FIG 8.

Regulation of the interactions of G3BP1 with other SG proteins under stress conditions. (A) The FLAG-tagged WT G3BP1 expression construct or vector control was transfected into 293T cells. Two days later, the cells were either left untreated or were treated for 30 min or 1 h with 0.5 mM sodium arsenite in the medium, followed by FLAG immunoprecipitation and immunoblotting with the indicated antibodies. Representative images of three repetitions are shown. (B) The FLAG-tagged WT, K376Q, or K376R G3BP1 expression construct or vector control was transfected into 293T cells. Two days later, the cells expressing FLAG-G3BP1 were treated for 1 h with 0.5 mM sodium arsenite in the medium, followed by 5 h of recovery without sodium arsenite in the presence of deacetylase inhibitors (DACi). The cells were lysed and FLAG immunoprecipitations were performed, followed by immunoblotting with the indicated antibodies. Under the top panel, the relative quantification of the coprecipitated PABP1 protein is shown from three repetitions. Only the coprecipitation of PABP1 with WT or K376Q G3BP1 was statistically significantly different (see the text for details). Ext, total cell extracts.