I-motif DNA I-motif DNA i-motif DNA is a type of deoxyribonucleic acid, discovered in 2018, that is found in the nuclei of human cells. An abbreviation of intercalated motif, the four-strand i-motif is unlike the iconic double helix DNA. I-motifs are four-stranded quadruplex structures formed by cytosine-rich DNA, similar to the G-quadruplex structures that guanine-rich DNA forms. C-rich DNA regions are common in gene regulation portions of the genome. Recently, i-motifs were discovered in human cells and were shown to play a role in cell reproduction. I-motifs have potential applications in nanotechnology and nanomedicine due to their unique pH sensitivity and have
DNA methylation DNA methylation polymorphisms are monocytes and lymphocytes, which experience an overall hypomethylation. One proposed mechanism behind this global hypomethylation is elevated homocysteine levels causing hyperhomocysteinemia, a known risk factor for cardiovascular disease. High plasma levels of homocysteine inhibit DNA methyltransferases, which causes hypomethylation. Hypomethylation of DNA affects gene that alter smooth muscle cell proliferation, cause endothelial cell dysfunction, and increase inflammatory mediators, all of which are critical in forming atherosclerotic lesions. High levels of homocysteine also result in hypermethylation of CpG islands in the promoter region of the estrogen receptor alpha (ERα) gene, causing its down regulation. ERα protects against