China
Africa
Explore chapters and articles related to this topic
Genome Editing Tools
Published in Vineet Kumar, Vinod Kumar Garg, Sunil Kumar, Jayanta Kumar Biswas, Omics for Environmental Engineering and Microbiology Systems, 2023
Madhumita Barooah, Dibya Jyoti Hazarika
TALEN (transcription activator-like effector nuclease) is an excellent tool for the manipulation of genes through site-directed mutagenesis (Sun and Zhao, 2013). TALENs employ TAL proteins for DNA binding. These proteins are derived originally from a plant pathogenic bacterial genus Xanthomonas. The DNA-binding effectiveness of TAL proteins are so high that they can recognize even very short sequences for binding, i.e., 1–2 nucleotides. Furthermore, these nucleases consist of 34-amino-acid tandem repeats that ensure their binding to the target site (Juillerat et al., 2014; Jaiswal et al., 2019). Gene knock-in (HDR) and gene knockout (NHEJ) can be performed using TALENs. This system contains two protein domains, one of which recognizes and binds the very unique and specific target site and the second one is used for cleavage of a specific sequence at that unique site (Jaiswal et al., 2019). However, this technique is applied to manipulate the genomes of many eukaryotic targets such as mammalian cells, frog, zebrafish, mouse, rat, and chicken (Lei et al., 2012; Moore et al., 2012; Bloom et al., 2013; Qiu et al., 2013; Park et al., 2014; Chen et al., 2017).
Understanding the Technologies Involved in Gene Therapy
Published in Yashwant V. Pathak, Gene Delivery Systems, 2022
Manish P. Patel, Jayvadan K. Patel, Mukesh Patel, Govind Vyas
TAL works as a nuclease, an enzyme with cleaving efficiency. Further study was carried out on it its binding efficacy. Transcription activator–like effector nucleases (TALENs) are restriction enzymes that bind to DNA based on its specificity and can be tailored to cut sequences of DNA. They are made by combining TAL binding domains, which allows entry into a cell, and a DNA cleavage domain, which is helpful in gene editing. These can be tailored to bind to any targeted area in the genome to cut any desired specific location (Cermak et al. 2011). In initial studies of transcription activator-like effectors (TALEs) from the pathogenic bacterium Xanthomonas, it was found that they can be readily modified to bind virtually any DNA sequence (Boch et al. 2009; Christian et al. 2010).
Genomic Approaches for Understanding Abiotic Stress Tolerance in Plants
Published in Hasanuzzaman Mirza, Nahar Kamrun, Fujita Masayuki, Oku Hirosuke, Tofazzal M. Islam, Approaches for Enhancing Abiotic Stress Tolerance in Plants, 2019
Richa Rai, Amit Kumar Rai, Madhoolika Agrawal
TALENs are one of the substitutes to ZFNs and are identified as restriction enzymes that could be manipulated for cutting specific DNA sequences. Traditionally, TALENs are considered as long segments of transcription activator-like effector (TALE) sequences that occur naturally and join the Fokl domain with the carboxylic-terminal end of manipulated TALE repeat arrays (Christian et al., 2010). TALENs contain a customizable DNA-binding domain which is fused with non-specific Fokl nuclease domain (Christian et al., 2010). As compared to ZFNs, TALENs are involved in the interaction of individual nucleotide repeats of the target site and amino acid sequences of TAL effector proteins. They can generate overhangs by employing Fokl nuclease domain to persuade site-specific DNA cleavage. It has been widely used to generate non-homologous mutations with higher efficiencies in diverse organisms (Joung and Sander, 2012) TALE proteins consist of a central domain responsible for DNA binding, nuclear localization signal, and a domain that activates transcription of the target gene. DNA-binding domain in TALE monomers consists of a central repeat domain (CRD) that confers DNA binding and host specificity. The CRD consists of tandem repeats of 34 amino acid residues and each 34-amino acid long repeat in CRD binds to one nucleotide in the target nucleotide sequence.
Gene doping: Present and future
Published in European Journal of Sport Science, 2020
Rebeca Araujo Cantelmo, Alessandra Pereira da Silva, Celso Teixeira Mendes-Junior, Daniel Junqueira Dorta
The ZFNs, TALENs, and CRISPR/ Cas9 techniques are mainly employed to edit genes in somatic and germline cells of different species. In particular, CRISPR/ Cas9 can efficiently target genes in mammalian embryos like mice, rats, pigs, cattle, and monkeys (Mashimo, 2014; Ormond et al., 2017). Furthermore, these technologies are being used to edit human somatic cells with a view to therapies that can be applied in healthcare, especially in the field of cancer immunotherapy through modified T cells (Fears & Meulen, 2017; Fellmann, Gowen, Lin, Doudna, & Corn, 2017).
Combating soil salinity with combining saline agriculture and phytomanagement with salt-accumulating plants
Published in Critical Reviews in Environmental Science and Technology, 2020
Kashif Hayat, Jochen Bundschuh, Farooq Jan, Saiqa Menhas, Sikandar Hayat, Fazal Haq, Mashab Ali Shah, Hassan Javed Chaudhary, Abid Ullah, Dan Zhang, Yuanfei Zhou, Pei Zhou
During the last decade, a combination of the ‘3 NTs’ i.e. (a) nanotechnology, (b) biotechnology, (c) information technology and cognitive science are considered as the savor of mankind from the upcoming challenges of eco-environment and food safety (Song et al., 2019). Interestingly, the introduction of some newer, effective and robust avenues of traditional plant breeding coupled with modern molecular techniques by the plant biologist including (i) next generation sequencing (NGS) technologies, (ii) SSR and especially SNPs generated through NGS, (iii) ‘saltol’ QTL i.e. a near isogenic line (NIL) introgression, (iv) mapping and the genome-wide association studies (GWAS), (v) transcriptomic analysis, (vi) modern genome editing technologies such as zinc finger nucleases, TALENs, CRISPR/Cas9/Cas13, (vii) EcoTILLING (Eco-Targeting-Induced Local Lesions IN Genomes), (viii) microarray based transcriptional profiling of differential gene expression or combination of genetic mapping and expression profiling (through association genetics), and (ix) advanced backcross QTL analysis approach paved the way to develop precisely engineered crops for salinity tolerance (Chantre Nongpiur et al., 2016; Fita et al., 2015; Turan et al., 2012). However, there are inadequacy of such examples regarding good characterization of the germplasm when meet with a breeding-oriented use of modern molecular tools for salinity tolerance (Fita et al., 2015). Still, several researchers showed some promising results in inducing salinity tolerance and understanding molecular mechanisms of salt tolerance in some major crops. Furthermore, above findings provided a solid ground that future research should focus on the synergy of omics approaches along with breeding-oriented modern molecular tools to develop such plant that could withstand abiotic stresses especially salinity stress. This would significantly contribute to the stability of crop production, eco-environment and food safety issue in under-develop countries as well as in semi-arid tropical regions (Athar & Ashraf, 2009).