A critical role of heat shock cognate protein 70 in Apoptin-induced phosphorylation of Akt

Apoptin, a protein from chicken anemia virus, selectively induces apoptosis of transformed or tumor cells, but not in normal cells. However, the mechanism of action of Apoptin is still not well understood. Using yeast two-hybrid and immunoprecipitation approaches, we found that Apoptin interacted with Heat shock cognate protein 70 (Hsc70). In vivo, Apoptin induced the translocation of endogenous Hsc70 from the cytoplasm to the nucleus, and both were co-localized in the nucleus. In addition, Apoptin induced Akt phosphorylation, which was markedly inhibited by Hsc70 knockdown, suggesting that Hsc70 may play a critical role in Apoptin-induced Akt phosphorylation. These findings help to further understand the molecular mechanism of Apoptin.

► Apoptin selectively induces apoptosis of transformed or tumor cells.
► We found Apoptin interacted with endogenous Hsc70.
► Apoptin expression induced translocation of Hsc70 from the cytoplasm to the nucleus.
► Knockdown Hsc70 inhibited Apoptin-induced Akt phosphorylation.