CPG ISLAND Meaning and
Definition
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A CpG island refers to a DNA sequence in the genome of organisms, particularly vertebrates, characterized by a higher-than-expected frequency of cytosine (C) and guanine (G) nucleotides occurring adjacent to each other. These islands often span several hundred base pairs and are primarily found in the promoter regions of genes. CpG islands are named so because the sequence consists of a cytosine nucleotide followed by a guanine nucleotide, connected by a phosphate group (CpG).
The distinct feature of CpG islands is their high density of CpG dinucleotides, which are usually scarce in the genome due to methylation, a process in which a methyl group (-CH3) is added to the DNA molecule. CpG islands, however, tend to be relatively unmethylated, contributing to their functional importance. They are associated with gene regulation and are frequently found near the transcription start sites of genes. Methylation of CpG islands can silence gene expression, so their low methylation status allows for the recruitment of transcription factors and other regulatory proteins to bind to the DNA, promoting gene expression.
CpG islands also play a role in epigenetics, the study of heritable changes in gene expression that do not involve alterations in the DNA sequence itself. By participating in the regulation of gene activity, CpG islands are crucial for a wide range of biological processes, including embryonic development, tissue-specific gene expression, and disease conditions such as cancer.
Common Misspellings for CPG ISLAND
- xpg island
- vpg island
- fpg island
- dpg island
- cog island
- clg island
- c0g island
- cpf island
- cpv island
- cpb island
- cph island
- cpy island
- cpt island
- cpg usland
- cpg jsland
- cpg ksland
- cpg osland
- cpg 9sland
- cpg 8sland
- cpg ialand
Etymology of CPG ISLAND
The term "CpG island" is a compound term that originated in the field of molecular biology. Here is the breakdown of its etymology:
1. CpG: This part of the term refers to the specific sequence of nucleotides found in DNA. In molecular biology, CpG refers to the cytosine (C) followed by a guanine (G) connected by a phosphodiester bond. The "p" represents the phosphodiester bond linking the two nucleotides together.
2. Island: It refers to a specific region or segment of DNA. In the context of CpG islands, it signifies a distinct area of DNA that contains a high density of CpG sites relative to its surrounding regions.
Therefore, the term "CpG island" combines these two components to describe a region of DNA defined by a high density of CpG sites.
