Within Orai1, mutational analysis and domain swap experiments between Orai isoforms have implicated the cytosolic domains, in particular the Orai1 N- and the C-termini (Lee et al., 2009; Srikanth et al., 2010; Frischauf et al., 2011; Mullins et al., 2016b) in CDI. Here, ORAI1 is linked to clostridium difficile infection.