BioProject

A conserved regulatory pathway directs developmental transitions and asymmetries in Agrobacterium tumefaciens. More...

A conserved regulatory pathway directs developmental transitions and asymmetries in Agrobacterium tumefaciens. Core components of this coordination of division and development (CDD) pathway include two integrated phosphorelays. One of these phosphorelays includes at least four histidine sensor kinase homologues, DivJ, PleC, PdhS1, and PdhS2, and at least two response regulators, DivK and PleD. Previously we demonstrated that PdhS2 reciprocally regulates biofilm formation and swimming motility. In the current study we further dissect the architecture of the CDD pathway in A. tumefaciens with respect to PdhS2. We show that PdhS2-dependent effects on attachment and motility require the response regulator, DivK, but do not require PdhS2 autokinase or phosphotransfer activities. We also demonstrate that PdhS2 regulation of biofilm formation is dependent upon multiple diguanylate cyclases, including PleD, DgcA, and DgcB, implying that PdhS2 regulation of this process intersects with pathways regulating levels of the second messenger cyclic-di-GMP. Finally, we show that upon cell division a GFP fusion to PdhS2 dynamically localizes to the new pole of the bacterium suggesting that PdhS2 controls processes in the daughter cell compartment of predivisional cells. These observations suggest that PdhS2 negatively regulates DivK, and possibly PleD, activity to control developmental processes in the daughter cell compartment of predivisional cells, as well as in newly released motile daughter cells. Overall design: Three biological replicates, independent RNA preparations, one dye swap. Less...