Down‐regulation of human RNA/DNA helicase SUV3 induces apoptosis by a caspase‐ and AIF‐dependent pathway

Abstract

Background information . The nuclear gene hSUV3 (human SUV3 ) encodes an ATP‐dependent DNA/RNA helicase. In the yeast Saccharomyces cerevisiae the orthologous Suv3 protein is localized in mitochondria, and is a subunit of the degradosome complex which regulates RNA surveillance and turnover. In contrast, the functions of human SUV3 are not known to date. Results . In the present study, we show that a fraction of human SUV3 helicase is localized in the nucleus. Using small interfering RNA gene silencing in HeLa cells, we demonstrate that down‐regulation of hSUV3 results in cell cycle perturbations and in apoptosis, which is both AIF‐ and caspase‐dependent, and proceeds with the induction of p53. Conclusions . In addition to its mitochondrial localization, human SUV3 plays an important role in the nucleus and is probably involved in chromatin maintenance.