The ATF6 branch of unfolded protein response and apoptosis are activated to promote African swine fever virus infection

Galindo, I; Hernáez, B; Muñoz-Moreno, R; Cuesta-Geijo, M A; Dalmau-Mena, I; Alonso, C

Calnexin is an ER resident molecular chaperone that has a key role in the correct folding of membrane proteins. It has been proposed that calnexin acts as a scaffold for caspase 8-dependent cleavage of the ER transmembrane protein Bap31 and thus for the generation of the pro-apoptotic p20 under ER stress. 27 The Bap31 p20 fragment directs proapoptotic crosstalk between the ER and mitochondria. 28 To study whether overexpression of calnexin during the infection is involved in the cleavage of Bap31, we monitored p20 by western blot. Bap31 remained intact during the infection, thereby indicating the absence of pro-apoptotic signals between the ER and mitochondria (Figure 4a ).