본 연구의 목적은 남한 및 백두산일대 분비나무림의 군집구조를 확인하여 보전 및 관리를 위한 기초자료를 구축하는데 있다. 해발 1,000m 이상의 분비나무림 우점지역을 대상으로 총 470개소의 방형구를 설치하여 임분조사를 실시하였다. 조사시기는 2019년 7월부터 2020년 10월까지 수행되었다. 연구결과 군집은 크게 4개의 군집으로 신갈나무-사스래나무 군집, 분비나무 순군집, 주목 군집 그리고 신갈나무 군집으로 분류되었다. 분비나무 개체군의 흉고직경급은 역 J자형의 임분구조로 분석되었다. 국내 및 백두산 일대까지의 분비나무림의 하층식생은 임분이 안정화됨에 따라 낮은 종다양성지수를 나타낼 것으로 판단되었다. 향후 분비나무림의 쇠퇴지역과 유지지역에 대한 모니터링을 통하여 보전과 이용적 측면을 고려한 산림경영이 필요할 것으로 판단된다.

Porphyromonas gingivalis is among the major etiological pathogens of chronic periodontitis. The virulence mechanisms of P. gingivalis is yet to be identified as its activity is largely unknown in actual disease process. The purpose of this study is to identify antigens of P. gingivalis expressed only in patients with chronic periodontitis using a unique immunoscreening technique. Change Mediated Antigen Technology (CMAT), an antibody-based screening technique, was used to identify virulence-associated proteins of P. gingivalis that are expressed only during infection stage in patients having chronic periodontitis. Out of 13,000 recombinant clones screened, 22 tested positive for reproducible reactivity with rabbit hyperimmune anti-sera prepared against dental plaque samples acquired from periodontitis patients. The DNA sequences of these 18 genes were determined. CMAT-identified protein antigens of P. gingivalis included proteins involved in energy metabolism and biosynthesis, heme and iron binding, drug resistance, specific enzyme activities, and unknown functions. Further analysis of these genes could result in a novel insight into the virulence mechanisms of P. gingivalis.

This study was carried to develop new white cultivars that are suitable export using back cross method of Hypsizygus marmoreus. At first, we did select mother strains(Hm3-8 as brown and Hm0-7 as white) that have excellent cultivational caracteristics and morphology. The two strains are collected spore and selected 150 monokaryon mycelia by dilution method, and then picked out, 10 monokaryon strains, that havn‘t clamp connection and different mycelial morphology on plate. The selected monokaryon mycelia of GPHm3-8 and GPHm0-7 was crossed in PDA plate and the, acquired 100 dikaryon strains as mating rate is 100%. The 100 dikaryon strains is cultivated by sawdust media. And, we are selected 5 strains (BW16, BW41, BW56, BW76, BW96). To practice back cross, we selected 10 monokaryon mycelia that didn't clamp connection from the 5 stains(BW16, BW41, BW56, BW76, BW96). And then, we were carried out back cross with Hm0-7. The mating rate were investigated 31%, 33%, 33%, 34%, and 47% within BW16, BW41, BW56, BW76, and BW96, each other. We obtained 15 hybrid strains as brown line, and 23 hybrid stains as white line among 178 hybrid strains, and picked up 23 white strains because 15 brown strains were not suitable our object to develop new white cultivars among 38 strains. To select the best white strain , cultivated by standard growing condition, and BW76W-13 strain has been selected because it had good quality and morphology, finally. We were carried RAPD to verify difference between mother strains. We confirmed that band pattern of BW76W-13 had different pattern compared with mother strains.

The International Union for the Protection of New Varieties of Plants (UPOV) promotes an effective system of plant variety protection and encourages the development of new varieties of plants. This international convention was initiated to standardize the system efforts and strengthen policy. The establishment of cultivar discrimination system is very important to distinguish varieties between domestic and foreign agricultural products. It is necessary for the protection of breeders’rights. In addition, it will help for more efficient and quality management of plant breeding. This study was conducted to identify and group rice varieties based on agro-morphological characteristics such as plant height, panicle length, number of tillers, culm length, leaf length, leaf width, leaf pigments and flag leaf angles. Using these parameters, statistical analysis classified a total of 243 rice varieties bred in Korea into four groups. Most rice varieties did not exhibit anthocyanin pigments on the leaves particularly on the first leaf, leaf blade, leaf sheath and auricle, except for varieties classified as black rice. Results of phylogenetic and principal component analysis (PCA) indicated that these varieties formed three largely distinct clusters according to their ecotype and morphological differentiation. This result would be useful in rice varietal identification for the protection of breeders’variety rights.

An increasing preference for good eating quality of rice among consumers has become one of the important considerations in rice breeding. Amylose content is a leading factor affecting eating quality of rice. Amylose composition is determined by the relative activity of soluble starch synthase (SSS) and granule-bound starch synthase (GBSS). This study focused on modifying the expression of SSSI gene which is responsible for amylopectin and amylose synthesis in rice by using RNA interference (RNAi) technology. The transgenic rice plants showed various amylose content in rice grains. Favorable rice lines were selected according to genomic PCR, transgene expression and amylose contents analysis. A semi-quantitative RT-PCR was carried out to determine the expression level of SSSI gene after flowering of transgenic rice and wild type. Down-regulation of SSSI gene in transgenic plants was evident in the decreasing expression in rice grains. Accordingly, scanning electron microscopy (SEM) analysis revealed uniform size with smooth curves starch granules in down-regulation rice lines, in contrast with the non-uniform granules in wild type. Results indicated that RNAi-SSSI transgenic lines produced low amylose contents that fell between glutinous and non-glutinous rice. This study showed that down-regulation of endogenous SSSI may improve the eating quality in rice.

The International Union for the Protection of New Varieties of Plants (UPOV) promotes an effective system of plant variety protection and encourages the development of new varieties of plants. International convention was initiated to standardized the system efforts and strengthen the policy. This study was conducted to establish a database for rice identification using morphological characters which include number of tillers and panicle per plant, spikelets per panicle, yield, plant maturity, height, leaf pigments, flag leaf angles, and rice bran. The whole rice population was grouped into three based on leaf angles, majority members of which retained the flag leaf angle-character until maturity stage. Most rice accessions did not exhibit anthocyanin pigments on the leaves particularly on the first leaf, leaf blade, leaf sheath and auricle, except for varieties classified as black rice. In the case of grain, many accessions produced secondary branching, and showed no awn. For agronomic traits, productive tiller and panicle per plant were higher in early flowering varieties, while spikelets per panicle and ripened grain were higher in late flowering varieties, and yield was higher in medium flowering varieties. All data were then pooled for cluster analysis which revealed three major independent clusters and four minor clusters.

Cysteine protease (CP) is one of the well-studied proteolytic enzymes in plants. This class of protease has been implicated in various physiological aspects of developmental stages in plants including seed germination, senescence, and disease immunity. A handful of studies assigned plants cysteine protease in different molecular battlefield under a few selected pathosystems, and initially extricated complex molecular mechanism of resistance. However, its potential use as an agent of resistance to diseases in rice has never been explored. This study demonstrates the function of CP specifically in rice - Xanthomonas oryzae pv. oryzae (Xoo) pathosystem. The CP -encoding full-length cDNA was cloned from Brassica rapa and transformed into japonica rice cv. ‘Gopumbyeo’. The gene was overexpressed under the control of CaMV35S promoter in pFLC vector. Blast analysis of the conserved domain of the gene confirmed its affinity to Peptidase_CIA family. RT-PCR analysis showed that the gene was constitutively expressed in all tissues tested. Regulation of rice resistance through cysteine protease activity is evident in overexpression lines which exhibited an enhanced resistance to four Korean Xoo isolates. Further analyses will be carried out to uncover the specific role of CP in rice-Xoo interaction.

Since global climate changes drastically, pre-harvest sprouting (PHS) is expected to pose serious problems in rice production. CBL-interacting serine/threonine protein kinases (CIPKs) have been implicated to play important role in regulating various abiotic stresses such as cold, salinity and drought. In this study, to understand the function of this gene under pre-harvest sprouting in rice, a cDNA clone encoding CBL-interacting protein kinase 15 was isolated from rice flowers. We constructed a recombinant vector carrying the CIPK15 under the control of the CaMV 35S promoter and Tnos terminator and transformed into rice using Agrobacterium tumefaciens. Insertion of the gene was verified in transformants using HPT resistance test and genomic PCR. Transcriptional profiling using tissues of wild type, Gopum, revealed expression of the gene in whole plant tissues with level of expression highest in the seeds suggesting possible role in dormancy. Comparative expression analysis of the gene in transgenic and wild type through semi-quantitative RT-PCR and real-time PCR showed higher expression in transgenic rice lines. Moreover, screening in the mist chamber showed overexpression lines that were resistant to the PHS. This result suggests the involvement of CIPK15 in the regulation of pre-harvest sprouting.

Low-molecular-weight glutenin subunits (LMW-GS) play a crucial role in the processing quality of wheat flour. They are encoded multi gene family located at the Glu-A3, Glu-B3 and Glu-D3 on the short arm of chromosome 1A, 1B and 1D respectively. Typical LMW-GSs are composed of three parts including a short N-terminal domain, a relatively short repetitive domain and a C-terminal domain. Further, typical LMW-GS sequences are divided into LMW-s, LMW-m and LMW-i types, on the basis of the first amino acid of the mature proteins (serine, methionine and isoleucine, respectively). Although it is known that the allelic variation of LMW-GSs affect the properties of dough, it is still not clear which LMW-GSs confer better bread-making quality because of the larger number of expressed subunits and their overlapping mobility with abundant gliadin proteins. Therefore, it is important to characterize LMW-GS genes and develop functional markers to identify different LMW-GS alleles for application in wheat breeding. In this review, we discuss the various aspects of LMW-GS, including their structural characteristics, the development of marker, relationship between LMW-GSs and bread wheat quality, and genetic engineering of the LMW-GSs.

Secondary plant metabolites undergo several modification reactions, including glycosylation and physiological functions. Glycosylation, which is mediated by UDP-glycosyltransferase (UGT), plays a role in the storage of secondary metabolites and in defending plants against stress. In this study, a UDP-glucosyltransferase cDNA was isolated from Brassica rapa hereinafter referred to as BrUGT. It has a full-length cDNA of 1,236 bp that contains a single open reading frame of 834 bp which encodes a polypeptide of 277 amino acid residues with a calculated mass of 31.19 kDa. BLASTX analysis hits a catalytic domain of glycos_transf_1 super family (c112012) that belongs to the glycosyltransferases group 1 with tetratricopeptide (TPR) regions. UGT gene expression analysis showed high mRNA transcripts in pistil, followed by petal, seed and calyx of flower in Brassica rapa. Furthermore, we constructed a recombinant pFLCIII vector carrying the BrUGT gene under the control of ubiquitin promoter and NOS terminator and transformed into rice using Agrobacterium tumefaciens. The UGT overexpressing rice lines were then characterized at the physiological and molecular levels. To further understand the biological function of BrUGT, transcriptional profiling of the gene in transgenic rice lines under cold, salt, PEG, H2O2, ABA and drought stress condition is underway.

Fortification with vitamins in crops like rice is a continuing endeavor for geneticists and rice breeders. Tryptophan is one of the essential amino acids needed in human diet. In this study, we developed rice mutant lines using ethyl methane sulfonate (EMS) treatment in Korean cv. Donganbyeo and candidate rice lines were selected by insensitivity to the tryptophan analog, 5-methyltryptophan. One of the mutants has a 20-25 fold higher tryptophan level in mature seeds than wild type. To identify the mutations in anthranilate synthase genes, OASA1 and OASA2 sequences were generated. Moreover, mRNA expression levels of tryptophan biosynthesis related genes were examined. To further qualify the tryptophan fortification in rice, comparative assessment of cooking and eating quality was conducted with mutant lines and wild type. The moisture, viscosity, taste quality, protein content, amylose content and amino acid composition were similar with wild type. However, tryptophan contents in the mutant lines were higher than wild type as we targeted. The mutation present in AS gene of 5MT resistant rice may prove useful for the generation of crops with increased tryptophan contents and the mutation differences in AS sequences can be used for selection of mutant lines with high tryptophan level from large population.

There is a great consideration on rice eating quality aside from improving its tolerance to various stresses. High yielding and pest and disease tolerant rice is highly desirable but it is more commercially important if it also has a high eating quality. There are various factors contributing to the good eating quality of rice. This study focuses on modifying the expression of GBSS1 genes which are responsible for amylopectin and amylose synthesis in rice by using RNAi and antisense techniques. We have developed 40 transgenic plants with RNAi-GBSS1 gene and 60 transgenic lines with antisense-GBSS1 gene. The transgenic plants show diverse amylose contents in rice seed. We selected candidate lines according to PCR, RNA expression and amylose contents. A semi-quantitative RT-PCR was carried out to measure the expression level of GBSS1 gene at several time points after the flowering of transgenic plants. The expression level of GBSS1 gene in rice grains decreases over time and the mRNA expression among the transgenic plants were lower compare to its wild type. In the SEM analysis, the starch granule of wild type Gopumbyeo has very large structures accompanied with small ones around the area. However, the starch structures in transgenic plants were smaller and more uniform in size and shape throughout the viewing area

An increasing preference for good eating quality of rice among consumers has become one of the important considerations in rice breeding. Amylose content of starch is one of the important factors of rice eating quality. Amylose composition is determined by the relative activity of soluble starch synthase (SSS) and granule-bound starch synthase (GBSS). This study focuses on modifying the expression of SSS1 gene which is responsible for amylopectin and amylose synthesis in rice by using RNA interference (RNAi) and antisense technology. The transgenic rice plants showed various amylose content (9-17%) in rice seed. Candidate rice lines were selected according to PCR, RNA expression and amylose contents analyses. A semi-quantitative RT-PCR was carried out to determine the expression level of SSS1 gene at several time points after the flowering of transgenic plants. Downregulation of SSS1 gene in transgenic rices was evident in the decreasing expression in rice grains over time. Accordingly, SEM micrographs analysis revealed uniform size with smooth curves starch granules in downregulation rice lines, in contrast with the non-uniform granules in wild type.

Since global climate changes drastically, pre-harvest sprouting (PHS) is expected to pose serious problems in rice production. CBL-interacting serine/threonine protein kinases (CIPKs) have been implicated to play important role in regulating various abiotic stresses such as cold, salinity and drought. In this study, to understand the function of this gene under pre-harvest sprouting in rice, a cDNA clone encoding CBL-interacting protein kinase 15 (CIPK15) was isolated from rice flowers. This gene is 2,818 bp long with 1,332 bp coding region that encodes a polypeptide of 443 amino acids. We constructed a recombinant vector carrying the OsCIPK15 under the control of the CaMV 35S promoter and Tnos terminator and transformed into rice using Agrobacterium tumefaciens. Insertion of the gene was verified in transformants using HPT resistance test and genomic PCR. Transcriptional profiling using tissues of wild type, Gopum, revealed expression of the gene in whole plant tissues with level of expression highest in the seeds suggesting possible role in dormancy. Comparative expression analysis of the gene in transgenic and wild type through semi-quantitative RT-PCR and real-time PCR showed higher expression in transgenic rice lines. Moreover, screening in the mist chamber showed overexpression lines that were resistant to the PHS. This result suggests the involvement of OsCIPK15 in the regulation of pre-harvest sprouting.

In spite of the overwhelming number of cysteine proteases in plants, only a few were substantially investigated. Papain-like cysteine proteases (PLCPs) are commonly implicated to disease immunity in some key pathosystems in plants, such as in tomato – Cladosporium fulvum, potato/tomato – phytopthora infestans, and Arabidopsis – Ralstonia solanacearum, among the few others. This study demonstrates the function of cysteine protease gene cloned form Brassica rapa (BrCP) related to resistance to Xanthomonas oryzae pv. oryzae in transgenic rice lines. The cysteine protease-encoding full-length cDNA was identified and characterized using web-based tools. The gene is 2,267 bp in size with an open reading frame of 1,365 bp that encodes predicted polypeptide of 455 amino acids. Blast analysis of the conserved domain of the gene confirmed its affinity to Peptidase_CIA family. Full-length cDNA of PLCP in Brassica rapa was then cloned and co-overexpressed in rice with HPT marker. Introgression of the gene was confirmed in the transformants through genomic PCR assay. RT-PCR analysis showed that the gene was constitutively expressed and present in all tissues. The overexpression rice lines exhibited an enhanced resistance when screened with four Korean Xoo isolates.

Amylopectin composition is determined by the relative activity of soluble starch synthase (SSS) and granule-bound starch synthase (GBSS). Soluble starch synthase and starch branching enzymes are major determinants for the synthesis of amylopectin while GBSS1 is responsible for amylose synthesis in vivo. The formers are made of linear and branched molecules and the latter is composed of highly branched molecules. To increase the palatability of rice, down-regulation of amylose synthesis by antisense and RNA interference (RNAi) could be excellent and powerful tools for controlling the starch composition which is responsible for grain eating quality. The goal of this study is to generate breeding lines with lower amylose content relative to its wild type. This study also reports the results of the two down-regulating technology in lowering the amylose content of rice grain. Furthermore, this study elucidates the effect of using antisense and RNAi for SSS1 and GBSS1.

UDP-glucose 4-epimerase catalyzes the reversible conversion of UDP-glucose to UDP-galactose. The gene, named BrUGE1, isolated from a Chinese cabbage composes of a total length of 1,328 bp that contains a single open reading frame (ORF) of 1,056 bp which encodes a polypeptide of 351 amino acid residues with a calculated mass of 39.0 kDa. Expression analysis showed that BrUGE1 is tissue specific and highly expressed in stem of rice plant. Interestingly, BrUGE1 mRNA was highly accumulated by drought stress with significantly higher amount of soluble sugar. Morphological evaluation showed an increase in yield and yield components compared to the wild type. Moreover, a better growth performance on galactose as well as higher UGE1 expression was observed in transgenic rice lines than in wild type. In the Ubi-1::BrUGE1 lines, the increase of UGE1 expression was apparently sufficient to overcome the toxic effects of galactose. Taken together, the Ubi-1::BrGUE1 rice lines increased yield probably by increasing the rate of filled grains. The enhanced drought tolerance may be due to the induction of soluble sugar which may act as osmolyte to compensate dehydration during drought stress.

Bacterial blight is a serious problem of rice in irrigated and rainfed lowlands. It is caused by Xanthomonas oryzae pv. oryzae (Xoo) which is represented by many pathotypes, making it difficult to control. Plant proteases are important players in immunity acting either in the execution of attack, in signaling cascade or in perception of invader. This study demonstrates the response of cysteine protease (CP) upon interaction with the pathogen. The cysteine protease encoding full-length cDNA was identified and characterized using web-based tools. Conserved domain of the gene revealed its affinity to Peptidase_CIA family. The full-length cDNA of CP in Brassica rapa was then cloned and overexpressed in rice. Insertion of gene was verified in the transformants through PCR assay. Spatiotemporal expression of the gene was performed in transgenic rice. To evaluate the resistance of CP-overexpression lines to Xoo, transgenic plants were inoculated with two races of Xoo. In planta analysis of enzymatic activity of CP was also performed before and after infection by the pathogen.

Rice is one of the most important major food crops which provide the major food for more than half of global population. To improve the grain quality as well as grain yield has been the essential breeding goal in rice. The composition of amylopectin is the determinant of rice eating quality under certain threshold of protein content and the ratio of amylose and amylopectin. In this study, RBE 1 driven by CaMV-35S promoter was constructed and transformed using Agrobacterium tumefaciens. We selected single copy with low amylose content among transgenic lines. The mRNA expression was investigated using RT-PCR, and enzyme activity was determined using activity staining method in mid-milky stage endosperm. Also, the overexpression vectors for RBE 1 and SSS 1 driven by seed specific globulin promoter were constructed, respectively. Moreover, the RNA interference vectors for soluble starch synthase 1 and granule bound starch synthase 1 derived by CaMV35S promoter were constructed, respectively and transformed using Agrobacterium tumefaciens. The transgene has been confirmed by amplification of HPT and target gene. The transgenic plants obtained will be used to investigate the gene function of related starch pathway in plant cells using Gopumbyeo as a wild type rice, based on the gain-of-function and the loss-of-function. The development of designed site-specific endonucleases boosted the establishment of gene targeting (GT) techniques in a row of different species. However, the methods described in plants require a highly efficient transformation and regeneration procedure and, therefore, can be applied to very few species. Here, we describe a highly efficient GT system that is suitable for all transformable plants regardless of transformation efficiency. Efficient in planta GT was achieved in rice by expression of a site specific endonuclease (SSS1::ZFN) that not only cuts within the target but also the chromosomal transgenic donor, leading to an excised targeting vector.