Nitrogen (N) fertilization is essential for alleviating nutrient deficiencies of the world’s population by increasing rice production, one of the most important food crops of our time. Here we established an in vivo hydroponics rice seedling culture system to investigate the physio-biochemical and molecular responses of various rice genotypes to low nitrogen application. Yoshida’s nutrient solution (YS) was used to grow rice seedlings, and at three-week-old the seedlings manifested highly stable and reproducible symptoms, such as reduced shoot growth and length. Out of 12 genetically selected or tested genotypes, almost all (11 genotypes) showed varied degrees of growth reduction response to applied nitrogen (4 and 40 ppm N for treatment and control, respectively), but SR19663-B-B-34-3-3-3-1 showed similar growth as the control though its leaf width was smaller than the control. The leaves of a 11 representative low nitrogen-responsive genotype as BG90-2 were sampled for revealing the protein profiles between low and normal (control) nitrogen application by using two-dimensional gel electrophoresis (2-DGE) followed by staining of separated proteins with silver. Fifty differentially expressed silver stained protein spots were excised from 2-D gels and 41 proteins identified using high-throughput mass spectrometry (MS) using matrix-assisted laser desorption/ionization-time of flight-MS and nano electrospray ionization liquid chromatography tandem MS. These proteins could be assigned as major (energy metabolism, photosynthesis and oxidative stress) and minor functional categories, revealing many novel low N-responsive proteins, including those having energy/photosynthesis, and defense/stress, and iron homeostasis-related functions.

본 연구는 벼종자 미량 단백질의 프로테오믹스 연구를 위하여 벼종자에 고 함량으로 존재하는 벼종자 글루테린 저장 단백질을 제거하는 방법에 관한 것이다. 따라서 본 연구는, (A) 벼종자에 액체 질소를 가하고 분쇄하여 벼종자 가루를 만드는 분쇄단계; (B) 상기 분쇄된 벼종자 가루를 물에 현탁하여 현탁액을 만드는 현탁단계; (C)상기 현탁액 중 미용해 물질을 제거하는 분리단계를 포함하는, 벼종자 미량 단백질의 프로테오믹스 연구를 위한 벼종자 글루테린 저장 단백질의 제거방법에 관하여 검토하였다. 본 연구의 결과, 단순하고 신속하며 저렴하고 효율적인 방법으로 미량 비글루테린 단백질들을 용이하게 동정할 수 있을 것으로 판단되었다.

Spikelet proteins expressed at the young microspore stage in rice were separated and analysed by two-dimensional polyacrylamide gel electrophoresis (2DE). The separated proteins were electro blotted onto a polyvinylidene difluoride (PVDF) membrane, and 50 proteins were analyzed by a gas-phase protein sequencer. The N-terminal amino acid sequences of 20 out of 50 proteins were determined. N-terminal regions of the remaining proteins could not be sequenced because of blocking. The internal amino acid sequences of proteins were determined by sequence analysis of peptides obtained by the Cleveland peptide mapping method. Results revealed the presence of the photosynthetic apparatus at rice young microspore stage. Major proteins identified in this study could be used as a marker for various studies on physiological stresses.

Seed proteins of allogamous buckwheat (Fagopyrum esculentum Moench. cv. Miyazakizairai) and autogamous buck-wheat were separated by two-dimensional gel electrophoresis (2-DE) and characterized by gasphase sequencing. Total of 100 pro-could be used as mark

In this study, we present different physiological responses to cold acclimation between the freezing tolerant barley landrace, Jeonnamjaerae, and the freezing sensitive line, PI283398, chosen by the previous field test. We tried to identify some key facto

Antifreeze proteins (AFPs) accumulate in the leaves of barley during cold acclimation, where they may inhibit ice recrystallization and produce freezing resistance of the plant. Four parental diallel crosses of the barley varieties were used to determine the heritability of AFPs and the relationship between the accumulation level of AFPs and freezing resistance. The concentration of apoplastic proteins in the cold-acclimated leaves was increased in the mean by four-fold over as compared with that of nonacclimated. The diallel cross analyses revealed that the gene of Sacheon 6 was dominant and those of Reno and Dongbori 1 were recessive. The AFPs had high narrow-sense heritabilities. The general combining ability effects of Reno and Dongbori 1 were much higher than the other parents. The bands of 32-kD for GLP, 35-& 28-kD for CLP and 25-, 22- & 16-kD for TLP were observed in the apoplastic extracts from cold-acclimated plants, but there were no clear differences between the parents and Fl hybrids. The concentrations of AFPs were significantly correlated with the degree of freezing resistance, indicating that the concentration of AFPs in the plant is the very important factor for freezing resistance.

생쥐 신생자 시기에 생식 세포의 사멸 기전을 알아보기 위하여 세포 사멸을 보이는 생식 세포에서 세포 사멸 관련 단백질인 caspase-3, caspase-activated DNase(CAD), Bax 및 Fasnas ligand의 발현을 조사하였다. 활성화된 caspase-3와 CAD의 면역화학적 염색 결과 일차 및 이차 난포내 TUNEL 양성을 보이는 세포 사멸 난자에서 발현되는 것을 관찰하였다. CAD 또한 TUNEL 양성을 보이는 세포 사멸 난자에