Figure 3.

ERK5 S496 phosphorylation is critical for IR-induced EC inflammation. HUVECs were co-transfected with the NF-κB-Luc luciferase reporter vector and the pRL-CMV vector (renilla luciferase activity, internal control) together with the expression vector encoding the flag-tagged ERK5 wild type (WT) or the S496A mutant. Transfected cells were then exposed to gamma radiation (2 Gy) and harvested after 24 h. (A) NF-κB activation was quantified by measuring relative luciferase activity using a dual-luciferase reporter system. Shown are relative luciferase activity, presented as firefly luciferase/renilla luciferase activity ratio. (n = 6) (B) VCAM1 expression was determined by measuring percentage of positive VCAM1-staining cells using the BD Accuri C6 Flow Cytometer system using the FL1 533/30 nm filter. (n = 5)