Dna Synthesis and Repair

DNA Synthesis and Repair

DNA replication or DNA synthesis is the process of copying a double-stranded DNA strand, prior to cell division. The two resulting double strands are identical if the replication went well, and each of them consists of one original and one newly synthesized strand. The process of replication consists of three steps, initiation, replication and termination.

A newly discovered enzyme is believed to play a key role in maintaining the integrity of a cell's genetic information - the basis by which the life of a cell or species is preserved - by allowing its DNA to be replicated despite discovery of a mishap on the sequence that it corrects with a new mistake. In the paper posted on the Web site of The EMBO Journal, an official journal of the European Molecular Biology Organization, the researchers describe how DNA polymerase Q, or POL-Q, has the exceptional ability to bypass damaged spots in the DNA sequence that are caused by a cell's normal wear and tear or other abuses. In addition, it is the only known enzyme that orchestrates not only one, but two steps involved in bypassing common types of DNA damage.

There are many causes of DNA damage - the sun's ultraviolet rays, environmental toxins, radiation from X-rays or agents in chemotherapy - and the source determines which enzyme is involved and its technique for repair.

Medical News Today. (2004) New DNA repair enzyme makes mistakes to save lives of cells. University of Pittsburgh Medicine. Retrieved September 17, 2006 from http://www.medicalnewstoday.com/medicalnews.php?newsid=15317