Short interfering RNA-mediated silencing of glutaredoxin 2 increases the sensitivity of HeLa cells toward doxorubicin and phenylarsine oxide

AUTOR(ES)

Lillig, Christopher Horst

FONTE

National Academy of Sciences

RESUMO

Glutaredoxin (Grx) belongs to the thioredoxin fold superfamily and catalyzes glutathione-dependent oxidoreductions. The recently discovered mitochondrial and nuclear Grx (Grx2) differs from the more abundant cytosolic Grx (Grx1) by its higher affinity toward S-glutathionylated proteins and by being a substrate for thioredoxin reductase. Here, we have successfully established a method to silence the expression of Grx2 in HeLa cells by using short interfering RNA to study its role in the cell. Cells with levels of Grx2 <3% of the control were dramatically sensitized to cell death induced by doxorubicin/adriamycin and phenylarsine oxide but did not show signs of a general increase in oxidative damage with respect to carbonylation and glutathionylation. The ED50 for doxorubicin dropped from 40 to 0.7 μM and for phenylarsine oxide from 200 to 5 nM. However, no differences were detected after treatment with cadmium, a known inhibitor of Grx1. These results indicate a crucial role of Grx2 in the regulation of the mitochondrial redox status and regulation of cell death at the mitochondrial checkpoint.

Documentos Relacionados

• Short interfering RNA-mediated interference of gene expression and viral DNA accumulation in cultured plant cells
• Insulin signaling through Akt/protein kinase B analyzed by small interfering RNA-mediated gene silencing
• Double-stranded RNA-mediated gene silencing in fission yeast
• Thioredoxin, glutaredoxin, and thioredoxin reductase from cultured HeLa cells.
• Gene silencing without DNA. rna-mediated cross-protection between viruses