Effect of Soluble Fibronectin on Protein Kinase A Activation in SGC-7901

Abstract: To investigate the effect of soluble fibronectin on protein kinase A activation in gastric cancer cell line SGC-7901， we treated Gastric cancer cell line SGC-7901 with soluble fibronectin of different concentrations or different time， expression of PKA catalytic subunit and the phosphorylation level of vasodilator-stimulated phosphoprotein (VASP)， one of PKA substrates were determined by Western blot， the distribute of p-VASP was determined by immumofluorescence method. The results revealed that， FN can inhibit the PKA activation in SGC- 7901 among concentrations of 0.5~8 μg/ml. As the dose and time increased， the inhibitory of FN on PKA activation of SGC-7901 was significantly increased after 12 h. FN mediate p-VASP accumlate on the edge of cell. However， these effect disapper in stably transfected SGC cells expressing the AKAP inhibitory peptide Ht31. These data suggest that PKA activation in SGC-7901 could be inhibited by FN， the inhibition determined by FN concentration， functionary time and PKA anchor. FN mediate localized activation of PKA.

CSTR: 32200.14.cjcb.2011.05.0006