Title:Fibrinogen Alpha Chain Acts as a HBsAg Binding Protein and their Interaction Promotes HepG2 Cell Apoptosis
VOLUME: 11 ISSUE: 1
Author(s):Ping Li, Li Xiao, Ying-Ying Li, Xu Chen, Chuan-Xing Xiao, Jing-Jing Liu, Xiao-Ning Yang, Amarsanaa Jazag, Jian-Lin Ren and Bayasi Guleng
Affiliation:Department of Gastroenterology, Zhongshan Hospital affiliated with Xiamen University, 201 Hubin South Road, Xiamen, Fujian Province, China 361004.
Keywords:Binding protein, FGA, HBs, HepG2 cell apoptosis.
Abstract:Background and Aims: Our previous yeast two-hybrid screening data showed the Fibrinogen alpha chain (FGA) as one
of the candidate binding proteins of S regional of the HBsAg (HBs). In this study, we aimed to define that FGA is a binding
protein of HBs and to determine its function in Hepatocellular carcinoma (HCC) tumorigenesis.
Methods: The binding and co-localization between HBs and FGA were confirmed using co-immunoprecipitation and
confocal microscopy was employed flow cytometry to analyze cell apoptosis. The involved mechanisms were investigated
using protein array and western blot.
Results: Our results indicated that FGA is a binding protein of HBs and is co-localized in the cytoplasm in vitro. Interaction
between HBs and FGA significantly induced apoptosis in HepG2 cells. Moreover, knockdown of the FGA protein
decreased the expression levels of the pro-survival factors Bcl-XL and Mcl-1, increased the expression of the proapoptotic
proteins, and decreased the phosphorylation levels of Akt in this cell.
Conclusion: FGA is a binding protein of HBs and their interaction induced the apoptotic capacity of HepG2 cells, suggesting
the interactions between viral and host cell proteins are involved in the development of virus-related hepatitis or
HCC.
