Real-time imaging nuclear translocation of Akt1 in HCC cells

Biochem Biophys Res Commun. 2007 May 18;356(4):1038-43. doi: 10.1016/j.bbrc.2007.03.092. Epub 2007 Mar 26.

Abstract

Akt is one of the critical mediators in cellular signaling, and overactivation of Akt related pathway frequently occurs in hepatocellular carcinoma (HCC). In this study, we presented that Akt was upregulated in HCC cell lines, and its active phosphorylated form was mainly located in the nucleus. Employing the laser confocal techniques for imaging intracellular protein dynamics, we monitored the transnuclear movement of GFP-tagged wild-type Akt1 (Akt1-WT-GFP) and its inactive mutant (Akt1-T308A/S473A-GFP) in live SMMC-7721 HCC cells, and both of fusion proteins were found to distribute over the cytoplasm and nucleus. Moreover, it was found that platelet derived growth factor (PDGF) was able to accelerate the nuclear translocation of wild-type Akt1 in HCC cells but failed to speed up the motion of the mutant. It was demonstrated that activation of phosphatidylinositol 3-kinase (PI3K) and Akt1 facilitated the nuclear translocation of Akt1, but the phosphorylation at threonine 308 and serine 473 was not prerequisite.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Active Transport, Cell Nucleus*
  • Carcinoma, Hepatocellular / metabolism*
  • Carcinoma, Hepatocellular / pathology*
  • Cell Line, Tumor
  • Computer Systems
  • Humans
  • Liver Neoplasms / metabolism*
  • Liver Neoplasms / pathology*
  • Microscopy, Confocal / methods*
  • Microscopy, Fluorescence / methods
  • Proto-Oncogene Proteins c-akt / metabolism*

Substances

  • AKT1 protein, human
  • Proto-Oncogene Proteins c-akt