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KCNQ1OT1
KCNQ1 overlapping transcript 1, also known as KCNQ1OT1, is a long non-coding RNA gene found in the KCNQ1 Locus (genetics), locus. This locus consists of 8–10 protein-coding genes, Genomic imprinting, specifically expressed from the maternal allele (including the KCNQ1 gene), and the paternally expressed non-coding RNA gene KCNQ1OT1. KCNQ1OT1 and KCNQ1 are imprinted genes and are part of an imprinting control region (ICR). Mitsuya identified that KCNQ1OT1 is an antisense transcript of KCNQ1. KCNQ1OT1 is a paternally expressed allele and KCNQ1 is a maternally expressed allele. KCNQ1OT1 is a nuclear, 91 kb transcript, found in close proximity to the nucleolus in certain cell types. It interacts with chromatin, the histone methyltransferase G9a (responsible for the mono- and dimethylation of histone 3 lysine 9, H3K9), and the Polycomb Repressive Complex 2, PRC2, (responsible for the trimethylation of H3K27). It plays an important role in the transcriptional silencing of the KCNQ1 loc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Long Non-coding RNA
Long non-coding RNAs (long ncRNAs, lncRNA) are a type of RNA, generally defined as transcripts more than 200 nucleotides that are not translated into protein. This arbitrary limit distinguishes long ncRNAs from small non-coding RNAs, such as microRNAs (miRNAs), small interfering RNAs (siRNAs), Piwi-interacting RNAs (piRNAs), small nucleolar RNAs (snoRNAs), and other short RNAs. Long intervening/intergenic noncoding RNAs (lincRNAs) are sequences of lncRNA which do not overlap protein-coding genes. Long non-coding RNAs include intergenic lincRNAs, intronic ncRNAs, and sense and antisense lncRNAs, each type showing different genomic positions in relation to genes and exons. Abundance In 2007 a study found only one-fifth of transcription across the human genome is associated with protein-coding genes, indicating at least four times more long non-coding than coding RNA sequences. Large-scale complementary DNA (cDNA) sequencing projects such as FANTOM reveal the complexity of this t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Long Noncoding RNA
Long non-coding RNAs (long ncRNAs, lncRNA) are a type of RNA, generally defined as transcripts more than 200 nucleotides that are not translated into protein. This arbitrary limit distinguishes long ncRNAs from small non-coding RNAs, such as microRNAs (miRNAs), small interfering RNAs (siRNAs), Piwi-interacting RNAs (piRNAs), small nucleolar RNAs (snoRNAs), and other short RNAs. Long intervening/intergenic noncoding RNAs (lincRNAs) are sequences of lncRNA which do not overlap protein-coding genes. Long non-coding RNAs include intergenic lincRNAs, intronic ncRNAs, and sense and antisense lncRNAs, each type showing different genomic positions in relation to genes and exons. Abundance In 2007 a study found only one-fifth of transcription across the human genome is associated with protein-coding genes, indicating at least four times more long non-coding than coding RNA sequences. Large-scale complementary DNA (cDNA) sequencing projects such as FANTOM reveal the complexity of this tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transcriptional Silencing
Gene silencing is the regulation of gene expression in a cell to prevent the expression of a certain gene. Gene silencing can occur during either transcription or translation and is often used in research. In particular, methods used to silence genes are being increasingly used to produce therapeutics to combat cancer and other diseases, such as infectious diseases and neurodegenerative disorders. Gene silencing is often considered the same as gene knockdown. When genes are silenced, their expression is reduced. In contrast, when genes are knocked out, they are completely erased from the organism's genome and, thus, have no expression. Gene silencing is considered a gene knockdown mechanism since the methods used to silence genes, such as RNAi, CRISPR, or siRNA, generally reduce the expression of a gene by at least 70% but do not eliminate it. Methods using gene silencing are often considered better than gene knockouts since they allow researchers to study essential genes that are r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wilms' Tumor
Wilms' tumor or Wilms tumor, also known as nephroblastoma, is a cancer of the kidneys that typically occurs in children, rarely in adults.; and occurs most commonly as a renal tumor in child patients. It is named after Max Wilms, the German surgeon (1867–1918) who first described it. Approximately 650 cases are diagnosed in the U.S. annually. The majority of cases occur in children with no associated genetic syndromes; however, a minority of children with Wilms' tumor have a congenital abnormality. It is highly responsive to treatment, with about 90 percent of children being cured. Signs and symptoms Typical signs and symptoms of Wilms' tumor include the following: * a painless, palpable abdominal mass * loss of appetite * abdominal pain * fever * nausea and vomiting * blood in the urine (in about 20% of cases) * high blood pressure in some cases (especially if synchronous or metachronous bilateral kidney involvement) * Rarely as varicoceleErginel B, Vural S, Akın M, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNMT1
DNA (cytosine-5)-methyltransferase 1 is an enzyme that catalyzes the transfer of methyl groups to specific CpG structures in DNA, a process called DNA methylation. In humans, it is encoded by the ''DNMT1'' gene. DNMT1 forms part of the family of DNA methyltransferase enzymes, which consists primarily of DNMT1, DNMT3A, and DNMT3B. Function This enzyme is responsible for maintaining DNA methylation, which ensures the fidelity of this epigenetic patterns across cell divisions. In line with this role, it has a strong preference towards methylating CpGs on hemimethylated DNA. However, Dnmt1 can catalyze de novo DNA methylation in specific genomic contexts, including transposable elements and paternal imprint control regions. Aberrant methylation patterns are associated with certain human tumors and developmental abnormalities. See also * DNA methyltransferase Interactions DNMT1 has been shown to interact with UHRF1,: * DMAP1, * DNMT3A * DNMT3B, * HDAC2, * PCNA, * RB1. and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Somatic (biology)
The term somatic - etymologically from the Ancient Greek words of "σωματικός" (sōmatikós, “bodily”) and σῶμα (sôma, “body”) - is often used in biology to refer to the cells of the body in contrast to the reproductive (germline) cells, which usually give rise to the egg or sperm (or other gametes in other organisms). These somatic cells are diploid, containing two copies of each chromosome, whereas germ cells are haploid, as they only contain one copy of each chromosome (in preparation for fertilisation). Although under normal circumstances all somatic cells in an organism contain identical DNA, they develop a variety of tissue-specific characteristics. This process is called differentiation, through epigenetic and regulatory alterations. The grouping of similar cells and tissues creates the foundation for organs. Somatic mutations are changes to the genetics of a multicellular organism that are not passed on to its offspring through the germline. Most canc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNA Methylation
DNA methylation is a biological process by which methyl groups are added to the DNA molecule. Methylation can change the activity of a DNA segment without changing the sequence. When located in a gene promoter, DNA methylation typically acts to repress gene transcription. In mammals, DNA methylation is essential for normal development and is associated with a number of key processes including genomic imprinting, X-chromosome inactivation, repression of transposable elements, aging, and carcinogenesis. As of 2016, two nucleobases have been found on which natural, enzymatic DNA methylation takes place: adenine and cytosine. The modified bases are N6-methyladenineD. B. Dunn, J. D. Smith: ''The occurrence of 6-methylaminopurine in deoxyribonucleic acids.'' In: ''Biochem J.'' 68(4), Apr 1958, S. 627–636. PMID 13522672. ., 5-methylcytosineB. F. Vanyushin, S. G. Tkacheva, A. N. Belozersky: ''Rare bases in animal DNA.'' In: ''Nature.'' 225, 1970, S. 948–949. PMID 4391887. and N4- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Directionality (molecular Biology)
Directionality, in molecular biology and biochemistry, is the end-to-end chemical orientation of a single strand of nucleic acid. In a single strand of DNA or RNA, the chemical convention of naming carbon atoms in the nucleotide pentose-sugar-ring means that there will be a 5′ end (usually pronounced "five-prime end"), which frequently contains a phosphate group attached to the 5′ carbon of the ribose ring, and a 3′ end (usually pronounced "three-prime end"), which typically is unmodified from the ribose -OH substituent. In a DNA double helix, the strands run in opposite directions to permit base pairing between them, which is essential for replication or transcription of the encoded information. Nucleic acids can only be synthesized in vivo in the 5′-to-3′ direction, as the polymerases that assemble various types of new strands generally rely on the energy produced by breaking nucleoside triphosphate bonds to attach new nucleoside monophosphates to the 3′- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Base Pair
A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA and RNA. Dictated by specific hydrogen bonding patterns, "Watson–Crick" (or "Watson–Crick–Franklin") base pairs (guanine–cytosine and adenine–thymine) allow the DNA helix to maintain a regular helical structure that is subtly dependent on its nucleotide sequence. The Complementarity (molecular biology), complementary nature of this based-paired structure provides a redundant copy of the genetic information encoded within each strand of DNA. The regular structure and data redundancy provided by the DNA double helix make DNA well suited to the storage of genetic information, while base-pairing between DNA and incoming nucleotides provides the mechanism through which DNA polymerase replicates DNA and RNA polymerase transcribes DNA in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PRC2
PRC2 (polycomb repressive complex 2) is one of the two classes of polycomb-group proteins or (PcG). The other component of this group of proteins is PRC1 (Polycomb Repressive Complex 1). This complex has histone methyltransferase activity and primarily methylates histone H3 on lysine 27 (i.e. H3K27me3), a mark of transcriptionally silent chromatin. PRC2 is required for initial targeting of genomic region (PRC Response Elements or PRE) to be silenced, while PRC1 is required for stabilizing this silencing and underlies cellular memory of silenced region after cellular differentiation. PRC1 also mono-ubiquitinates histone H2A on lysine 119 (H2AK119Ub1). These proteins are required for long term epigenetic silencing of chromatin and have an important role in stem cell differentiation and early embryonic development. PRC2 are present in most multicellular organisms. The mouse PRC2 has four subunits: Suz12 (zinc finger), Eed, Ezh1 or Ezh2 (SET domain with histone methyltransferase ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a basic unit of heredity and the molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and noncoding genes. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
