Flavivirus including dengue are ER tropic and cause the ER to initiate stress response signaling.24 To ascertain the activation of ER stress, we examined expression of the chaperone protein calreticulin, a marker of global ER stress.24, 25 Calreticulin has been used as a positive indicator of ER stress in various cell types and model organisms.26, 27, 28, 29, 30, 31, 32 106 MDCK (Madin Darby canine kidney cell line) cells were infected with dengue virus (multiplicity of infection (MOI)=5) for 24 h and were then lysed for protein extraction and western blotting. The gene discussed is CALR; the disease is infection.