Figure 7: CckA drives cell fate by integrating sensory information in time and space.
From: A cell cycle kinase with tandem sensory PAS domains integrates cell fate cues
(a) Sensory domains regulate the bifunctional activity of CckA. PAS-A is required for density-dependent regulation of kinase activity on liposomes. PAS-B independently inhibits kinase function while stimulating phosphatase activity at the RD upon binding c-di-GMP. Integrating these two independent regulatory mechanisms enables a spectrum of functional states. (b) A schematic of the Caulobacter cell cycle showing the subcellular CckA surface density (orange) and the asymmetric distribution of c-di-GMP (green)37. Below the cells, coloration of a pair of boxes indicates the strength of the input signals for CckA PAS-A and PAS-B, CckA clustering at the cell poles, and the presence or absence of c-di-GMP during cell cycle progression. Processing the effects on its kinase and phosphatase activity, CckA integrates these signals to a single net activity, reflected as the downstream integrated output, shown in the CtrA∼P output box (greyscale).
