Figure 6.
Ephrin-B2 mediates EZH2 enhancement of KSHV-induced tubule formation in endothelial cells. A and B, Knockdown of either Ephrin-B2 or EZH2 inhibits cell growth and tubule formation in KSHV-infected BOEC (A) and SLKp (B) cells. Mock or KSHV-infected BOEC cells were transduced with lentivirus of EZH2 shRNA, 3 pooled Ephrin-B2 shRNAs or control shRNA for 4 days and examined for cell growth by directly counting of cell number on the phase contrast images (upper panel). Transduced cells were also serum-starved for 12 h and examined for the tubule formation on Matrigel in full medium. Representative images of tubule formation (second panel) were taken at 7 h post-plating and quantified for tubule length (third panel). Cells were examined for the expression of EZH2 and Ephrin-B2 proteins at day 4 lentivirus post-transduction (lower panel). Experiments with SLKp cells were carried out as the BOEC cells except cells were not subjected to serum starvation before the tubulogenesis assay.