasing conditions by using GUS histochemical assay and Western blot. Molecular hybridization results revealed that the cry1Ab gene was silenced in the transgenic rice variety Zhong 8215 and two copies of ubiquitin promoter were integrated into the rice genome. The silencing of cry1Ab gene in transgenic rice was found to be due to the methylation of the ubiquitin promoter as revealed by methylation analysis.

[Studies on tea plants (Camellia sinensis) germplasms using EST-SSR marker].

Forty two tea varieties were analyzed by using 16 SSR primer sets derived from tea ESTs in this study, and 13 of the primer sets produced clear bands and 10 of them showed polymorphism, accounting for 76.9%. The PIC (polymorphism information content) for each polymorphic primer set varied from 0.

[Development of EST (Expressed Sequence Tags) Marker in Chinese Cabbage and its Transferability to Repeseed.].

28 pairs of primers were designed according to the expressed sequence tags in Chinese cabbage. After testing on the annealing temperature and the concentration of primer, dNTP and MgCl2, a suitable PCR system was established. Under the condition of reaction system developed, primers designed specific to ESTs were screened against genomic DNA of inbreed line A from which the cDNA library was constructed.

[Studies on the distorted segregation of foreign genes in transgenic rice progenies].

The segregation mode of transgenes was investigated in the transgenic progenies of three rice varieties (lines) produced by Agrobacterium-mediated transformation. The transgenic lines all contained the Bacillus thuringiensis cry1Ab gene, under the control of a maize ubiquitin promoter, and linked in tandem with gusA and hpt genes. PCR analysis showed the transgenes cry1Ab and gusA co-segregated in all self and crossed progenies tested.

[Impact of root exudates from transgenic plants on soil micro-ecosystems].

With the commercialization of transgenic plants, ecological risk assessment of transgenic plants has been scheduled. Many problems such as gene transfer from transgenic plants to related wild species, production of super weeds and super virus, tolerance to insect-resistant transgenic plants, and distruption of biodiversity have been taken place in some transgenic plants. The influences of root exudates from transgenic plants on soil micro-ecosystems were reviewed.