DNA Repair

Jamshed Arslan, Pharm D, PhD

By Natalia Gurule, PhD

Ataxia Telangiectasia Mutated (ATM) is a serine/threonine protein kinase that is the master regulator of the DNA double-strand break (DSB) repair pathway. ATM is a key part of the cell cycle machinery that activates checkpoint signaling in response to DSBs, apoptosis, and genotoxic insults. ATM normally exists in its inactive state as a dimer or tetramer - upon DNA damage, it dissociates into monomers triggered by its own autophosphorylation.

Apurinic/apyrimidinic (AP) endonuclease 1 (APE1) plays an important role in the DNA base excision repair pathway.

NBS1 (Nijmegen breakage syndrome protein 1) is a component of the MRN complex (Mre11-Rad50-Nbs1) that plays important role in detecting DNA double strand breaks (DSBs) and triggering the downstream cascade. DSBs can be caused by ionizing radiation, chemotherapy drugs, metabolic ROS, replication errors, programmed enzymatic activities during meiosis/V(D)J recombination, etc.

APE1 is involved in repairing oxidative DNA damages in vitro, regulates the redox of transcriptional factors, repairs AP sites in DNA, and is important for embryonic development in mice. Learn more about APE1 in our infographic below.

Novus Biologicals offers APE1 reagents for your research needs including:

An AP (apurinic/apyrimidinic) site, also known as an abasic site, is a region of DNA that is lacking a purine or pyrimidine base. This can occur spontaneously, or as a result of DNA damage. When DNA damage occurs, DNA repair pathways are activated.

8-hydroxyguanine is a form of oxidative DNA damage where free radicals cause G:C to T:A transversions within the backbone. In E. coli, three DNA repair enzymes exist to prevent the mutagenic effects of 8-hydroxyguanine mutations. One of these enzymes, Ogg1, was found to have both functional yeast (yOgg1) and human (hOgg1) homologues. These hOgg1 proteins efficiently release the 8-hydroxyguanine through cleavage.

In the United States, breast cancer is one of the most common cancers and the second leading cause of cancer related deaths in women. According to the American Cancer Society's most recent estimates for breast cancer in the United States, there are about 200,000 new cases of invasive breast cancer, 60,000 new cases of carcinoma in situ (CIS),  and approximately 40,000 deaths from breast cancer this year.