scholarly journals Labelling of DNA and RNA in the cellular environment by means of bioorthogonal cycloaddition chemistry

2020 ◽  
Vol 1 (3) ◽  
pp. 86-97 ◽  
Author(s):  
Dorothée Ganz ◽  
Dennis Harijan ◽  
Hans-Achim Wagenknecht
Keyword(s):  
Nucleic Acids ◽  
Biological Processes ◽  
Dna And Rna ◽  
Cellular Environment ◽  
Cellular Components

Labelling of nucleic acids as biologically important cellular components is a crucial prerequisite for the visualization and understanding of biological processes.

scholarly journals Nitrosamine-induced carcinogenesis. The alkylation of nucleic acids of the rat by N-methyl-N-nitrosourea, dimethylnitrosamine, dimethyl sulphate and methyl methanesulphonate

1968 ◽  
Vol 110 (1) ◽  
pp. 39-47 ◽  
Author(s):  
P. F. Swann ◽  
P. N. Magee
Keyword(s):  
Nucleic Acids ◽  
Dimethyl Sulphate ◽  
Specific Radioactivity ◽  
The Other ◽  
Striking Difference ◽  
Organ Distribution ◽  
Time Intervals ◽  
Dna And Rna ◽  
Cellular Components ◽  
The Brain

1. N[14C]-Methyl-N-nitrosourea, [14C]dimethylnitrosamine, [14C]dimethyl sulphate and [14C]methyl methanesulphonate were injected into rats, and nucleic acids were isolated from several organs after various time-intervals. Radioactivity was detected in DNA and RNA, partly in major base components and partly as the methylated base, 7-methylguanine. 2. No 7-methylguanine was detected in liver DNA from normal untreated rats. 3. The specific radioactivity of 7-methylguanine isolated from DNA prepared from rats treated with [14C]dimethylnitrosamine was virtually the same as that of the dimethylnitrosamine injected. 4. The degree of methylation of RNA and DNA produced in various organs by each compound was determined, and expressed as a percentage of guanine residues converted into 7-methylguanine. With dimethylnitrosamine both nucleic acids were considerably more highly methylated in the liver (RNA, about 1% of guanine residues methylated; DNA, about 0·6% of guanine residues methylated) than in the other organs. Kidney nucleic acids were methylated to about one-tenth of the extent of those in the liver, lung showed slightly lower values and the other organs only very low values. N-Methyl-N-nitrosourea methylated nucleic acids to about the same extent in all the organs studied, the amount being about the same as that in the kidney after treatment with dimethylnitrosamine. In each case the RNA was more highly methylated than the DNA. Methyl methanesulphonate methylated the nucleic acids in several organs to about the same extent as N-methyl-N-nitrosourea, but the DNA was more highly methylated than the RNA. Dimethyl sulphate, even in toxic doses, gave considerably less methylation than N-methyl-N-nitrosourea in all the organs studied, the greatest methylation being in the brain. 5. The rate of removal of 7-methylguanine from DNA of kidneys from rats treated with dimethylnitrosamine was compared with the rate after treatment of rats with methyl methanesulphonate. No striking difference was found. 6. The results are discussed in connexion with the organ distribution of tumours induced by the compounds under study and in relation to the possible importance of alkylation of cellular components for the induction of cancer.

scholarly journals Understanding the mechanical response of double-stranded DNA and RNA under constant stretching forces using all-atom molecular dynamics

2017 ◽  
Vol 114 (27) ◽  
pp. 7049-7054 ◽  
Author(s):  
Alberto Marin-Gonzalez ◽  
J. G. Vilhena ◽  
Ruben Perez ◽  
Fernando Moreno-Herrero
Keyword(s):  
Molecular Dynamics ◽  
Nucleic Acids ◽  
Elastic Constants ◽  
Base Pair ◽  
Mechanical Response ◽  
Atomic Level ◽  
Biological Processes ◽  
Open Structure ◽  
Dna And Rna ◽  
Double Stranded Dna

Multiple biological processes involve the stretching of nucleic acids (NAs). Stretching forces induce local changes in the molecule structure, inhibiting or promoting the binding of proteins, which ultimately affects their functionality. Understanding how a force induces changes in the structure of NAs at the atomic level is a challenge. Here, we use all-atom, microsecond-long molecular dynamics to simulate the structure of dsDNA and dsRNA subjected to stretching forces up to 20 pN. We determine all of the elastic constants of dsDNA and dsRNA and provide an explanation for three striking differences in the mechanical response of these two molecules: the threefold softer stretching constant obtained for dsRNA, the opposite twist-stretch coupling, and its nontrivial force dependence. The lower dsRNA stretching resistance is linked to its more open structure, whereas the opposite twist-stretch coupling of both molecules is due to the very different evolution of molecules’ interstrand distance with the stretching force. A reduction of this distance leads to overwinding in dsDNA. In contrast, dsRNA is not able to reduce its interstrand distance and can only elongate by unwinding. Interstrand distance is directly correlated with the slide base-pair parameter and its different behavior in dsDNA and dsRNA traced down to changes in the sugar pucker angle of these NAs.

scholarly journals Quadruplex Ligands in Cancer Therapy

Cancers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 3156
Author(s):  
Victoria Sanchez-Martin ◽  
Miguel Soriano ◽  
Jose Antonio Garcia-Salcedo
Keyword(s):  
Cancer Therapy ◽  
Nucleic Acids ◽  
Small Molecule ◽  
Tumor Suppressors ◽  
Cancer Biology ◽  
Genome Instability ◽  
Therapeutic Agents ◽  
Biological Processes ◽  
Dna And Rna ◽  
Small Molecule Ligands

Nucleic acids can adopt alternative secondary conformations including four-stranded structures known as quadruplexes. To date, quadruplexes have been demonstrated to exist both in human chromatin DNA and RNA. In particular, quadruplexes are found in guanine-rich sequences constituting G-quadruplexes, and in cytosine-rich sequences forming i-Motifs as a counterpart. Quadruplexes are associated with key biological processes ranging from transcription and translation of several oncogenes and tumor suppressors to telomeres maintenance and genome instability. In this context, quadruplexes have prompted investigations on their possible role in cancer biology and the evaluation of small-molecule ligands as potential therapeutic agents. This review aims to provide an updated close-up view of the literature on quadruplex ligands in cancer therapy, by grouping together ligands for DNA and RNA G-quadruplexes and DNA i-Motifs.

Abiotic Stress Tolerance in Soybean : Regulated by ncRNA

2016 ◽  
Vol 3 (1) ◽  
Author(s):  
YASIN JESHIMA KHAN ◽  
HUSNARA Tyagi ◽  
Anil kumar Singh ◽  
Santosh kumar. Magadum
Keyword(s):  
Abiotic Stresses ◽  
Target Genes ◽  
Abiotic Stress Tolerance ◽  
Crop Improvement ◽  
Vital Role ◽  
Grain Legume ◽  
Biological Processes ◽  
Small Interfering Rnas ◽  
Cellular Environment ◽  
Non Coding Rnas

Plants respond through a cascade of reactions resulting in varied cellular environment leading to alterations in the patterns of protein expression resulting in phonotypic changes. Single cell genomics and global proteomics came out to be powerful tools and efficient techniques in studying stress tolerant plants. Non-coding RNAs are a distinct class of regulatory RNAs in plants and animals that control a variety of biological processes. Small ncRNAs play a vital role in post transcriptional gene regulation by either translational repression or by inducing mRNA cleavage. The major classes of small RNAs include microRNAs (miRNAs) and small interfering RNAs (siRNAs), which differ in their biogenesis. miRNAs control the expression of cognate target genes by binding to complementary sequences, resulting in cleavage or translational inhibition of the target RNAs. siRNAs too have a similar structure, function, and biogenesis like miRNAs but are derived from long double-stranded RNAs and can often direct DNA methylation at target sequences.In this review, we focus on the involvement of ncRNAs in comabting abiotic stresses of soybean. This review emphasis on previously known miRNAs as they play important role in several abiotic stresses like drought, salinity, chilling and heat stress by their diverse roles in mediating biological processes like gene expression, chromatin formation, defense of genome against invading viruses. This review attempts to elucidate the various kinds of non-coding RNAs explored, their discovery, biogenesis, functions, and response for different type of abiotic stresses and future aspects for crop improvement in the context of soybean, a representative grain legume.

scholarly journals Graphene Oxide: A Smart (Starting) Material for Natural Methylxanthines Adsorption and Detection

Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4247 ◽  
Author(s):  
Rita Petrucci ◽  
Isabella Chiarotto ◽  
Leonardo Mattiello ◽  
Daniele Passeri ◽  
Marco Rossi ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Graphene Oxide ◽  
Nucleic Acids ◽  
Reduced Graphene Oxide ◽  
Electrochemical Sensors ◽  
Enzymatic Digestion ◽  
Biologically Active ◽  
Polar Solvents ◽  
Dna And Rna ◽  
Reduced Graphene

Natural methylxanthines, caffeine, theophylline and theobromine, are widespread biologically active alkaloids in human nutrition, found mainly in beverages (coffee, tea, cocoa, energy drinks, etc.). Their detection is thus of extreme importance, and many studies are devoted to this topic. During the last decade, graphene oxide (GO) and reduced graphene oxide (RGO) gained popularity as constituents of sensors (chemical, electrochemical and biosensors) for methylxanthines. The main advantages of GO and RGO with respect to graphene are the easiness and cheapness of synthesis, the notable higher solubility in polar solvents (water, among others), and the higher reactivity towards these targets (mainly due to – interactions); one of the main disadvantages is the lower electrical conductivity, especially when using them in electrochemical sensors. Nonetheless, their use in sensors is becoming more and more common, with the obtainment of very good results in terms of selectivity and sensitivity (up to 5.4 × 10−10 mol L−1 and 1.8 × 10−9 mol L−1 for caffeine and theophylline, respectively). Moreover, the ability of GO to protect DNA and RNA from enzymatic digestion renders it one of the best candidates for biosensors based on these nucleic acids. This is an up-to-date review of the use of GO and RGO in sensors.

scholarly journals Triazole-Modified Nucleic Acids for the Application in Bioorganic and Medicinal Chemistry

Biomedicines ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 628
Author(s):  
Dagmara Baraniak ◽  
Jerzy Boryski
Keyword(s):  
Nucleic Acids ◽  
State Of The Art ◽  
Modified Oligonucleotides ◽  
Synthetic Genes ◽  
Chemically Modified ◽  
Amide Linkage ◽  
Dna And Rna ◽  
Modified Dna ◽  
Modified Nucleic Acids ◽  
Non Coding Rnas

This review covers studies which exploit triazole-modified nucleic acids in the range of chemistry and biology to medicine. The 1,2,3-triazole unit, which is obtained via click chemistry approach, shows valuable and unique properties. For example, it does not occur in nature, constitutes an additional pharmacophore with attractive properties being resistant to hydrolysis and other reactions at physiological pH, exhibits biological activity (i.e., antibacterial, antitumor, and antiviral), and can be considered as a rigid mimetic of amide linkage. Herein, it is presented a whole area of useful artificial compounds, from the clickable monomers and dimers to modified oligonucleotides, in the field of nucleic acids sciences. Such modifications of internucleotide linkages are designed to increase the hybridization binding affinity toward native DNA or RNA, to enhance resistance to nucleases, and to improve ability to penetrate cell membranes. The insertion of an artificial backbone is used for understanding effects of chemically modified oligonucleotides, and their potential usefulness in therapeutic applications. We describe the state-of-the-art knowledge on their implications for synthetic genes and other large modified DNA and RNA constructs including non-coding RNAs.

Study of NSCLC cell migration promoted by NSCLC-Derived Extracellular Vesicle using atomic force microscopy

2021 ◽  
Author(s):  
Shuwei Wang ◽  
Jiajia Wang ◽  
Tuoyu Ju ◽  
Kaige Qu ◽  
Fan Yang ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Cell Migration ◽  
Cancer Cells ◽  
Extracellular Vesicles ◽  
Extracellular Vesicle ◽  
Cancer Microenvironment ◽  
Biological Processes ◽  
Force Microscopy ◽  
Atomic Force ◽  
Cellular Components

Extracellular Vesicles (EVs) secreted by cancer cells have a key role in the cancer microenvironment and progression. Previous studies have mainly focused on molecular functions, cellular components and biological processes...

scholarly journals Targeting the Ubiquitin Signaling Cascade in Tumor Microenvironment for Cancer Therapy

2021 ◽  
Vol 22 (2) ◽  
pp. 791
Author(s):  
Qi Liu ◽  
Bayonle Aminu ◽  
Olivia Roscow ◽  
Wei Zhang
Keyword(s):  
Tumor Microenvironment ◽  
Cancer Therapy ◽  
Therapeutic Agents ◽  
Biological Processes ◽  
Post Translational Modification ◽  
E3 Ligases ◽  
Tumor Microenvironments ◽  
Cellular Immune ◽  
Ubiquitin Conjugating Enzymes ◽  
Cellular Components

Tumor microenvironments are composed of a myriad of elements, both cellular (immune cells, cancer-associated fibroblasts, mesenchymal stem cells, etc.) and non-cellular (extracellular matrix, cytokines, growth factors, etc.), which collectively provide a permissive environment enabling tumor progression. In this review, we focused on the regulation of tumor microenvironment through ubiquitination. Ubiquitination is a reversible protein post-translational modification that regulates various key biological processes, whereby ubiquitin is attached to substrates through a catalytic cascade coordinated by multiple enzymes, including E1 ubiquitin-activating enzymes, E2 ubiquitin-conjugating enzymes and E3 ubiquitin ligases. In contrast, ubiquitin can be removed by deubiquitinases in the process of deubiquitination. Here, we discuss the roles of E3 ligases and deubiquitinases as modulators of both cellular and non-cellular components in tumor microenvironment, providing potential therapeutic targets for cancer therapy. Finally, we introduced several emerging technologies that can be utilized to develop effective therapeutic agents for targeting tumor microenvironment.

The integrative biology of pigment organelles, a quantum chemical approach

2021 ◽  
Author(s):  
Florent Figon ◽  
Jérôme Casas
Keyword(s):  
Quantum Chemistry ◽  
Main Property ◽  
Computational Method ◽  
Phenotypic Trait ◽  
Visual Effects ◽  
Cellular Environment ◽  
Integrative Studies ◽  
Quantum Chemical Approach ◽  
Cellular Components ◽  
Physical And Chemical

Abstract Coloration is a complex phenotypic trait involving both physical and chemical processes at a multiscale level, from molecules to tissues. Pigments, whose main property is to absorb specific wavelengths of visible light, are usually deposited in specialized organelles or complex matrices comprising proteins, metals, ions and redox compounds, among others. By modulating electronic properties and stability, interactions between pigments and these molecular actors can lead to color tuning. Furthermore, pigments are not only important for visual effects but also provide other critical functions, such as detoxification and antiradical activity. Hence, integrative studies of pigment organelles are required to understand how pigments interact with their cellular environment. In this review, we show how quantum chemistry, a computational method that models the molecular and optical properties of pigments, has provided key insights into the mechanisms by which pigment properties, from color to reactivity, are modulated by their organellar environment. These results allow to rationalize and to predict the way pigments behave in supramolecular complexes, up to the complete modelling of pigment organelles. We also discuss the main limitations of quantum chemistry, emphasizing the need for carrying experimental work with identical vigor. We finally suggest that taking into account the ecology of pigments (i.e. how they interact with these various other cellular components and at higher organizational levels) will lead to a greater understanding of how and why animals are vividly and variably colored, two fundamental questions in organismal biology.

scholarly journals Silencing Antibiotic Resistance with Antisense Oligonucleotides

Biomedicines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 416
Author(s):  
Saumya Jani ◽  
Maria Soledad Ramirez ◽  
Marcelo E. Tolmasky
Keyword(s):  
Antibiotic Resistance ◽  
Nucleic Acids ◽  
Antisense Oligonucleotides ◽  
Bacterial Infections ◽  
Genetic Disorders ◽  
Antibiotic Resistance Genes ◽  
Short Review ◽  
Rnase H ◽  
Biological Processes ◽  
Locked Nucleic Acids

Antisense technologies consist of the utilization of oligonucleotides or oligonucleotide analogs to interfere with undesirable biological processes, commonly through inhibition of expression of selected genes. This field holds a lot of promise for the treatment of a very diverse group of diseases including viral and bacterial infections, genetic disorders, and cancer. To date, drugs approved for utilization in clinics or in clinical trials target diseases other than bacterial infections. Although several groups and companies are working on different strategies, the application of antisense technologies to prokaryotes still lags with respect to those that target other human diseases. In those cases where the focus is on bacterial pathogens, a subset of the research is dedicated to produce antisense compounds that silence or reduce expression of antibiotic resistance genes. Therefore, these compounds will be adjuvants administered with the antibiotic to which they reduce resistance levels. A varied group of oligonucleotide analogs like phosphorothioate or phosphorodiamidate morpholino residues, as well as peptide nucleic acids, locked nucleic acids and bridge nucleic acids, the latter two in gapmer configuration, have been utilized to reduce resistance levels. The major mechanisms of inhibition include eliciting cleavage of the target mRNA by the host’s RNase H or RNase P, and steric hindrance. The different approaches targeting resistance to β-lactams include carbapenems, aminoglycosides, chloramphenicol, macrolides, and fluoroquinolones. The purpose of this short review is to summarize the attempts to develop antisense compounds that inhibit expression of resistance to antibiotics.

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