BAK1 and cytomegalovirus infection: Although CMV infection stimulates PTI, no marked increases in CMV accumulation were seen in bak1 mutant plants (Figure S1), which contrasts with work with certain other viruses, where a mutation in BAK1 will result in increased virus accumulation, showing that PTI plays a role in limiting their multiplication (Kørner et al., 2013; Nicaise & Candresse, 2017; Niehl et al., 2016; Yang et al., 2010; Zorzatto et al., 2015).