Figure 9. G3BP1-C_term fragment reduces SG formation and enhances CVB3 replication.

<p>(A, B) HeLa cells were co-transfected with pEGFP-G3BP1 and either FLAG-G3BP1-N_term (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0079546#pone.0079546.s003" target="_blank">Figure S3</a>) or FLAG-G3BP1-C_term for 48 hrs, followed by sham- or CVB3-infection at an MOI of 10 for the indicated time points. G3BP1-C_term and G3BP1-N_term were stained using an anti-FLAG antibody. Arrow heads indicate cells expressing high levels of G3BP1-C_term but lacking distinct G3BP1(+)-SGs or poly-(A) granules. Cells treated with arsenite (50 mM) for 1 hr were used as positive controls. (C) Quantitation of GFP-G3BP1 foci and poly-A granules from (A and S3A) and (B and S3B) at 3 hr pi, respectively. Quantification was performed by counting cells expressing, empty vector, GFP-G3BP1-SGs or poly-A granules together with FLAG, and dividing by the total number of cells expressing FLAG. Results are presented as mean ± SD (n = 5 images), #p<0.001. N.D., No statistical difference. (D) HeLa cells were co-transfected with pEGFP-G3BP1 and FLAG-G3BP1-C_term for 48 hrs, and then treated with 50 mM arsenite for 1 hr. Immunostaining was conducted and representative images are displayed. (E) Quantitation of GFP-G3BP1 SGs from (D). The data is presented as mean ± SD (n = 5 images), #p<0.001. (F) Plaque assay was performed to assess the effect of G3BP1-C_term expression on CVB3 replication. Results are presented as relative PFU/ml. The value of the empty vector control was arbitrarily set as 1. The data is presented as mean ± SD (n = 3), #p<0.001.