However, except for the fact that they are not necessary for target gene expression (Adhikari & Novick, 2008), the role of these two proteins is completely unknown.Figure 1MBP-SaeS does not show detectable phosphatase activityPreviously, we observed that phosphorylated SaeR (P-SaeR) has a long half-life (over 4 h), even in the presence of the cytoplasmic domain of SaeS (SaeSc), (Sun et al., 2010b)