DNA RNA strands are created using DNA strands as a template in a process called transcription. Under the genetic code, these RNA strands specify the sequence of amino acids within proteins in a process called translation. Within eukaryotic cells, DNA is organized into long structures called chromosomes. Before typical cell division, these chromosomes are duplicated in the process of DNA replication, providing a complete set of chromosomes for each daughter cell. Eukaryotic organisms (animals, plants, fungi and protists) store most of their DNA inside the cell nucleus and some in organelles, such as mitochondria or chloroplasts. In contrast, prokaryotes (bacteria and
Epigenetics in stem-cell differentiation one. "DNMT3A" and "DNMT3B" have both been linked to a role in the establishment of DNA methylation pattern in the early development of the stem cell, whereas "DNMT1" is required to methylate a newly synthesized strand of DNA after the cell has undergone replication in order to sustain the epigenetic regulatory state. Numerous proteins can physically interact with "DNMTs" themselves, which help target "DNMT1" to hemi-methylated DNA. Several new studies point to the central role of DNA methylation interacting with the regulation of cell cycles and DNA repair pathways in order to maintain the undifferentiated state. In embryonic stem cells,