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Nasar Uddin Ahmed,Jong-In Park,Ill-Sup Nou 한국육종학회 2015 한국육종학회 심포지엄 Vol.2015 No.07
Anthocyanins are responsible for vivid colors of flowers, fruits and vegetative tissues and biosynthesis of it is primarily controlled by several structural and regulatory genes. The regulatory mechanism of this pathway is still unknown. This study identified 19 transcription factors of Brassica rapa and investigated their regulatory function in anthocyanin biosynthesis pathway genes and cold and/or freezing tolerance in B. rapa. Expression analysis of these genes in the pigmented and non-pigmented portion of leaves of different lines of B. rapa revealed that BrMYB2-2 and BrTT8 showed responses contrasting with anthocyanin accumulation and cold stress. Sequences of these genes were analyzed and compared with similar gene sequences from other species and a high degree of homology with their respective functions was found. Co-regulated cis -elements were found in promoters of BrPAL1, BrCHS, BrF3H1, BrF3’H1, BrFLS, BrBAN, BrDFR8, BrANS1, and BrMYB2-2 and BrTT8 had binding sites of the promoters of those structural genes. Thus, the above results suggest the association of BrMYB2-2 and BrTT8 with regulation of anthocyanin biosynthesis pathway genes and cold and freezing stress tolerance and might be useful resources for development of cold resistant Brassica crops with desirable colors as well.
Progress in Genetic Manipulation of the Brassicaceae
Nasar Uddin Ahmed,박종인,김혜란,노일섭 한국식물생명공학회 2012 식물생명공학회지 Vol.39 No.1
With the increasing advances in Brassicaceae genetics and genomics, considerable progress has been made in the transformation of Brassicaceae. Transformation technologies are now being exploited routinely to determine the gene function and contribute to the development of novel enhanced crops. Agrobacterium-mediated transformation remains the most widely used approach for the introduction of transgenes into Brassicaceae. In Brassica, the transformation relies mainly on in vitro transformation methods. Nevertheless, despite the significant progress made towards enhancing the transformation efficiencies, some genotypes remain recalcitrant to transformation. Advances in our understanding of the genetics behind various transformations have enabled researchers to identify more readily transformable genotypes for use in routine high-throughput systems. These developments have opened up exciting new avenues to exploit model Brassica genotypes as resources for understanding the gene function in complex genomes. Although many other Brassicaceae have served as model species for improving plant transformation systems, this paper summarizes on the recent technologies employed in the transformation of both Arabidopsis and Brassica. The use of transformation technologies for the introduction of desirable traits and a comparative analysis of these as well as their future prospects are also important parts of the current research that is reviewed.
Nasar Uddin Ahmed,Go-Eun Yi,Jong-In Park,Hee-Jeong Jung,Senthil Kumar Thamilarasan,Mi-Young Chung,Ill-Sup Nou 한국육종학회 2014 한국육종학회 심포지엄 Vol.2014 No.07
Flavonoids are divided into several structural classes, including anthocyanins, which provide flower and leaf colors and other derivatives with diverse roles in plant development and interactions with the environment. This study characterized four Anthocyanidin Synthase (ANS) genes of Brassica rapa, a structural gene of anthocyanin biosynthetic pathway, and investigated their association with cold and freezing tolerance in B. rapa. Sequences of these genes were analyzed and compared with similar types of gene sequences of other species and found a high degree of homology with their respective functions. In the organ specific expression analysis, these genes showed expression only in the colored portion of leaves of different lines of B. rapa. On the other hand, BrANS genes also showed differential expression with certain time course of cold stress treatment in B. rapa. Thus, the above results suggest probable association of these genes with anthocyanin biosynthesis and cold and freezing tolerance and might be useful resources for developing cold resistant Brassica crops with desirable colors as well. The present work may help explore the molecular mechanism that regulates anthocyanin biosynthesis and its response to abiotic stress at the transcriptional level in plants.
Nasar Uddin Ahmed,Hee-Jung Kim,Jong-In Park,Hee-Jeong Jung,Senthil Kumar Thamilarasan,Ill-Sup Nou 한국육종학회 2014 한국육종학회 심포지엄 Vol.2014 No.07
Flavonoids including anthocyanins provide flower and leaf colors and other derivatives that play diverse roles in plant development and interactions with the environment and dihydroflavonol 4-reductase (DFR) is part of an important step in the flavonoid biosynthesis pathway of anthocyanins. This study characterized 12 DFR genes of Brassica rapa and investigated their association with anthocyanin coloration, cold and freezing tolerance in several genotypes of B. rapa. Sequences of these genes were analyzed and compared with DFR gene sequences from other species and a high degree of homology was found. Constitutive expression of them in several pigmented and non-pigmented lines of B. rapa showed a correlation with anthocyanin accumulation only for BrDFR8 and 9. Conversely, BrDFR genes also showed responses to cold and freezing stress treatment in B. rapa. BrDFRs were also shown to be regulated by two transcription factors, BrMYB2-2 and BrTT8, contrasting with anthocyanin accumulation and cold and freezing stress. Thus, the above results suggest the association of these genes with anthocyanin biosynthesis and cold and freezing stress tolerance and might be useful resources for development cold and/or freezing resistant Brassica crops with desirable colors as well. The findings presented here may also help explore the molecular mechanism that regulates anthocyanin biosynthesis and its response to abiotic stress at the transcriptional level in plants.
( Nasar Uddin Ahmed ),( Jong In Park ),( Hee Jeong Jung ),( Mi Young Chung ),( Yong Gu Cho ),( Ill Sup Nou ) 한국육종학회 2013 Plant Breeding and Biotechnology Vol.1 No.2
Cabbage (Brassica oleracea) is a very important vegetable worldwide and biotic stress is a crucial issue for this crop. Enhancement of resistance by exploiting stress resistance-related genes offers the most efficient approach to address this issue. Among the stress resistance-related genes, thaumatin-like proteins (TLPs) play a vital role in enhancement of resistance against stresses. In this study, we identified 12 TLPs from B. oleracea genomic DNA sequencing database, analyzed their sequences and compared with other published pathogenesis-related TLPs, and found a high degree of homology with them. In addition, these genes showed an organ-specific expression, three of which expressed differentially after Pectobacterium carotovorum subsp. carotovorum infection in cabbage plants. Data obtained in this study suggest the probable involvement of TLPs in resistance against soft rot disease of Brassica.
Nasar Um Min Allah,Zurairah Berahim,Azlina Ahmad,Thirumulu Ponnuraj Kannan 한국조직공학과 재생의학회 2017 조직공학과 재생의학 Vol.14 No.5
Advancement in cell culture protocols, multidisciplinary research approach, and the need of clinical implication to reconstruct damaged or diseased tissues has led to the establishment of three-dimensional (3D) test systems for regeneration and repair. Regenerative therapies, including dental tissue engineering, have been pursued as a new prospect to repair and rebuild the diseased/lost oral tissues. Interactions between the different cell types, growth factors, and extracellular matrix components involved in angiogenesis are vital in the mechanisms of new vessel formation for tissue regeneration. In vitro pre-vascularization is one of the leading scopes in the tissue-engineering field. Vascularization strategies that are associated with co-culture systems have proved that there is communication between different cell types with mutual beneficial effects in vascularization and tissue regeneration in two-dimensional or 3D cultures. Endothelial cells with different cell populations, including osteoblasts, smooth muscle cells, and fibroblasts in a co-culture have shown their ability to advocate pre-vascularization. In this review, a co-culture perspective of human gingival fibroblasts and vascular endothelial cells is discussed with the main focus on vascularization and future perspective of this model in regeneration and repair.