Figure 13.

Increased nuclear expression of cell stress marker STI1 corresponding with Wld^s expression in HEK293 cells. Confocal micrographs of HEK293 cells transfected with either an (a-f) enhanced green fluorescent protein (eGFP)-Wld^s construct or an (g-i) eGFP alone control construct. Stress induced phosphoprotein 1 (STI1) is shown in red, the nuclear marker TOPRO3 is shown in blue, and Wld^s protein in green (panels a, d and g show STI1 and TOPRO3; panels b, e and h show construct and TOPRO3; and c, f and i show all three markers). Note how STI1 protein can be seen in nuclear puncta with high frequency where Wld^s is being expressed, but was never observed in non-Wld^s-expressing cells. The majority of Wld^s puncta coincided with STI1 puncta. Nuclear puncta of STI1 were never observed in eGFP transfected control cells (panels g-i). Scale bar = 10 μm.