Signal transduction of gap junctional genes, connexin32, connexin43 in human hepatocarcinogenesis

Figure 4 Western blot analysis of phosphorylation on tyrosine of CX32, CX43 proteins in various cells lines. Cells were harvested and lysed, equal amount of cell lystates were resolved of SDS-PAGE, transferred to NC membranes, and then probed with anti-phophorylation tyrosine mAb 4G10. (A). Expressions of CX32 proteins in cell lines with special anti-CX32 mAb. CX32 showed high immunoblot signal only in normal hepatocyte cell line QZG with very slight signal in hepatocarcinoma cell lines HHCC, SMMC-7721. (B). Expressions of CX43 proteins in cell lines with special anti-CX43 mAb. CX43 apperared in both QZG and SMMC-7721 cells but no in HHCC. (C). Phosphorylation on tyrosine of CX43 with special anti-phosphrylation tyrosine 4G10, unphosphorylation appeared in QZG cells even they showed high level expression of CX32, CX43. (D). Phosphorylated tyrosine of CX43 protein was detected in SMMC-7721 cells.