CpGmotief

CpGmotief refers to a CpG dinucleotide sequence in DNA, where a cytosine (C) is immediately followed by a guanine (G) in the 5' to 3' direction. These sequences are often found in clusters, known as CpG islands, which are typically located in or near the promoter regions of genes. In mammals, CpG dinucleotides are frequently methylated, a process catalyzed by DNA methyltransferases. This methylation usually occurs on the cytosine residue.

The methylation of CpG motifs plays a crucial role in gene regulation. Unmethylated CpG islands are generally associated with active gene transcription. Conversely, methylation within CpG islands often leads to gene silencing, as it can inhibit the binding of transcription factors or recruit proteins that promote a condensed chromatin structure. This epigenetic modification is heritable through cell division and is essential for various biological processes, including embryonic development, X-chromosome inactivation, and the suppression of transposable elements.

Aberrant CpG methylation patterns are implicated in several diseases, most notably cancer. Hypermethylation of CpG islands in tumor suppressor gene promoters can silence these genes, contributing to uncontrolled cell growth and tumor formation. Conversely, hypomethylation of certain genomic regions can lead to genomic instability. Understanding CpG motif methylation is therefore vital for both fundamental biological research and the development of diagnostic and therapeutic strategies for disease.