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Soo Jin Kwon

Bio: Soo Jin Kwon is an academic researcher from Rural Development Administration. The author has contributed to research in topics: Genome & Brassica rapa. The author has an hindex of 6, co-authored 7 publications receiving 547 citations.

Papers
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Journal ArticleDOI
TL;DR: It appears that polyploidy and chromosomal diploidization are ongoing processes that collectively stabilize the B. rapa genome and facilitate its evolution.
Abstract: Brassica rapa is one of the most economically important vegetable crops worldwide. Owing to its agronomic importance and phylogenetic position, B. rapa provides a crucial reference to understand polyploidy-related crop genome evolution. The high degree of sequence identity and remarkably conserved genome structure between Arabidopsis and Brassica genomes enables comparative tiling sequencing using Arabidopsis sequences as references to select the counterpart regions in B. rapa, which is a strong challenge of structural and comparative crop genomics. We assembled 65.8 megabase-pairs of non-redundant euchromatic sequence of B. rapa and compared this sequence to the Arabidopsis genome to investigate chromosomal relationships, macrosynteny blocks, and microsynteny within blocks. The triplicated B. rapa genome contains only approximately twice the number of genes as in Arabidopsis because of genome shrinkage. Genome comparisons suggest that B. rapa has a distinct organization of ancestral genome blocks as a result of recent whole genome triplication followed by a unique diploidization process. A lack of the most recent whole genome duplication (3R) event in the B. rapa genome, atypical of other Brassica genomes, may account for the emergence of B. rapa from the Brassica progenitor around 8 million years ago. This work demonstrates the potential of using comparative tiling sequencing for genome analysis of crop species. Based on a comparative analysis of the B. rapa sequences and the Arabidopsis genome, it appears that polyploidy and chromosomal diploidization are ongoing processes that collectively stabilize the B. rapa genome and facilitate its evolution.

201 citations

Journal ArticleDOI
TL;DR: The considerable variation that the authors observed, even between the different versions of the same Brassica genome, for gene fragments and annotated putative genes suggest that the concept of the pan-genome might be particularly appropriate when considering Brassica genomes.
Abstract: Homoeologous regions of Brassica genomes were analyzed at the sequence level. These represent segments of the Brassica A genome as found in Brassica rapa and Brassica napus and the corresponding segments of the Brassica C genome as found in Brassica oleracea and B. napus. Analysis of synonymous base substitution rates within modeled genes revealed a relatively broad range of times (0.12 to 1.37 million years ago) since the divergence of orthologous genome segments as represented in B. napus and the diploid species. Similar, and consistent, ranges were also identified for single nucleotide polymorphism and insertion-deletion variation. Genes conserved across the Brassica genomes and the homoeologous segments of the genome of Arabidopsis thaliana showed almost perfect collinearity. Numerous examples of apparent transduplication of gene fragments, as previously reported in B. oleracea, were observed in B. rapa and B. napus, indicating that this phenomenon is widespread in Brassica species. In the majority of the regions studied, the C genome segments were expanded in size relative to their A genome counterparts. The considerable variation that we observed, even between the different versions of the same Brassica genome, for gene fragments and annotated putative genes suggest that the concept of the pan-genome might be particularly appropriate when considering Brassica genomes.

177 citations

Journal ArticleDOI
TL;DR: The results suggest that the BrFLC genes act similarly to AtFLC, a technique for controlling flowering time in Chinese cabbage and other crops to produce high yields of vegetative tissues.
Abstract: Chinese cabbage plants remain in the vegetative growth phase until they have experienced prolonged exposure to cold temperature, known as vernalization. This inhibition of flowering is caused by the high levels of FLOWERING LOCUS C (FLC) expression. To increase the product value of Chinese cabbage by inhibiting the floral transition, three genes (BrFLC1, BrFLC2, and BrFLC3) homologous to the AtFLC gene, which encodes a floral repressor, were isolated from the Chinese cabbage ‘Chiifu’. These genes showed high similarity to AtFLC, although the putative BrFLC1 protein contained ten more residues than AtFLC. The BrFLC genes were expressed ubiquitously, except that BrFLC3 was not expressed in roots. BrFLC1 and BrFLC2 showed stronger expression than BrFLC3 in unvernalized and vernalized Chinese cabbage. The expression levels of the three BrFLC genes were lower in an early-flowering Chinese cabbage, suggesting that the BrFLC transcript level was associated with flowering time. Constitutive expression of the BrFLC genes in Arabidopsis significantly delayed flowering, which was also observed in transgenic Chinese cabbage overexpressing BrFLC3. These results suggest that the BrFLC genes act similarly to AtFLC. Our results provide a technique for controlling flowering time in Chinese cabbage and other crops to produce high yields of vegetative tissues.

127 citations

Journal ArticleDOI
TL;DR: The near-complete chromosome sequence from a dicotyledonous crop species provides an example of the complexity of genome evolution following polyploidy and provides a benchmark for the performance of whole genome shotgun approaches presently being applied in B. rapa and other species with complex genomes.
Abstract: Background The species Brassica rapa includes important vegetable and oil crops. It also serves as an excellent model system to study polyploidy-related genome evolution because of its paleohexaploid ancestry and its close evolutionary relationships with Arabidopsis thaliana and other Brassica species with larger genomes. Therefore, its genome sequence will be used to accelerate both basic research on genome evolution and applied research across the cultivated Brassica species.

70 citations

Journal ArticleDOI
19 Aug 2014-Rice
TL;DR: Because the Moroberekan alleles for SPP and TGW have been shown to be beneficial in the genetic background of Ilpumbyeo, both the qSPP6 and qTGW6 alleles might prove valuable in improving rice yields.
Abstract: Background: High grain yield is one of the most important traits requiring improvement in rice breeding programs. Consequently, the genetic basis of spikelets per panicle (SPP) and grain weight (TGW) have received much research focus because of their importance in rice yield. Results: In this study, IL28, which is a near isogenic line (NIL) developed by introgressing chromosomal segments of the cultivar ‘Moroberekan’ into the cultivar ‘Ilpumbyeo’, showed a significant increase in the number of spikelets per panicle (SPP) and 1,000-grain weight (TGW) compared to the recurrent parent, Ilpumbyeo. Quantitative trait locus (QTL) analysis in 243 F2 plants derived from a cross between IL28 and Ilpumbyeo indicated that both qSPP6 and qTGW6 are located in the interval RM3430–RM20580. Following substitution mapping with 50 F3:4:5 lines, qSPP6 was mapped to a 429-kb interval between RM20521 and InDel-1, while qTGW6 was mapped to a 37.85-kb interval between InDel-1 and SNP–3 based on the japonica genome sequence. This result indicates that qSPP6 and qTGW6 are different genes. Yield trials with substitution lines indicated that lines harboring the homozygous Moroberekan segment at both the qSPP6 and qTGW6 region showed significantly higher grain yield than Ilpumbyeo. Conclusion: Because the Moroberekan alleles for SPP and TGW have been shown to be beneficial in the genetic background of Ilpumbyeo, both the qSPP6 and qTGW6 alleles might prove valuable in improving rice yields. Closely linked SSR markers are expected to facilitate the cloning of genes that underlie these QTLs, as well as with marker-assisted selection for variation in SPP and TGW in rice breeding programs.

17 citations


Cited by
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Journal ArticleDOI
Xiaowu Wang1, Hanzhong Wang, Jun Wang2, Jun Wang3, Jun Wang4, Rifei Sun, Jian Wu, Shengyi Liu, Yinqi Bai2, Jeong-Hwan Mun5, Ian Bancroft6, Feng Cheng, Sanwen Huang, Xixiang Li, Wei Hua, Junyi Wang2, Xiyin Wang7, Xiyin Wang8, Michael Freeling9, J. Chris Pires10, Andrew H. Paterson8, Boulos Chalhoub, Bo Wang2, Alice Hayward11, Alice Hayward12, Andrew G. Sharpe13, Beom-Seok Park5, Bernd Weisshaar14, Binghang Liu2, Bo Li2, Bo Liu, Chaobo Tong, Chi Song2, Chris Duran11, Chris Duran15, Chunfang Peng2, Geng Chunyu2, Chushin Koh13, Chuyu Lin2, David Edwards11, David Edwards15, Desheng Mu2, Di Shen, Eleni Soumpourou6, Fei Li, Fiona Fraser6, Gavin C. Conant10, Gilles Lassalle16, Graham J.W. King3, Guusje Bonnema17, Haibao Tang9, Haiping Wang, Harry Belcram, Heling Zhou2, Hideki Hirakawa, Hiroshi Abe, Hui Guo8, Hui Wang, Huizhe Jin8, Isobel A. P. Parkin18, Jacqueline Batley12, Jacqueline Batley11, Jeong-Sun Kim5, Jérémy Just, Jianwen Li2, Jiaohui Xu2, Jie Deng, Jin A Kim5, Jingping Li8, Jingyin Yu, Jinling Meng19, Jinpeng Wang7, Jiumeng Min2, Julie Poulain20, Katsunori Hatakeyama, Kui Wu2, Li Wang7, Lu Fang, Martin Trick6, Matthew G. Links18, Meixia Zhao, Mina Jin5, Nirala Ramchiary21, Nizar Drou22, Paul J. Berkman11, Paul J. Berkman15, Qingle Cai2, Quanfei Huang2, Ruiqiang Li2, Satoshi Tabata, Shifeng Cheng2, Shu Zhang2, Shujiang Zhang, Shunmou Huang, Shusei Sato, Silong Sun, Soo-Jin Kwon5, Su-Ryun Choi21, Tae-Ho Lee8, Wei Fan2, Xiang Zhao2, Xu Tan8, Xun Xu2, Yan Wang, Yang Qiu, Ye Yin2, Yingrui Li2, Yongchen Du, Yongcui Liao, Yong Pyo Lim21, Yoshihiro Narusaka, Yupeng Wang7, Zhenyi Wang7, Zhenyu Li2, Zhiwen Wang2, Zhiyong Xiong10, Zhonghua Zhang 
TL;DR: The annotation and analysis of the draft genome sequence of Brassica rapa accession Chiifu-401-42, a Chinese cabbage, and used Arabidopsis thaliana as an outgroup for investigating the consequences of genome triplication, such as structural and functional evolution.
Abstract: We report the annotation and analysis of the draft genome sequence of Brassica rapa accession Chiifu-401-42, a Chinese cabbage. We modeled 41,174 protein coding genes in the B. rapa genome, which has undergone genome triplication. We used Arabidopsis thaliana as an outgroup for investigating the consequences of genome triplication, such as structural and functional evolution. The extent of gene loss (fractionation) among triplicated genome segments varies, with one of the three copies consistently retaining a disproportionately large fraction of the genes expected to have been present in its ancestor. Variation in the number of members of gene families present in the genome may contribute to the remarkable morphological plasticity of Brassica species. The B. rapa genome sequence provides an important resource for studying the evolution of polyploid genomes and underpins the genetic improvement of Brassica oil and vegetable crops.

1,811 citations

Journal ArticleDOI
Boulos Chalhoub1, Shengyi Liu2, Isobel A. P. Parkin3, Haibao Tang4, Haibao Tang5, Xiyin Wang6, Julien Chiquet1, Harry Belcram1, Chaobo Tong2, Birgit Samans7, Margot Correa8, Corinne Da Silva8, Jérémy Just1, Cyril Falentin9, Chu Shin Koh10, Isabelle Le Clainche1, Maria Bernard8, Pascal Bento8, Benjamin Noel8, Karine Labadie8, Adriana Alberti8, Mathieu Charles9, Dominique Arnaud1, Hui Guo6, Christian Daviaud, Salman Alamery11, Kamel Jabbari1, Kamel Jabbari12, Meixia Zhao13, Patrick P. Edger14, Houda Chelaifa1, David C. Tack15, Gilles Lassalle9, Imen Mestiri1, Nicolas Schnel9, Marie-Christine Le Paslier9, Guangyi Fan, Victor Renault16, Philippe E. Bayer11, Agnieszka A. Golicz11, Sahana Manoli11, Tae-Ho Lee6, Vinh Ha Dinh Thi1, Smahane Chalabi1, Qiong Hu2, Chuchuan Fan17, Reece Tollenaere11, Yunhai Lu1, Christophe Battail8, Jinxiong Shen17, Christine Sidebottom10, Xinfa Wang2, Aurélie Canaguier1, Aurélie Chauveau9, Aurélie Bérard9, G. Deniot9, Mei Guan18, Zhongsong Liu18, Fengming Sun, Yong Pyo Lim19, Eric Lyons20, Christopher D. Town4, Ian Bancroft21, Xiaowu Wang, Jinling Meng17, Jianxin Ma13, J. Chris Pires22, Graham J.W. King23, Dominique Brunel9, Régine Delourme9, Michel Renard9, Jean-Marc Aury8, Keith L. Adams15, Jacqueline Batley24, Jacqueline Batley11, Rod J. Snowdon7, Jörg Tost, David Edwards11, David Edwards24, Yongming Zhou17, Wei Hua2, Andrew G. Sharpe10, Andrew H. Paterson6, Chunyun Guan18, Patrick Wincker25, Patrick Wincker8, Patrick Wincker1 
22 Aug 2014-Science
TL;DR: The polyploid genome of Brassica napus, which originated from a recent combination of two distinct genomes approximately 7500 years ago and gave rise to the crops of rape oilseed, is sequenced.
Abstract: Oilseed rape (Brassica napus L.) was formed ~7500 years ago by hybridization between B. rapa and B. oleracea, followed by chromosome doubling, a process known as allopolyploidy. Together with more ancient polyploidizations, this conferred an aggregate 72× genome multiplication since the origin of angiosperms and high gene content. We examined the B. napus genome and the consequences of its recent duplication. The constituent An and Cn subgenomes are engaged in subtle structural, functional, and epigenetic cross-talk, with abundant homeologous exchanges. Incipient gene loss and expression divergence have begun. Selection in B. napus oilseed types has accelerated the loss of glucosinolate genes, while preserving expansion of oil biosynthesis genes. These processes provide insights into allopolyploid evolution and its relationship with crop domestication and improvement.

1,743 citations

10 Dec 2007
TL;DR: The experiments on both rice and human genome sequences demonstrate that EVM produces automated gene structure annotation approaching the quality of manual curation.
Abstract: EVidenceModeler (EVM) is presented as an automated eukaryotic gene structure annotation tool that reports eukaryotic gene structures as a weighted consensus of all available evidence. EVM, when combined with the Program to Assemble Spliced Alignments (PASA), yields a comprehensive, configurable annotation system that predicts protein-coding genes and alternatively spliced isoforms. Our experiments on both rice and human genome sequences demonstrate that EVM produces automated gene structure annotation approaching the quality of manual curation.

1,528 citations

Journal ArticleDOI
29 Nov 2012-Nature
TL;DR: It is shown that the hexaploid genome is highly dynamic, with significant loss of gene family members on polyploidization and domestication, and an abundance of gene fragments.
Abstract: Bread wheat (Triticum aestivum) is a globally important crop, accounting for 20 per cent of the calories consumed by humans. Major efforts are underway worldwide to increase wheat production by extending genetic diversity and analysing key traits, and genomic resources can accelerate progress. But so far the very large size and polyploid complexity of the bread wheat genome have been substantial barriers to genome analysis. Here we report the sequencing of its large, 17-gigabase-pair, hexaploid genome using 454 pyrosequencing, and comparison of this with the sequences of diploid ancestral and progenitor genomes. We identified between 94,000 and 96,000 genes, and assigned two-thirds to the three component genomes (A, B and D) of hexaploid wheat. High-resolution synteny maps identified many small disruptions to conserved gene order. We show that the hexaploid genome is highly dynamic, with significant loss of gene family members on polyploidization and domestication, and an abundance of gene fragments. Several classes of genes involved in energy harvesting, metabolism and growth are among expanded gene families that could be associated with crop productivity. Our analyses, coupled with the identification of extensive genetic variation, provide a resource for accelerating gene discovery and improving this major crop.

1,017 citations

Journal ArticleDOI
TL;DR: A draft genome sequence of Brassica oleracea is described, comparing it with that of its sister species B. rapa to reveal numerous chromosome rearrangements and asymmetrical gene loss in duplicated genomic blocks.
Abstract: Polyploidization has provided much genetic variation for plant adaptive evolution, but the mechanisms by which the molecular evolution of polyploid genomes establishes genetic architecture underlying species differentiation are unclear Brassica is an ideal model to increase knowledge of polyploid evolution Here we describe a draft genome sequence of Brassica oleracea, comparing it with that of its sister species B rapa to reveal numerous chromosome rearrangements and asymmetrical gene loss in duplicated genomic blocks, asymmetrical amplification of transposable elements, differential gene co-retention for specific pathways and variation in gene expression, including alternative splicing, among a large number of paralogous and orthologous genes Genes related to the production of anticancer phytochemicals and morphological variations illustrate consequences of genome duplication and gene divergence, imparting biochemical and morphological variation to B oleracea This study provides insights into Brassica genome evolution and will underpin research into the many important crops in this genus

884 citations