Department Of Botany
Permanent URI for this communityhttps://kr.cup.edu.in/handle/32116/28
Browse
6 results
Search Results
Item Transgene-free genome editing supports the role of carotenoid cleavage dioxygenase 4 as a negative regulator of ?-carotene in banana(Oxford University Press, 2022-02-01T00:00:00) Awasthi, Praveen; Khan, Shahirina; Lakhani, Hiralben; Chaturvedi, Siddhant; Shivani, S.; Kaur, Navneet; Singh, Jagdeep; Kesarwani, Atul Kumar; Tiwari, SiddharthCarotenoid cleavage dioxygenases (CCDs) belong to a small gene family and have an important role in the intricate metabolism of carotenoids in plants. In this study we aimed to understand the regulatory mechanism of ?-carotene homeostasis by establishing transgene-free genome editing in banana. We found that the expression patterns of multiple CCDs were correlated with the concentrations of carotenoids in two cultivars with contrasting contents of ?-carotene, Nendran (high) and Rasthali (low). Higher expression of CCD4 in Rasthali (RAS-CCD4) was negatively correlated with ?-carotene accumulation in the fruit-pulp. Docking analysis and enzyme assays of purified RAS-CCD4 suggested that ?-carotene and 10-Apo-?-carotenal were the preferred substrates of RAS-CCD4. Bacterial complementation assays demonstrated the role of RAS-CCD4 in ?-carotene degradation, and this was further confirmed by in vivo overexpression of RAS-CCD4 in Arabidopsis, which resulted in significant reduction in ?-carotene concentration. CRISPR/Cas9-mediated editing of CCD4 was conducted in protoplasts and embryogenic cell lines of Rasthali, and carotenoid profiling in the resulting stable mutant lines showed greater increases in ?-carotene accumulation in the roots than in the leaves compared with unedited controls. The differences in expression of carotenoid pathway genes were correlated with differences in metabolites in the edited lines. Overall, our study suggests that carotenoid catabolism is regulated by CCD4 in ways that are tissue-and cultivar-specific, and it also demonstrates the successful use of the genome-editing tool in developing transgene-free biofortified lines of banana. � 2022 The Author(s) 2022.Item Genetically modified crop regulations: scope and opportunity using the CRISPR-Cas9 genome editing approach(Springer Science and Business Media B.V., 2021-06-10T00:00:00) Gupta, Shweta; Kumar, Adarsh; Patel, Rupali; Kumar, VinayGlobal demand for food is increasing day by day due to an increase in population and shrinkage of the arable land area. To meet this increasing demand, there is a need to develop high-yielding varieties that are nutritionally enriched and tolerant against environmental stresses. Various techniques are developed for improving crop quality such as mutagenesis, intergeneric crosses, and translocation breeding. Later, with the development of genetic engineering, genetically modified crops came up with the transgene insertion approach which helps to withstand adverse conditions. The process or product-focused approaches are used for regulating genetically modified crops with their risk analysis on the environment and public health. However, recent advances in gene-editing technologies have led to a new era of plant breeding by developing techniques including site-directed nucleases, zinc finger nucleases, and the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR associated protein 9 (Cas9) that involve precise gene editing without the transfer of foreign genes. But these techniques always remain in debate for their regulation status and public acceptance. The European countries and New Zealand, consider the gene-edited plants under the category of genetically modified organism (GMO) regulation while the USA frees the gene-edited plants from such type of regulations. Considering them under the category of GMO makes a long and complicated approval process to use them, which would decrease their immediate commercial value. There is a need to develop strong regulatory approaches for emerging technologies that expedite crop research and attract people to adopt these new varieties without hesitation. � 2021, The Author(s), under exclusive licence to Springer Nature B.V.Item Transgene-free genome editing supports the role of carotenoid cleavage dioxygenase 4 as a negative regulator of ?-carotene in banana(Oxford University Press, 2022-02-01T00:00:00) Awasthi, Praveen; Khan, Shahirina; Lakhani, Hiralben; Chaturvedi, Siddhant; Shivani, S.; Kaur, Navneet; Singh, Jagdeep; Kesarwani, Atul Kumar; Tiwari, SiddharthCarotenoid cleavage dioxygenases (CCDs) belong to a small gene family and have an important role in the intricate metabolism of carotenoids in plants. In this study we aimed to understand the regulatory mechanism of ?-carotene homeostasis by establishing transgene-free genome editing in banana. We found that the expression patterns of multiple CCDs were correlated with the concentrations of carotenoids in two cultivars with contrasting contents of ?-carotene, Nendran (high) and Rasthali (low). Higher expression of CCD4 in Rasthali (RAS-CCD4) was negatively correlated with ?-carotene accumulation in the fruit-pulp. Docking analysis and enzyme assays of purified RAS-CCD4 suggested that ?-carotene and 10-Apo-?-carotenal were the preferred substrates of RAS-CCD4. Bacterial complementation assays demonstrated the role of RAS-CCD4 in ?-carotene degradation, and this was further confirmed by in vivo overexpression of RAS-CCD4 in Arabidopsis, which resulted in significant reduction in ?-carotene concentration. CRISPR/Cas9-mediated editing of CCD4 was conducted in protoplasts and embryogenic cell lines of Rasthali, and carotenoid profiling in the resulting stable mutant lines showed greater increases in ?-carotene accumulation in the roots than in the leaves compared with unedited controls. The differences in expression of carotenoid pathway genes were correlated with differences in metabolites in the edited lines. Overall, our study suggests that carotenoid catabolism is regulated by CCD4 in ways that are tissue-and cultivar-specific, and it also demonstrates the successful use of the genome-editing tool in developing transgene-free biofortified lines of banana. � 2022 The Author(s) 2022.Item Genetically modified crop regulations: scope and opportunity using the CRISPR-Cas9 genome editing approach(Springer Science and Business Media B.V., 2021-06-10T00:00:00) Gupta, Shweta; Kumar, Adarsh; Patel, Rupali; Kumar, VinayGlobal demand for food is increasing day by day due to an increase in population and shrinkage of the arable land area. To meet this increasing demand, there is a need to develop high-yielding varieties that are nutritionally enriched and tolerant against environmental stresses. Various techniques are developed for improving crop quality such as mutagenesis, intergeneric crosses, and translocation breeding. Later, with the development of genetic engineering, genetically modified crops came up with the transgene insertion approach which helps to withstand adverse conditions. The process or product-focused approaches are used for regulating genetically modified crops with their risk analysis on the environment and public health. However, recent advances in gene-editing technologies have led to a new era of plant breeding by developing techniques including site-directed nucleases, zinc finger nucleases, and the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR associated protein 9 (Cas9) that involve precise gene editing without the transfer of foreign genes. But these techniques always remain in debate for their regulation status and public acceptance. The European countries and New Zealand, consider the gene-edited plants under the category of genetically modified organism (GMO) regulation while the USA frees the gene-edited plants from such type of regulations. Considering them under the category of GMO makes a long and complicated approval process to use them, which would decrease their immediate commercial value. There is a need to develop strong regulatory approaches for emerging technologies that expedite crop research and attract people to adopt these new varieties without hesitation. � 2021, The Author(s), under exclusive licence to Springer Nature B.V.Item An overview of designing and selection of sgRNAs for precise genome editing by the CRISPR-Cas9 system in plants(Springer, 2019) Uniyal, A.P; Mansotra, K; Yadav, S.K; Kumar, VinayA large number of computational tools have been documented in recent years for identification of target-specific valid single-guide (sg) RNAs (18–20 nucleotide long sequence) that is an important component for the efficient utilization of the CRISPR-Cas9 (clustered regularly interspaced short palindromic repeats—CRISPR-associated Protein) system. Despite optimization of Cas9, other major concerns are on-target efficiency and off-target activity that depend upon the sequence(s) of target-specific sgRNA(s). However, a very little attention has been paid for identification of the best-hit sgRNA for precise targeting as well as minimizing the off-target effects. The aim of this present work is to offer comparative insight into existing CRISPR software tools with their unique features (including targeted genome) and utilities. These available web tools were found to be designed based upon only a few limited mathematical models. Among all these available web tools, three (Benchling, Desktop and CRISPR-P) have been curated as exclusively available for plant genome-editing purpose. These three software tools have been comprehensively described and analyzed with single same target enquiry from two randomly selected genes (IDM2 and IDM3 from Arabidopsis thaliana). Interestingly, all these selected tools generated different results (sgRNAs) even for the same query. In fact, the sequence of sgRNA is considered an important parameter to determine the efficiency and specificity of sgRNAs for precise genome editing. Thus, there is an urgent requirement to pay attention for a validated sgRNA-designing tool for precise DNA editing in plants. In conclusion, this work will encourage building up a consensus for developing a universal valid sgRNA designing for different organisms including plants. © 2019, King Abdulaziz City for Science and Technology.Item The CRISPR–Cas9, genome editing approach: a promising tool for drafting defense strategy against begomoviruses including cotton leaf curl viruses(Springer, 2019) Uniyal, A.P; Yadav, S.K; Kumar, VinayThe CRISPR–Cas9 is emerging genome editing tool and very easy and straightforward in operation that has been tested and explored for introduction of new traits in plant systems. Recently, a number of reports have documented utilization of this technology for providing tolerance against viral diseases mediated by begomoviruses. Begomoviruses infect dicot and are transmitted by white flies and cause devastating losses to yield of important agricultural crops including tomato, cassava and cotton. An overview of genomic structure of begomoviruses has been presented to understand the potential strategy for designing of effective sgRNAs to combat the viral replication for generating resistance against infection. This review provides the introduction, recent developments, and applications of the CRISPR–Cas9 system in plants and proposes a holistic methodology for generating cotton plant an example having resistance against begomoviruses. The genome editing using CRISPR–Cas9 system against complex of begomoviruses collectively termed as cotton leaf curl virus, which a major contributor to reduction of the cotton yield especially in Northern India and Pakistan is also discussed thoroughly. In conclusion, this potential strategy could be a sustainable approach for development of tolerant crops against diseases mediated by DNA viruses. © 2019, Society for Plant Biochemistry and Biotechnology.