DNA Binding of the Cell Cycle Transcriptional Regulator GcrA Depends on N6-Adenosine Methylation in Caulobacter crescentus and Other Alphaproteobacteria
Figure 6
CcrM and GcrA dependence of selected promoters.
(A) Immunoblots showing that the ΔccrM mutation does not affect the steady-state levels of the master cell cycle regulators, GcrA, CtrA and DnaA using polyclonal antibodies to these proteins. (B) GcrA-depletion impairs PmipZ-, PpodJ-, PflaY - and PpleC-lacZ activity, while affecting PCCNA_00697-lacZ to a lesser extent. β-Galactosidase activities were measured in the WT or the GcrA depletion strain harbouring the transcriptional reporters after growth in PYE supplemented with xylose (0.3%) or glucose (0.2%) for 5 hours and tetracycline to select for the reporter plasmid. (C) Mutation of the CcrM recognition sites (GAnTC→GCnTC) cripples PmipZ-, PpodJ-, PflaY - and PpleC-lacZ activity, but not PCCNA_00697-lacZ. WT cells harbouring the reporter plasmids were grown PYE and tetracycline to select for the reporter plasmid.