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Genetics and exercise: an introduction
Published in Adam P. Sharples, James P. Morton, Henning Wackerhage, Molecular Exercise Physiology, 2022
Claude Bouchard, Henning Wackerhage
Until about the early 1950s, there was still a debate whether the genetic information was contained in the strings of nucleic acids or in the diversity of proteins. Then in 1944, Oswald T. Avery demonstrated with viruses that nucleic acids were the carriers of genetic information. However, it was still unknown how the genetic information was encoded in the DNA of an organism. In 1953, Francis Crick and James Watson resolved the issue in a 1-page paper in Nature. Based on X-ray of the DNA structure by Rosalind Franklin and Maurice Wilkins, and other data on nucleic acid structure, they proposed the now famous double helix structure of DNA (14). They concluded, correctly, that DNA consists of two strands that are coiled around each other to form a double helix, with the informative base on the inside (Figure 3.4). In each strand, the various bases (i.e. A, T, C and G) are connected by a strong phosphate bond. The two strands are also bound together because A binds to T and G binds to C on the other strand via two or three hydrogen bonds which are, however, weak when compared to the phosphate bonds.
Cellular and Immunobiology
Published in Karl H. Pang, Nadir I. Osman, James W.F. Catto, Christopher R. Chapple, Basic Urological Sciences, 2021
Masood Moghul, Sarah McClelland, Prabhakar Rajan
Ultraviolet radiation damages DNA by causing cyclobutane pyrimidine dimers and 6‒4 photoproducts lesions on the DNA.Alters DNA structure, impeding correct replication and transcription.Lesions are excised with the recognition, removal, and replacement of the damaged DNA—'nucleotide excision repair'.Base excision repair occurs with localised damage (from free radicals).
Introduction to Genomics
Published in Altuna Akalin, Computational Genomics with R, 2020
Mutations are classified by how many bases they affect, their effect on DNA structure and gene function. By their effect on DNA structure the mutations are classified as follows: Base substitution: A base is changed with another.Deletion: One or more bases is deleted.Insertion: New base or bases inserted into the genome.Microsatellite mutation: Small insertions or deletions of small tandemly repeating DNA segments.Inversion: A DNA fragment changes its orientation 180 degrees.Translocation: A DNA fragment moves to another location in the genome.
Genotoxic hazard assessment of cerium oxide and magnesium oxide nanoparticles in Drosophila
Published in Nanotoxicology, 2022
Burçin Yalçın, Merve Güneş, Ayşen Yağmur Kurşun, Nuray Kaya, Ricard Marcos, Bülent Kaya
Metal oxide NPs are a particular class of NPs constituting about 37% of the total nanoscale products (Vance et al. 2015). They are widely used, and it is estimated that these NPs can easily spread into the environment (Solano et al. 2021). Metal NPs can cross biological protective barriers due to their small size (<100 nm), passing through the cell membrane and, potentially, reaching the nucleus (Demir 2021). In this way, they can give rise to oxidative stress, inflammatory reactions, and DNA damage, among other harmful effects (Solano et al. 2021). Therefore, genotoxic evaluation of these NPs is necessary to know more about the risk of these nanoparticles to the environment and living organisms. It must be pointed out that, due to the relevant role of DNA in cell functionality, alteration in DNA structure/function can severely compromise human health (Carbone et al. 2020). The mechanisms underlying the toxicity of metal NPs can be categorized as reactive oxygen species (ROS)-mediated and ROS-unmediated toxicity (Wang et al. 2017). In our previous studies, the protective effect of antioxidants against the genotoxic effect of metal nanoparticles was investigated and it was found that the mechanism of several metal NPs genotoxicity is ROS-mediated (Gunes et al. 2018; Ertuğrul et al. 2020). The induction of oxidative damage on DNA structure triggers an immediate response by activating different DNA repair pathways. Thus, detecting changes in the expression levels of the involved genes are an indirect way to demonstrate the existence of oxidative DNA injury (Carriere et al. 2017).
DNA binding, BSA interaction and in-vitro antimicrobial studies of Cu(II), Co(III), Ni(II) and VO(IV) complexes with a new Schiff base
Published in Egyptian Journal of Basic and Applied Sciences, 2020
Disha Sharma, Hosakere D. Revanasiddappa, Basavegowda Jayalakshmi
UV-Visible technique is a most useful method to determine the interaction between negatively charged DNA and positively charged metal complexes. The different binding mode to DNA gives an insight in understanding their biochemical mode of action of metal complexes. To account for the binding ability and nature of binding to CT-DNA, UV-visible and ethidium bromide displacement assay were carried out. In this study, the interaction study of C1-C8 with and without CT-DNA in Tris-buffer was performed. The spectra are depicted in Figure 11. The deformation of DNA structure was obtained from the results of hypochromism, whereas the destruction of double helix structure from hyperchromism. The Equation (1) can be utilized to calculate the binding constants;
siRNA: an alternative treatment for diabetes and associated conditions
Published in Journal of Drug Targeting, 2019
Ribonucleic acid (RNA) consists of a single stranded linear structure has crucial role in regulation and expression of specific gene and also stores genetic information. RNA structure consists of four ribonucleotide base pairs namely, adenine, guanine, cytosine and uracil in which purines like adenine and guanine binds which complementary pyridines like uracil and cytosine, respectively [8]. RNA is classified into three types, messenger RNA (mRNA), ribosomal RNA (rRNA) and transfer RNA (tRNA) which are involved in protein synthesis in human body, whereas RNA like short interfering RNA (siRNA) and micro RNA (miRNA) are mainly involved in regulation and expression of genes. Both siRNA and miRNA are similar in their structure as well as in their function of silencing and regulation of gene expression by binding with complementary messenger RNA (Figure 2). In contrast, they differ in their mechanism of action and also siRNA targets only one specific mRNA while miRNA has multiple complementary targets [9].