Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: metylacja DNA

Sortuj według:

Ogranicz wyniki do:

Epigenetics is promising direction in modern science

Fartushok Tetiana, Kovalyshyn Orysia, Fedevych Yuri, Tanchyn Igor, Zhykovskiy Volodymyr

Chemistry-Didactics-Ecology-Metrology

2021

R. 26, NR 1-2

123--135

Epigenetics studies the inherited changes in a phenotype or in expression of genes caused by other mechanisms, without changing the nucleotide sequence of DNA. The most distinguished epigenetic tools are: modifications of histones, enzymatic DNA methylation, and gene silencing mediated by small RNAs (miRNA, siRNA). The resulting m5C residues in DNA substantially affect the cooperation of proteins with DNA. It is organized by hormones and aging-related alterations, one of the mechanisms controlling sex and cellular differentiation. DNA methylation regulates all genetic functions: repair, recombination, DNA replication, as well as transcription. Distortions in DNA methylation and other epigenetic signals lead to diabetes, premature aging, mental dysfunctions, and cancer.

In silico analysis of methylation of the selected genes using computer programs based on various analytical techniques

Gryzińska M., Jakubczak A., Stryjecki R., Jeżewska-Witkowska G.

Biocybernetics and Biomedical Engineering

2015

Vol. 35, no. 3

169--175

Selected genes were analyzed in silico in three species: red fox (Vulpes vulpes), raccoon dog (Nyctereutes procyonoides), and dog (Canis lupus familiaris). This type of analysis exemplifies current and potential research on gene expression. Four nucleotide sequences, of the genes IGF1, MYO15A, PAX3 and MC1R, were obtained from the NCBI online database. The analyses focused on the presence of CpG islands and two analytical techniques, BSP and MSP. The results from three computer programs, CpG Island Searcher®, BiSearch® and MethPrimer®, were discussed in detail. The applications were compared in terms of their functionality and usefulness.

Wykorzystanie spektrometrii mas do analizy modyfikacji nukleotydów i adduktów DNA

Hanus J., Jelonek K., Pietrowska M.

Wiadomości Chemiczne

2011

[Z] 65, 3-4

191-205

Chemically modified nucleotides, which are not normally present in genetic material, are called DN A adducts. This type of DN A modifications (damage) is directly related to processes of mutagenesis and carcinogenesis. Elevated levels of DN A adducts present in genetic material reflect exposure of humans to carcinogenic factors and are markers of increased risk of cancer [1]. For this reason different methods useful for quantitative and qualitative analyses of DN A adducts are used in the field of cancer prevention and research (Tab. 1). Enzymatically-catalyzed methylation of cytosine, observed mostly in so called CpG islands, is a frequent endogenous modification of genetic material. Such a DN A methylation is a key factor involved in regulation of gene expression, and methylation status of oncogenes and tumor supressor genes is an important biomarker of carcinogenesis. As such, analytical methods for assessment of DN A methylation are of great importance for molecular diagnostics of cancer. During the last decade significant progress has been made in methods available for quantitative, qualitative and structural analyses of biological molecules. Among intensively developed tools for bioanalyses are methods of mass spectrometry. Spectrometers that are based on two methods of ionization, namely electrospray ionization (ESI ) [30] and matrix-assisted laser desorption-ionization (MALDI ) [48], are particularly suitable for analyses of biological macromolecules: proteins and nucleic acids. Currently available mass spectrometers, together with microscale methods for sample preparation and separation, significantly increased sensitivity and accessible mass range of analyses. New generation of “user-friendly” instruments is developed to bring the techniques directly into the workplaces of biological and clinical investigators. This review demonstrates representative examples of mass spectrometry techniques used for qualitative analyses of nucleotide modifications and adducts present in genetic material of humans. In this field several methods base on spectrometers with electrospray ionization. Generated ions are separated according to their mass-to-charge ratio in an analyzer by electric fields; among different ion analyzers frequently used in this methods are single or triple quadrupole and ion traps (Fig. 1). Among other methods available for assessment of DN A adducts is so called Accelerator Mass Spectrometry (Fig. 2) [41]. The most frequently applied method for the assessment of DN A methylation is based on methylation-specific PCR reaction. Products of such PCR reactions are analyzed using MALDI mass spectrometry [54] (Fig. 3). In summary, new powerful methods of mass spectrometry that made available qualitative analyses of damage and modifications of human genetic material found their important place in modern biological and medical laboratories.