Down-regulation of human RNA/DNA helicase SUV3 induces apoptosis by a caspase- and AIF-dependent pathway.
BACKGROUND
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.
Szczesny
Roman J
RJ
Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106 Warsaw, Poland.
Obriot
Helene
H
Paczkowska
Aleksandra
A
Jedrzejczak
Robert
R
Dmochowska
Aleksandra
A
Bartnik
Ewa
E
Formstecher
Pierre
P
Polakowska
Renata
R
Stepien
Piotr P
PP
D017209:Apoptosis; D051033:Apoptosis Inducing Factor / Q000378:metabolism*; D020169:Caspases / Q000378:metabolism*; D002453:Cell Cycle; D002467:Cell Nucleus / Q000201:enzymology; D053487:DEAD-box RNA Helicases / Q000235:genetics* / Q000378:metabolism; D004265:DNA Helicases / Q000235:genetics*; D015536:Down-Regulation / Q000235:genetics*; D015971:Gene Expression Regulation, Enzymologic; D020868:Gene Silencing; D006367:HeLa Cells; D006801:Humans; D008928:Mitochondria / Q000201:enzymology; D021381:Protein Transport; D034741:RNA, Small Interfering / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
D051033:Apoptosis Inducing Factor; D034741:RNA, Small Interfering; D016159:Tumor Suppressor Protein p53; D020169:Caspases; C469673:SUPV3L1 protein, human; D004265:DNA Helicases; D053487:DEAD-box RNA Helicases