DNA
hideDeoxyribonucleic 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.
For more information about DNA, read the full article at
Wikipedia.
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News tagged with dna
DNA molecules in moss open door to new biotechnology
Nov 06, 2009 |
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Plasmids, which are DNA molecules capable of independent replication in cells, have played an important role in gene technology. Researchers from Uppsala University in Sweden have now demonstrated that plasmid-based methods, ...
Nanoparticles may cause DNA damage across a cellular barrier
Nanotechnology / Bio & Medicine
Nov 05, 2009 |
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(PhysOrg.com) -- Scientists have shown in the laboratory that metal nanoparticles damaged the DNA in cells on the other side of a cellular barrier. The research, by the University of Bristol, is published ...
Complete Genomics reports low-cost sequencing of 3 human genomes
Nov 05, 2009 |
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Complete Genomics, a third-generation human genome sequencing company, today announced publication of a report in the journal Science describing its proprietary DNA sequencing platform, including analysis of seq ...
Genetic tests for UK asylum seekers draw criticism
Nov 05, 2009 |
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(AP) -- Britain is using genetic tests on some African asylum seekers in an effort to catch those who are lying about their nationality, drawing criticism from scientists and provoking outrage from rights ...
Scientists reveal how induced pluripotent stem cells differ from embryonic stem cells
Nov 05, 2009 |
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The same genes that are chemically altered during normal cell differentiation, as well as when normal cells become cancer cells, are also changed in stem cells that scientists derive from adult cells, according to new research ...
Survival of the healthiest: Selective eradication of malignant cells
Nov 05, 2009 |
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The ultimate goal in cancer research, a treatment that kills cancer cells whilst leaving healthy cells untouched, is brought nearer by the success of a new therapeutic approach. The potential therapy, published in BioMed ...
DNA 'barcode' for tropical trees
Nov 04, 2009 |
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In foods, soil samples or customs checks, plant fragments sometimes need to be quickly identified. The use of DNA “barcodes” to itemize plant biodiversity was proposed during the 1992 Rio de Janeiro Summit. ...
Scientists launch effort to sequence the DNA of 10,000 vertebrates
Nov 04, 2009 |
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Scientists have an ambitious new strategy for untangling the evolutionary history of humans and their biological relatives: Create a genetic menagerie made of the DNA of more than 10,000 vertebrate species. The plan, proposed ...
Taking aim at mysterious DNA structures in the battle against cancer
Nov 04, 2009 |
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Designers of anti-cancer drugs are aiming their arrows at mysterious chunks of the genetic material DNA that may play a key role in preventing the growth and spread of cancer cells, according to an article in the current ...
X-ray named top achievement by British museum
Nov 04, 2009 |
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The X-ray was named the most important modern scientific achievement Wednesday in a poll conducted for Britain's Science Museum, beating Apollo spacecraft and DNA.
Nanostructured Integrated Circuit Detects Type and Severity of Cancer
Nanotechnology / Bio & Medicine
Nov 03, 2009 |
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(PhysOrg.com) -- A team of investigators from the University of Toronto have used nanomaterials to develop an inexpensive microchip sensitive enough to quickly determine the type and severity of a patient's cancer so that ...
Research study on the European mink, Mustela lutreola
Nov 02, 2009 |
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The European mink, Mustela lutreola, is a species catalogued as in danger of extinction, due to the large decline in their population over the past century. It is considered to be one of the most endangered mammals, both l ...
Researchers sequence swine genome
Nov 02, 2009 |
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(PhysOrg.com) -- A global collaborative has produced a first draft of the genome of a domesticated pig, an achievement that will lead to insights in agriculture, medicine, conservation and evolution.
'Moonlighting' molecules discovered
Oct 29, 2009 |
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Since the completion of the human genome sequence, a question has baffled researchers studying gene control: How is it that humans, being far more complex than the lowly yeast, do not proportionally contain in our genome ...
Researchers use drug-radiation combo to eradicate lung cancer
Oct 29, 2009 |
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Researchers at UT Southwestern Medical Center have eliminated non-small cell lung (NSCL) cancer in mice by using an investigative drug called BEZ235 in combination with low-dose radiation.
