Glutamine synthetase (GS) plays important roles in plants like assimilation of ammonium and detoxification of the ammonium released from many metabolic processes such as amino acid degradation or photorespiration. Using ATP, ammonia is combined with glutamate to yield glutamine by the action of GS. Phosphinothricin (PPT) is widely used as a herbicide because it competes with glutamate to bind the active site of GS. PPT has been used to produce transgenic Brachypodium distachyon callus and plants as a selectable agent. PPT treatment raises ammonium content and induces toxicity in non-transformed cells. To find out efficient condition for selecting transformed callus, ammonium content were measured in this study. Non-transformed callus were derived from mature seeds of Brachypodium distachyon (Bd21). The callus were cultured on the callus inducing media (CIM) or regeneration media (RM) containing serial dilutions of the PPT (2, 5, 10 and 15 mg/l) with or without light. Ammonium content was measured 2 weeks after PPT application. Ammonium toxicity associated with PPT treatment was dose-dependent on RM whereas PPT treatment was not significantly influenced on CIM. There is no influence on dark or light condition. Additionally, callus were cultured on the media containing phytohormones combined with PPT (5 mg/l) and the most affecting element causing increased ammonium content has been identified. Acknowledgements: This work was supported by a grant (No. 20070301-034-016-007) from BioGreen 21 Program, RDA, Republic of Korea.

Rye (Secale cereale L.) chromatins have been used to introduce agronomically important traits into wheat (Triticum aestivum L.). Wheat-rye translocations in the form of 1RS.1AL, 1RS.1BL, 2BS.2RL have been developed for an important genetic source of disease and pest resistance. The long arm of rye chromosome 2 (2RL) has valuable genes that confer resistance to pests such as biotype L of Hessian fly, powdery mildew, leaf and stem rust. Here, we report the generation and analysis of expressed sequence tags from Hessian fly infested wheat-rye translocation. RNAs were isolated from young seedlings infested by Hessian fly. cDNA library was constructed using Clontech cDNA library construction kit. Random sequencing of candidate clones were performed. The EST clones might be useful to clone target gene sequences and would provide clues on molecular interaction between wheat and Hessian fly.

barley grain and malt is highly related to beer quality, especially hordein is known to be a more significant factor in malting process than albumin. In this study, we proposed selection criteria for high quality malting barley with aid of grain and malt quality parameter scores and storage protein subunit profile informations. Albumin and hordein were extracted and denatured protein subunits were evaluated with malt and grain quality parameters. Total 13 local adaptability test (LAT) lines were planted in four locations (Naju, Iksan, Jeju, and Jinju) and evaluated for malt and beer making qualities. Seventeen germplasms (world collections for high or low seed storage protein content) were also evaluated for biochemical genetic marker. Denatured seed storage protein subunits of albumin and hordein of all tested lines and germplasms were evaluated using 12% 1D SDS-PAGE. Scored data of protein subunit's presence or absence was applied to Agglomerative Hierarchical Clustering (AHC) for statistical analysis. Subunits fractionated within specific molecular weight ranges (97.4-31.0, 66.2-31.0, and 45.0-31.0 kDa) were highly correlated with agricultural characteristics. Several LAT lines showing good performance in agricultural characteristics were clustered in dendrogram constructed by biochemical-genetic assay using XLSTAT. Specific band pattern showed in good performance LAT lines were also observed in some germplasms of world collection having low protein contents which are known to have superior quality in malting. The results would provide selection criteria for high quality malting barley in the malting barley breeding program.

UNUSUAL FLORAL ORGAN (UFO), a novel gene, is involved in controlling flowering initiation and development. In Arabidopsis, UFO is required for floral organ identity in the second and third whorls. However, the mode of expression and function of TaUFO have not been studied yet. The cDNA sequence of TaUFO is comprised of 1344 bp open reading frame which encodes 50.82 KDa polypeptide consisting amino acid residues. F-box protein, the components of TaUFO, plays an important regulatory role in a wide diversity of developmental and physiological responses. In almost all F box proteins, the N terminus of the protein contains the F-box motif, and the rest of the protein contains the protein-protein interaction domains required for target protein binding. In order to elucidate the function of the TaUFO, various phytohormones and abiotic stresses were applied on young seedlings (14 day after germination) and its transcripts were evaluated. TaUFO:GFP fusion construct was transformed into onion epidermal cells by particle bombardment to elucidate the subcellular localization of the TaUFO protein. The function of the F-box protein is to interact with target proteins. With the use of a yeast two-hybrid screen to isolate proteins interacting with the TaUFO (F box protein), we identified potential TaUFO interactive protein in wheat spikelet library.

Seed storage proteins of different solubility were extracted and denatured subunits of each protein were evaluated with malting barley quality parameters. Its been known that each subunit of seed storage protein encoded by each gene and subunit profiles were highly related to end-use quality in cereals. The purpose of this study is to provide selection criteria for high quality malting barleys with aid of bichemical-genetic information. Total 13 regional test lines and three locations (Naju, Jinju, and Jeju) were incorporated in this study. Albumin and hordein were extracted, denatured, and separated in 12% SDS-PAGE. Presence and absence of subunits of each protein were scored. Dendrogram (using XLSTAT program) was constructed to evaluated the relatedness of lines. The correlation between band profiles and quality test were assessed through Agglomerative Hierarchical Clustering (AHC) for statistics analysis. Hordein subunits can be classified into four groups, A, B, C, and D group. In general, hordein fractions contribute higher than albumine to determine malting quality. Specific molecular weight ranges (97.4-31.0, 66.2-31.0, and 45.0-31.0 kDa) of subunits were highly correlated with malting barley quality parameters. The subunit information would be directly incorporated in providing selection criteria for high quality malting barley in the malting barley breeding program.

Pectin, one of the main components of plant cell wall, is deesterified in muro by PME (Pectin methylesterase). PME activity is particularly regulated by inhibitor proteins known as the pectin methylesterase inhibitor (PMEI). The PMEI plays a key role in wounding, osmotic stress, senescence and seed development. However, the role of PMEI in plant species still remains to be demonstrated especially in wheat. To facilitate the studies on the expression of the TaPMEI gene, RT-PCR was performed using leaf, stem and root tissues in response to exogeneous application of phytohormones and abiotic stress treatments. Transcription of the TaPMEI gene was significantly induced in NaCl, H2O2 and SA treatments, and reduced when plants were treated with ABA. To elucidate the subcellular localization of the TaPMEI protein, TaPMEI:GFP fusion construct was transformed into onion epidermal cells by particle bombardment. The fluorescence signal was exclusively detected in cell wall of the cells. In order to obtain recombinant TaPMEI protein, the TaPMEI protein, expressed in E.coli as a MBP (~42.5 kDa) fusion protein recombinant. Purification and functinal analysis of TaPMEI as an inhibitor of PME activity are described.

Most vacuolar proteins are synthesized on the endoplasmic reticulum (ER) as a proprotein precursor and then transported to vacuoles. In vacuoles, they are converted into the respective mature form. TaVPE1 and TaVPE2 were isolated from the cDNA library that was prepared from the wheat kernels at 16 and 18 days after fertilization (DAF). Additionally, putative TaVPEs (TaVPE3, TaVPE4) were isolated by inverse PCR (IPCR) using GrainGenes database. Each open reading frame (ORF) encodes 495, 497, 495, 456 amino acids, respectively. TaVPEs were closely related in respect to peptide comparisons and their sequence homologies were ranged from 84% to 93%. The TaVPE genes showed various expression patterns in response to exogenous treatment of phytohormones. The transcript of TaVPE1 was detected slightly and steadily after exposure to all phytohormones and the accumulation of TaVPE2 transcript was increased from 24 hours in NaCl treatment. The transcript of TaVPE3 was increased from 48 hours in response to H2O2 and decreased after exogenous application of ABA and salicylic acid. In case of TaVPE4, the transcript of TaVPE4 were weakly detected all time points of each phytohormone treatment.

It was previously pointed out that mutation is the ultimate source of variation. Adequate variation is needed for plant breeding if there is a limitation in natural genetic resources. When the ionizing radiation has been known to cause chromosomal and genomic alternations, it is widely used for inducing mutagenesis. The electron beam as an ionizing radiation is the principal physical mutagens that induces mutation and effectively used in plant breeding. Since dose-response relationships of electron beam in plant species are rarely known, we investigated the seed germination rate and early seedling growth of irradiated seeds of creeping bentgrass (Agrostis palustris Huds., cv Penn-A1) with various electron beam irradiating conditions (1, 1.3, 2 MeV at both 0.03 mA and 0.06 mA with dose of 100 Gy (Gray) and 0.03, 1, 1.3, 2 MeV at 0.03 mA with dose of 200 Gy, respectively) using electron accelerator at Korea Atomic Energy Research Institute. The growth parameters in terms of shoot length, primary root length, and secondary root length showed similar response between 0.06 / 1 (mA / MeV) at 100 Gy and 0.03 / 0.3 (mA / MeV) at 200 Gy. Bentgrass seed germination was mainly affected by the intensity of irradiated dose (Gray). Germination rate was lowered as the irradiated dose increased. On the other hand, early seedling growth was mainly governed not by the dose of radiation but by voltage.