DNA methylation
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Badania okresowe, Adenine, Arabidopsis thaliana, Bacteriophage, Bacterium, Base analog, Biochemistry, Cancer, Carcinogenesis, Cell (biology), ChIP-on-chip, Chromatin immunoprecipitation, CpG island, CpG islands, CpG site, Cytosine, DNA, DNA methyltransferase, DNA microarrays, DNA sequencing, Decitabine, Developmental Biology, Digital object identifier, Downregulation, Enzyme induction and inhibition, Epigenetics, Fungi, Gene (journal), Gene expression, Gene silencing, Genes, Genome, Genomic imprinting, HELP assay, Histone acetylation and deacetylation, Histone deacetylase, Immunoprecipitation, Imprinting (genetics), Lac operon, MRNA, Medical Subject Headings, Methyl group, Methylase, Methylated DNA immunoprecipitation, Methylation Specific PCR (MSP), MiRNA, Nature (journal), Neurospora crassa, Operon, PCR, PNAS, Polymorphism (biology), Post-transcriptional modification, Posttranslational modification, PubMed Identifier, RNA interference, RNA viruses, RdDM, Regulation of gene expression, Regulatory regions, Reprogramming, Restriction enzyme, Restriction fragment length polymorphism, Restriction landmark genomic scanning, Restriction modification system, Rett syndrome, Saccharomyces, Schizosaccharomyces, SiRNA, Somatic, Stem cell, TRDMT1, Transcriptional silencing, Translation, Transposon, Transposons, Trp operon, Upregulation, X-chromosome inactivation, DNA methylation involves the addition of a methyl group to the 5 position of cytosine (one of the four bases of DNA), which occurs in the context of CpG (cytosine followed by guanine) dinucleotides. This modification can be inherited through cell division. DNA methylation is typically removed during zygote formation and reestablished through successive cell divisions during development. DNA methylation is a crucial part of normal organismal development and cellular differentiation in higher organisms. DNA methylation stably alters the gene expression pattern in cells such that cells can "remember where they have been"; in other words, cells programmed to be pancreatic islets during embryonic development remain pancreatic islets through out the life of the organism without continuing signals telling them that they need to remain islets. In addition, DNA methylation suppresses the expression of viral genes and other deleterious elements which have been incorporated into the genome of the host over time. DNA methylation also forms the basis of chromatin structure, which enables cells to form the myriad characteristics necessary for multicellular life from a single immutable sequence of DNA. DNA methylation also plays a crucial role in the development of nearly all types of cancer.[1]
A bacteriophage (from 'bacteria' and Greek φᾰγεῖν phagein "to eat") is any one of a number of viruses that infect bacteria. Bacteriophages are among the most common organisms on Earth.[1] The term is commonly used in its shortened form, phage.
Cancer /ˈkænsə(r)/ (
listen) (medical term: malignant neoplasm) is a class of diseases in which a group of cells display uncontrolled growth (division beyond the normal limits), invasion (intrusion on and destruction of adjacent tissues), and sometimes metastasis (spread to other locations in the body via lymph or blood). These three malignant properties of cancers differentiate them from benign tumors, which are self-limited, and do not invade or metastasize. Most cancers form a tumor but some, like leukemia, do not. The branch of medicine concerned with the study, diagnosis, treatment, and prevention of cancer is oncology.
The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life.[1] Some organisms, such as most bacteria, are unicellular (consist of a single cell). Other organisms, such as humans, are multicellular. (Humans have an estimated 100 trillion or 1014 cells; a typical cell size is 10 µm; a typical cell mass is 1 nanogram.) The largest known cell is an unfertilized ostrich egg cell.[2]ChIP-on-chip (also known as ChIP-chip) is a technique that combines chromatin immunoprecipitation ("ChIP") with microarray technology ("chip"). Like regular ChIP, ChIP-on-chip is used to investigate interactions between proteins and DNA in vivo. Specifically, it allows the identification of the cistrome, sum of binding sites, for DNA-binding proteins on a genome-wide basis[1]. Whole-genome analysis can be performed to determine the locations of binding sites for almost any protein of interest[1]. As the name of the technique suggests, such proteins are generally those operating in the context of chromatin. The most prominent representatives of this class are transcription factors, replication-related proteins, like ORC, histones, their variants, and histone modifications. The goal of ChIP-on-chip is to localize protein binding sites which may help in identifying functional elements in the genome. For example, in the case of a transcription factor as a protein of interest, one can determine its transcription factor binding sites throughout the genome. Other proteins allow the identification of promoter regions, enhancers, repressors and silencing elements, insulators, boundary elements, and sequences that control DNA replication[2]. If histones are subject of interest, it is believed that the distribution of modifications and their localizations may offer new insights into the mechanisms of regulation. One of the long-term goals ChIP-on-chip was designed for is to establish a catalogue of (selected) organisms that lists all protein-DNA interactions under various physiological conditions. This knowledge would ultimately help in the understanding of the machinery behind gene regulation, cell proliferation, and disease progression. Hence, ChIP-on-chip offers not only huge potential to complement our knowledge about the orchestration of the genome on the nucleotide level, but also on higher levels of information and regulation as it is propagated by research on epigenetics.
Immunoprecipitation (IP) is the technique of precipitating a protein antigen out of solution using an antibody that specifically binds to that particular protein. This process can be used to isolate and concentrate a particular protein from a sample containing many thousands of different proteins. Immunoprecipitation requires that the antibody be coupled to a solid substrate at some point in the procedure.CpG islands are genomic regions that contain a high frequency of CpG sites but to date objective definitions for CpG islands are limited. In mammalian genomes, CpG islands are typically 300-3,000 base pairs in length. They are in and near approximately 40% of promoters of mammalian genes[1]. About 70% of human promoters have a high CpG content. Given the GC frequency however, the number of CpG dinucleotides is much lower than expected.[2] The "p" in CpG notation refers to the phosphodiester bond between the cytosine and the guanine.CpG islands are genomic regions that contain a high frequency of CpG sites but to date objective definitions for CpG islands are limited. In mammalian genomes, CpG islands are typically 300-3,000 base pairs in length. They are in and near approximately 40% of promoters of mammalian genes[1]. About 70% of human promoters have a high CpG content. Given the GC frequency however, the number of CpG dinucleotides is much lower than expected.[2] The "p" in CpG notation refers to the phosphodiester bond between the cytosine and the guanine.
Cancer /ˈkænsə(r)/ (
listen) (medical term: malignant neoplasm) is a class of diseases in which a group of cells display uncontrolled growth (division beyond the normal limits), invasion (intrusion on and destruction of adjacent tissues), and sometimes metastasis (spread to other locations in the body via lymph or blood). These three malignant properties of cancers differentiate them from benign tumors, which are self-limited, and do not invade or metastasize. Most cancers form a tumor but some, like leukemia, do not. The branch of medicine concerned with the study, diagnosis, treatment, and prevention of cancer is oncology.The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life.[1] Some organisms, such as most bacteria, are unicellular (consist of a single cell). Other organisms, such as humans, are multicellular. (Humans have an estimated 100 trillion or 1014 cells; a typical cell size is 10 µm; a typical cell mass is 1 nanogram.) The largest known cell is an unfertilized ostrich egg cell.[2]ChIP-on-chip (also known as ChIP-chip) is a technique that combines chromatin immunoprecipitation ("ChIP") with microarray technology ("chip"). Like regular ChIP, ChIP-on-chip is used to investigate interactions between proteins and DNA in vivo. Specifically, it allows the identification of the cistrome, sum of binding sites, for DNA-binding proteins on a genome-wide basis[1]. Whole-genome analysis can be performed to determine the locations of binding sites for almost any protein of interest[1]. As the name of the technique suggests, such proteins are generally those operating in the context of chromatin. The most prominent representatives of this class are transcription factors, replication-related proteins, like ORC, histones, their variants, and histone modifications. The goal of ChIP-on-chip is to localize protein binding sites which may help in identifying functional elements in the genome. For example, in the case of a transcription factor as a protein of interest, one can determine its transcription factor binding sites throughout the genome. Other proteins allow the identification of promoter regions, enhancers, repressors and silencing elements, insulators, boundary elements, and sequences that control DNA replication[2]. If histones are subject of interest, it is believed that the distribution of modifications and their localizations may offer new insights into the mechanisms of regulation. One of the long-term goals ChIP-on-chip was designed for is to establish a catalogue of (selected) organisms that lists all protein-DNA interactions under various physiological conditions. This knowledge would ultimately help in the understanding of the machinery behind gene regulation, cell proliferation, and disease progression. Hence, ChIP-on-chip offers not only huge potential to complement our knowledge about the orchestration of the genome on the nucleotide level, but also on higher levels of information and regulation as it is propagated by research on epigenetics.
Immunoprecipitation (IP) is the technique of precipitating a protein antigen out of solution using an antibody that specifically binds to that particular protein. This process can be used to isolate and concentrate a particular protein from a sample containing many thousands of different proteins. Immunoprecipitation requires that the antibody be coupled to a solid substrate at some point in the procedure.CpG islands are genomic regions that contain a high frequency of CpG sites but to date objective definitions for CpG islands are limited. In mammalian genomes, CpG islands are typically 300-3,000 base pairs in length. They are in and near approximately 40% of promoters of mammalian genes[1]. About 70% of human promoters have a high CpG content. Given the GC frequency however, the number of CpG dinucleotides is much lower than expected.[2] The "p" in CpG notation refers to the phosphodiester bond between the cytosine and the guanine.CpG islands are genomic regions that contain a high frequency of CpG sites but to date objective definitions for CpG islands are limited. In mammalian genomes, CpG islands are typically 300-3,000 base pairs in length. They are in and near approximately 40% of promoters of mammalian genes[1]. About 70% of human promoters have a high CpG content. Given the GC frequency however, the number of CpG dinucleotides is much lower than expected.[2] The "p" in CpG notation refers to the phosphodiester bond between the cytosine and the guanine.