• Plant Biotechnology Reports
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• v.5 no.4
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• pp.309-315
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• 2011

Rice grown in anaerobic waterlogged soil accumulates ammonium as a major source of nitrogen (N). We have compared the physiological symptoms of rice seedlings subjected to N-starvation stress with those receiving sufficient N, based on measurements of shoot/root length and weight and an analysis of protein expression patterns. N starvation marginally increased root growth but notably decreased shoot biomass. N uptake was reduced by >50% in the roots and shoots of N-starved seedlings. To better understand the mechanism of N starvation in rice, we performed a comparative proteome analysis of proteins isolated from rice leaves. Twenty-five differentially expressed proteins were analyzed by matrixassisted laser desorption/ionization time-of-flight (TOF) mass spectrometry and electron spray ionization quadrupole TOF. Functional analysis of the N-starvation response proteins suggested their involvement in protein synthesis and fate, metabolism, and defense. These results indicate that these proteins may play important roles in regulating the plant's complex adaptation responses for N use during N starvation. The proteins may be useful for further characterization of protein function in plant N nutrition.

• Journal of Crop Science and Biotechnology
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• v.11 no.4
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• pp.227-232
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• 2008

Drought stress is one of the major abiotic stresses in agriculture worldwide. We report here a proteomic approach to investigate the impact of post-fertilization drought on grain quality in rice seed endosperm (Oryza sativa cv. IR-64). Plants were stressed for 4 days at 3 days before heading. Total proteins of endosperm were extracted and separated by two-dimensional gel electrophoresis. Not many protein spots showed differential accumulation in drought-stressed samples. More than 400 protein spots were reproducibly detected, including three that were up-regulated and five down-regulated. Mass spectrometry analysis and database searching helped us to identify six spots representing different proteins. Functionally, the identified proteins were related to protein synthesis and carbohydrate metabolism, such as Granule-Bound Starch Synthase (GBSS, Wx protein), which is thought to play a very important role in starch biosynthesis and quality, a very crucial factor in determining rice grain quality.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.3
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• pp.358-364
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• 2001

The physiochemical properties and interactions between porcine blood and waxy rice were determined. Addition of calcium chloride (0.15%) improved acceptability of blood cake and increased the gelatinization degree of waxy rice. The water-holding capacity of porcine blood gel (blood/water=60/40, v/v), extent of absorption and gelatinization of waxy rice, and scanning electron microscopy showed that blood protein matrix and waxy rice are competitors for holding water in the cooking procedure. Non-haem iron content increased linearly (R=0.95) when heating temperature rose. The presence of blood proteins caused increasing of peak temperature (Tp) of gelatinization in differential scanning calorimetric thermal gram, The microstnlcture of plasma proteins and haemoglobin appeared continuous changes, and interacted with surface of waxy rice flour in terms of network and mosaic form, respectively. The electrophoretic patterns revealed an interaction between plasma proteins and waxy rice glutelin and haemoglobin when heated could be found at temperatures above $60^{\circ}C$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.3
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• pp.281-288
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• 2007

Photoperiod sensitive genetic male sterile (PGMS) rice is sterile mutant controlled by photoperiod. A PGMS mutant 920S was sterile grown under long-day (LD) photoperiod (14 h light/10 h dark) but fertile grown under short-day (SD) photoperiod (10 h light/14 h dark). Proteome analysis revealed that 12 protein spots were differentially expressed in the spikelets of 920S plants either treated with LD or SD photoperiod. Among these proteins, three proteins including chlorophyll a/b binding protein, vacuolar ATPase ${\beta}-subunit,\;{\alpha}-tubulin$ and an unknown protein were more than three-fold abundant in the spikelet of the SD-treated plants than those of the LD-treated plants. On the other hand, eight proteins including acetyl transferase, 2, 3- biphosphoglycerate, aminopeptidase N, pyruvate decarboxylase, 60S acidic ribosomal protein and three unknown protein spots were more abundant in the spikelets of the LD-treated plants than those of the SD-treated plants. The results suggest that the observed proteins may be involved in sterile or fertile pollen development under LD or SD photoperiod respectively in the PGMS mutant rice.

• Korean Journal of Breeding Science
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• v.40 no.1
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• pp.1-7
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• 2008

An attempt was made to link rice embryo proteins to DNA sequences and to understand their functions. One hundred of the 700 spots detected on the embryo 2-DE gels were microsequenced. Of these, 28% of the embryo proteins were matched to DNA sequences with known functions, but 72% of the proteins were unknown in functions as previously reported (Woo et al. 2002). In addition, twenty-four protein spots with 100% of homology and nine with over 80% were matched to ESTs (expressed sequence tags) after expanding the amino acid sequences of the protein spots by Database searches using the available rice EST databases at the NCBI (http://www/ncbi.nlm.nih.gov/) and DDBJ (http://www.ddbj.nig.ac.jp/). The chromosomal location of some proteins were also obtained from the rice genetic map provided by Japanese Rice Genome Research Program (http://rgp.dna.affrc.go.jp). The DNA sequence databases including EST have been reported for rice (Oryza sativa L.) now provides whole or partial gene sequence, and recent advances in protein characterization allow the linking proteins to DNA sequences in the functional analysis. This work shows that proteome analysis could be a useful tool strategy to link sequence information and to functional genomics.

• Preventive Nutrition and Food Science
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• v.7 no.4
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• pp.437-441
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• 2002

Rice proteins were extracted from brown and milled rice of five varieties: Kwanganbyeo, Daeanbyeo, Daejinbyeo, Surabyeo, Hwaseongbyeo; and their electrophoretic patterns were analyzed by SDS-PAGE. Albumin was extracted with water, globulin with 5% NaCl, prolamin with 70% ethanol, and glutelin with 0.2 M sodium borate buffer (pH 10.0) containing 0.5% SDS, 0.6% $\beta$-mercaptoethanol. The ratios of albumin : globulin : prolamin : glutelin in the brown rice were 10.8~14.1 : 12.4~16.4 : 3.6~5.3 : 68.6~72.8, and in milled rice were 4.4~5.6 : 10.6~12.0 : 3.9~5.4 : 75.7~79.8. In albumin seven major bands were observed with molecular weights ranging from 14.g~96.8 kDa, in globulin four bands with molecular weights in the range of 14.4~56.9 kDa, prolamin had only one band with a molecular weight of 14.4 kDa, and glutelin had four bands with molecular weights of 14.4 ~ 57.4 kDa. There were no differences in electrophoretic patterns between rice varieties or between brown and milled rice.

• Food Science and Industry
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• v.52 no.1
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• pp.60-67
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• 2019

Protein is a major nutrient of food and has long been studied for nutritional and utility value. Among them, rice protein is attracting attention because of its hypoallergenic characteristics and nutritional value. Rice proteins are divided into endosperm protein and bran protein depending on their location. The two proteins differ in their nutritional characteristics and applications. The endosperm protein is an insoluble protein and has an advantage of digestion and absorption. Rice bran protein dissolves well in water. Its amino acid value is high enough to be comparable to that of soy protein, and it has strong antioxidant ability. Rice protein is a healthy vegetable protein because of its health and hypoallergenic properties. It has been widely used in children's or patients' food, and recently for muscle supplement and health food. Rice protein is considered to be a very effective and useful material as it has been discovered so far.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.1
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• pp.66-72
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• 2006

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.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.92-102
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• 2006

Abundant proteins often cause problems in proteome study. Glutelin family proteins (hereafter referred to glutelin) are present in rice proteome sample as over-whelming constituents with very high abundance. In order to increase the number of identified proteins in rice proteome study, we developed a newly improved method for sample preparation through the removal of glutelin. When the protein samples from rice seed were extracted by the conventional trichloroacetic acid (TCA) extraction method, glutelin accounts for about 60% of total rice seed proteins in SDS gels. Using our new water extraction method, glutelin consists of only about 10% of total proteins. After analyzing on a two-dimensional gel electrophoresis (2-DE), 937 protein spots were detected using the conventional TCA extraction method. On the other hand, 1240 proteins could be seen using the new water extraction method. The selectivity for non-glutelin and less abundant protein by the water extraction method was also confirmed by ESI-Q/TOF mass spectrometry analysis. Thus, the new water extraction method developed here can be efficiently used to study the proteome analysis of rice storage seed.

• Plant Biotechnology Reports
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• v.3 no.2
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• pp.167-174
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• 2009

To identify genes involved in rice Pi5-mediated disease resistance to Magnaporthe oryzae, we compared the proteomes of the RIL260 rice strain carrying the Pi5 resistance gene with its susceptible mutants M5465 and M7023. Proteins were extracted from the leaf tissues of both RIL260 and the mutant lines at 0, 24, and 48 h after M. oryzae inoculation and separated by two-dimensional polyacrylamide gel electrophoresis (2-DE). Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis identified eight proteins that were differently expressed between the resistant and susceptible plants (three down- and five up-regulated proteins in the mutants). The down-regulated proteins included a triosephosphate isomerase (spot no. 2210), a 2,3-bisphosphoglycerate-independent phosphoglycerate mutase (no. 3611), and an unknown protein (no. 4505). In addition, the five up-regulated proteins in the mutants were predicted to be a fructokinase I (no. 313), a glutathione S-transferase (no. 2310), an atpB of chloroplast ATP synthase (no. 3616), an aminopeptidase N (no. 3724), and an unknown protein (no. 308). These results suggest that proteomic analysis of rice susceptible mutants is a useful method for identifying novel proteins involved in resistance to the M. oryzae pathogen.