Identification of GRP75 as a novel PreS1 binding protein using a proteomics strategy

Cui, LunbiaoGe, YiyueQi, YuhuaShi, ZhiyangJiao, YongjunQi, XianZhai, XiangjunWang, Hua

The PreS1 region of the L protein is important in cell attachment and consequently in hepatitis B virus (HBV) infectivity. To identify novel PreS1 interacting protein, we performed Glutathione-S-transferase (GST) pull-down, two-dimensional gel electrophoresis (2-DE) and mass spectrometry assays. Glucose-regulated proteins (GRP) 78 and 75 were found to bind PreS1. The interactions between PreS1 and GRP75 were confirmed by a co-immunoprecipitation experiment. GRP78 and GRP75 may play important roles in mediating HBV virion entering into hepatocyte and regulating proper folding of the L protein due to their critical functions in protein folding and trafficking. The finding of novel PreS1 binding protein enriches our knowledge about molecular mechanism of HBV infection.

1. PreS1
2. Proteomics
3. HBV
4. GRP75