<i>Ac/Ds</i> -induced chromosomal rearrangements in rice genomes

Xuan, Yuan Hu,Zhang, Jianbo,Peterson, Thomas,Han, Chang-deok Landes Bioscience 2012 Mobile genetic elements Vol.2 No.2

<P>A closely-linked pair of <I>Ac/Ds</I> elements induces chromosomal rearrangements in Arabidopsis and maize. This report summarizes the <I>Ac</I>/<I>Ds</I> systems that generate an exceptionally high frequency of chromosomal rearrangements in rice genomes. From a line containing a single <I>Ds</I> element inserted at the <I>OsRLG5</I> locus, plants containing a closely-linked pair of inversely-oriented <I>Ds</I> elements were obtained at 1% frequency among the population regenerated from tissue culture. Subsequent regeneration of the lines containing <I>cis</I>-paired <I>Ds</I> elements via tissue culture led to a high frequency (35.6%) of plants containing chromosomal rearrangements at the <I>OsRLG5</I> locus. Thirty-four rearrangement events were characterized, revealing diverse chromosomal aberrations including deletions, inversions and duplications. Many rearrangements could be explained by sister chromatid transposition (SCT) and homologous recombination (HR), events previously demonstrated in Arabidopsis and maize. In addition, novel events were detected and presumably generated via a new alternative transposition mechanism. This mechanism, termed single chromatid transposition (SLCT), resulted in juxtaposed inversions and deletions on the same chromosome. This study demonstrated that the <I>Ac</I>/<I>Ds</I> system coupled with tissue culture-mediated plant regeneration could induce higher frequencies and a greater diversity of chromosomal rearrangements than previously reported. </P><P> Understanding transposon-induced chromosomal rearrangements can provide new insights into the relationship between transposable elements and genome evolution, as well as a means to perform chromosomal engineering for crop improvement. Rice is a staple cereal crop worldwide. Complete genome sequencing and rich genetic resources are great advantages for the study of the genomic complexity induced by transposable elements.<SUP>1</SUP><SUP>–</SUP><SUP>2</SUP> The combination of tissue culture with genetic lines carrying a pair of closely located <I>Ac/Ds</I> elements greatly increases the frequency and diversity of rearrangements in rice genomes. The methodology and its efficiency and significance are briefly summarized.</P>

Transposon <i>Ac/Ds</i> -induced chromosomal rearrangements at the rice <i>OsRLG5</i> locus

Xuan, Yuan Hu,Piao, Hai Long,Je, Byoung Il,Park, Soon Ju,Park, Su Hyun,Huang, Jin,Zhang, Jian Bo,Peterson, Thomas,Han, Chang-deok Oxford University Press 2011 Nucleic acids research Vol.39 No.22

<P>Previous studies have shown that pairs of closely-linked <I>Ac/Ds</I> transposable elements can induce various chromosomal rearrangements in plant genomes. To study chromosomal rearrangements in rice, we isolated a line (<I>OsRLG5-161)</I> that contains two inversely-oriented <I>Ds</I> insertions in <I>OsRLG5</I> (<I>Oryza sativa</I> Receptor like kinase Gene 5). Among approximately 300 plants regenerated from <I>OsRLG5-161</I> heterozygous seeds, 107 contained rearrangements including deletions, duplications and inversions of various sizes. Most rearrangements were induced by previously identified alternative transposition mechanism. Furthermore, we also detected a new class of rearrangements that contain juxtaposed inversions and deletions on the same chromosome. We propose that these novel alleles were generated by a previously unreported type of alternative transposition reactions involving the 5′ and 3′ termini of two inversely-oriented <I>Ds</I> elements located on the same chromatid. Finally, 11% of rearrangements contained inversions resulting from homologous recombination between the two inverted <I>Ds</I> elements in <I>OsRLG5-161</I>. The high frequency inheritance and great variety of rearrangements obtained suggests that the rice regeneration system results in a burst of transposition activity and a relaxation of the controls which normally limit the transposition competence of individual <I>Ds</I> termini. Together, these results demonstrate a greatly enlarged potential of the <I>Ac/Ds</I> system for plant chromosome engineering.</P>

Diverse chromosomal rearrangements induced by Ac/Ds at the OsRLG5 locus in regenerated rice plants

Yuan Hu Xuan,박순주,조준현,김태호,한창덕 한국식물학회 2015 Journal of Plant Biology Vol.58 No.5

Closely-located transposable elements (TEs) can induce chromosomal breakage and rearrangements via alternative transposition (AT) reactions. Our previous study showed that diverse chromosomal rearrangements were induced by two inversely-oriented Ds elements at the OsRLG5 (Oryza sativa receptor-like kinase gene 5) locus in regenerated rice plants. Here, several novel chromosomal rearrangements were identified in a population of tissue culture regenerants, and their proposed Ac/Ds-transposition mechanisms were discussed. In the first type of event, AT was induced by the same Ds element on each of two sister chromatids and resulted in the inversion of genomic DNA flanking the Ds element. In the second type of event, DNA segments of the inter-transposon segment (ITS) region were deleted or inverted. This novel local rearrangement likely resulted from an AT reaction of two directly-oriented Ds elements located on the same chromatid. The 5' and 3' termini of two Ds elements were re-inserted into two different sites inside the ITS, which generated the subsequent deletion and inversion. In the third type of event, two inversely-oriented Ds elements induced homologous recombination and chromosomal translocation. Together, these results showed the diversity of Ac/Ds-mediated chromosomal rearrangements and demonstrated the utility of the experimental system for examining the mechanisms underlying Ac/Ds AT reactions.

Study on Phenotypes and Agronomical utility of a Rice GT1 (grassy tillers 1, OsGT1) Homologue

Vikranth Kumar,Yuan Hu Xuan,Byoung Il Je,Soon Ju Park,Jin Huang,Jing Miao Liu,Ryza A. Priatama,Vimal Raj K,Sung Hoon Kim,Jin-hee Jeong,Chang-deok Han 한국육종학회 2015 한국육종학회 심포지엄 Vol.2015 No.07

Enhancing yield has been a major challenge of agriculture. In rice, tiller number is one of the important biomass and yield components. A maize mutant grassy tillers1 (gt1) increases lateral branches in maize. The GT1 gene encodes a class I homeodomain leucine zipper (HD-Zip) protein. In maize, the gt1 expression is induced by shading and is dependent on the activity of teosinte branched1 (tb1), a major domestication locus controlling tillering and lateral branching. To estimate the biological role and agricultural utility of gt1 in rice, rice homologue (OsGT1) has been isolated and its overexpressors and RNAi lines were generated. Field data showed that OsGT1 overexpressors reduced tillers and panicles while RNAi lines increased them, compared to wild type. Shade signal is an important factor in determining lateral branching. To understand the relationship between OsGT1 and shade avoidance, plants have been grown under 50% shading in the field. Also, double genetic combinations with phytochrome mutants (phyA, B, and C) are being examining for tillering phenotype. These ongoing researches will provide insights in determining the action of OsGT1 on branching and shade avoidance in rice.

Application of Energy Dissipation Technology in High-Rise Buildings

Hu, Da-Zhu,Zhang, Xiao-Xuan,Li, Guo-Qiang,Sun, Fei-Fei,Jin, Hua-Jian Council on Tall Building and Urban Habitat Korea 2021 International journal of high-rise buildings Vol.10 No.2

The principle of energy dissipation technology is to dissipate or absorb the seismic energy input through the deformation or velocity change of dampers installed in the main structure of high-rise buildings, so as to reduce the seismic response of the buildings. With the development of energy dissipation technology, recognized as an effective and new measurement for reducing seismic effects, its application in high-rise buildings has become more and more popular. The appropriate energy dissipation devices suitable for high-rise buildings are introduced in this paper. The effectiveness of energy-dissipation technology for reducing the seismic response of high-rise buildings with various structural forms is demonstrated with a number of actual examples of high-rise buildings equipped with various energy dissipation devices.

MGGC2.0: A preprocessing code for the multi-group cross section of the fast reactor with ultrafine group library

Hu Kui,Ma Xubo,Zhang Teng,Ma Xuan,Huang Zifeng,Chen Yixue 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.8

How to generate the precise broad group cross section is important for the fast reactor design. In this study, a fast reactor multi-group cross-section generation code MGGC2.0 are developed in-house for processing ultrafine group MATXS format library. Validation and verification are performed for MGGC2.0 code by applying the benchmarks of ICSBEP handbook, and the results of MGGC2.0 agree well with that of MCNP. The consistent PN method with critical buckling search is in good agreement that condensed with TWODANT flux and flux moment for the inner core and outer core region. For the radial blanket and reflector, two region approximation method has been applied in MGGC2.0 by using collision Probability Method neutron flux solver. The RBEC-M benchmark was used to verify the power distribution calculation, and the relative error of power distribution comparison with the reference are less than 0.8% in the fuel region and the maximum relative error is 5.58% in the reflector region. Therefore, the precise broad cross section can be generated by MGGC2.0 for fast reactor

Structure Analysis of 16S rDNA Sequences from Strains ofAcidithiobacillus ferrooxidans

Xuan Li,Xueduan Liu,Yuehua Hu,Hong Peng,Yu Yang,Guanzhou Qiu,Jufang Huang 한국생화학분자생물학회 2006 BMB Reports Vol.39 No.2

Developing TCM clinical practice guidelines: A comparison between traditional Chinese medicine and western medicine

Xuan Yu,Shouyuan Wu,Juanjuan Zhang,Yue Hu,Meng Luo,Hongmei Zhao,Xuping Song,Yaolong Chen,Xiaohui Wang 한국한의학연구원 2023 Integrative Medicine Research Vol.12 No.2

Clinical practice guidelines in Traditional Chinese Medicine (CPG-TCM) is the recommendation that aims to provide the best service to users by identifying and summarizing the rules of prevention, diagnosis, treatment, rehabilitation, and regression of diseases based on systematic reviews of evidence and balancing the advantages and disadvantages of different interventions for clinical questions of Traditional Chinese Medicine. Over the past 30 years, the concept and methods of evidence-based medicine have had a significant impact on the development of clinical practice guidelines in Western Medicine (CPG-WM), and their standardized guideline development methods are being adapted and used in the development of CPG-TCM. However, the quality of CPG-TCM is far from CPG-WM, and the methodological system for developing CPG-TCM is not yet fully established. Therefore, this study aims to explore the methodological differences between CPG-TCM and CPG-WM and to inform the development of high-quality CPGTCM.

Vaccination of Brucella abortus recombinant protein DapB induces CD4+/CD8+ T cells differentiation during Brucella abortus infection in BALB/c mice

Tran Xuan Ngoc Huy, Ched Nicole Turbela Aguilar, Trang Thi Nguyen, Said Abdi Salad, Hu Jang Lee, Jin Hur, Dong-Kwan Lee, Suk Kim 한국예방수의학회 2023 예방수의학회지 Vol.47 No.3

Extensive research and testing continue to be conducted for the development of vaccines targeting zoonotic diseases such as brucellosis. In this study, the potential of the DapB as a recombinant protein vaccine to effectively combat Brucella abortus 544 infection in BALB/c mice was evaluated. Western blotting assay results showed that recombinant protein DapB reacted with Brucella-positive serum, indicating its potential immunoreactivity. In vivo results showed that the peripheral blood CD4+ and CD8+ T cell population significantly increased in the DapB-immunized mice group after the first, second and third blood collection, compared to the control group that received PBS. Additionally, at the fourth blood collection, an increase in CD4+ T cell activation was observed in three vaccination groups compared to PBS negative control group. These results indicate the potential of DapB in stimulating cellular immunity. Fourteen days after infection, the bacterial load in the spleen was evaluated. The reduction in bacterial replication in the spleen by both DapB and RB51 highlights their protective efficacy against Brucella infection. These findings contribute to the ongoing efforts in developing effective vaccines against brucellosis and provide valuable insights for further research in this field.

Intracellular Trafficking Modulation by Ginsenoside Rg3 Inhibits Brucella abortus Uptake and Intracellular Survival within RAW 264.7 Cells

( Tran Xuan Ngoc Huy ),( Alisha Wehdnesday Bernardo Reyes ),( Huynh Tan Hop ),( Lauren Togonon Arayan ),( Wongi Min ),( Hu Jang Lee ),( Man Hee Rhee ),( Hong Hee Chang ),( Suk Kim ) 한국미생물 · 생명공학회 2017 Journal of microbiology and biotechnology Vol.27 No.3

Ginsenoside Rg3, a saponin extracted from ginseng, has various pharmacological and biological activities; however, its effects against Brucella infection are still unclear. Herein, the inhibitory effects of ginsenoside Rg3 against intracellular parasitic Brucella infection were evaluated through bacterial infection, adherence assays, and LAMP-1 colocalization, as well as immunoblotting and FACS for detecting MAPK signaling proteins and F-actin polymerization, respectively. The internalization, intracellular growth, and adherence of Brucella abortus in Rg3-treated RAW 264.7 cells were significantly decreased compared with the Rg3-untreated control. Furthermore, an apparent reduction of F-actin content and intensity of F-actin fluorescence in Rg3-treated cells was observed compared with B. abortus-infected cells without treatment by flow cytometry analysis and confocal microscopy, respectively. In addition, treating cells with Rg3 decreased the phosphorylation of MAPK signaling proteins such as ERK 1/2 and p38 compared with untreated cells. Moreover, the colocalization of B. abortuscontaining phagosomes with LAMP-1 was markedly increased in Rg3-treated cells. These findings suggest that ginsenoside Rg3 inhibits B. abortus infection in mammalian cells and can be used as an alternative approach in the treatment of brucellosis.