 |
 |
 |
 |
 |
 |
Merck-MIT Postdoctoral Fellow
We have initially focused the studies on the strand breaks and abasic sites arising from deoxyribose oxidation in DNA, a type of DNA damage caused by γ-radiation and the antibiotics neocarzinostatin and calicheamicin. The strand breaks and abasic sites contain aldehyde and ketone moieties that can be labeled with biotin and derivatized as stable oximes by reaction with a biotinylated hydroxylamine reagent, the aldehyde reactive probe (ARP). By using biotin labeled immunoprecipitation and ligation-mediated polymerase chain reaction, we are able to isolate and amplify the damaged DNA fragments. To help identify these fragments, the amplified products are then probed on to a tiled yeast oligonucleotide array. Finally we will localize damage sites using an existing computational framework for the genomes of S. cerevisiae and correlate the sites to variety of genomic features, including genes and their expression patterns, predicted promoter elements and chromosomal structures.
|
Reactive oxygen species
like superoxide, hydrogen peroxide, and hydroxyl radicals areinevitably
formed during oxygen metabolism especially from the incomplete
reduction of oxygen in mitochondria. In addition, reactive
nitrogen species like nitrogen dioxide, nitrogen monoxide and
peroxynitrite can be formed in vivo with widely different
reactivities. All these toxic species are able to cause damage to
proteins, lipids and DNA that lead to oxidative and nitrosative stress
implicated to cancer and aging. The most significant damage is
thought to be DNA modifications that cause mutations and genomic
instability. Therefore, one of the major challenges in chemical
carcinogenesis and genetic toxicology would be to define the
relationship between DNA damage and associated mutations or cell
death. Central to this relationship are various factors that
determine both the location and quantity of DNA damage arising in cells
and the corresponding cellular response. While the location of
DNA lesions is thought to be important for cellular response, we know
little about what affects damage location other than the fact that
genotoxic agents do not damage DNA randomly in cells. To better
identify such determinants, we have developed a project to map sites of
DNA damage across the genome of S. cerevisiae and then
correlate the damage locations with features of genomic organization
and nuclear architecture. The basic approach is shown in Fig. 1.Lab Members | Research Projects | Publications | Links | Contact Us | Home Copyright
© 2004 Massachusetts Institute of Technology. All Rights Reserved. |