Related topics: genome

Research advances emerging DNA sequencing technology

Nanopore technology shows promise for making it possible to develop small, portable, inexpensive devices that can sequence DNA in real time. One of the challenges, however, has been to make the technology more accurate.

A protein with a dual role: Both repair and mutation

Using a specialized protein, all bacteria are capable of rapidly and effectively repairing damage to their DNA from UV. However, this mutation frequency decline (Mfd) protein plays another role and causes mutations. A team1 ...

Scientists use DNA origami to monitor CRISPR gene targeting

The remarkable genetic scissors called CRISPR/Cas9, the discovery that won the 2020 Nobel Prize in Chemistry, sometimes cut in places that they are not designed to target. Though CRISPR has completely changed the pace of ...

Scientists find a way to accelerate DNA surface hybridization

Scientists globally aim to control chemical reactions—an ambitious goal that requires identifying the steps taken by initial reactants to arrive at the final products as the reaction takes place. While this dream remains ...

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DNA

Deoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms and some viruses. The main role of DNA molecules is the long-term storage of information. DNA is often compared to a set of blueprints or a recipe, or a code, since it contains the instructions needed to construct other components of cells, such as proteins and RNA molecules. The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in regulating the use of this genetic information.

Chemically, DNA consists of two long polymers of simple units called nucleotides, with backbones made of sugars and phosphate groups joined by ester bonds. These two strands run in opposite directions to each other and are therefore anti-parallel. Attached to each sugar is one of four types of molecules called bases. It is the sequence of these four bases along the backbone that encodes information. This information is read using the genetic code, which specifies the sequence of the amino acids within proteins. The code is read by copying stretches of DNA into the related nucleic acid RNA, in a process called transcription.

Within cells, DNA is organized into X-shaped structures called chromosomes. These chromosomes are duplicated before cells divide, in a process called DNA replication. Eukaryotic organisms (animals, plants, fungi, and protists) store most of their DNA inside the cell nucleus and some of their DNA in the mitochondria (animals and plants) and chloroplasts (plants only). Prokaryotes (bacteria and archaea) however, store their DNA in the cell's cytoplasm. Within the chromosomes, chromatin proteins such as histones compact and organize DNA. These compact structures guide the interactions between DNA and other proteins, helping control which parts of the DNA are transcribed.

This text uses material from Wikipedia, licensed under CC BY-SA