Dynamical Localization of DivL and PleC in the Asymmetric Division Cycle of Caulobacter crescentus: A Theoretical Investigation of Alternative Models
Fig 6
Swarmer-to-stalked transition is uncoupled from G1-to-S transition in DivL mislocalization mutants.
Concentration gradients are color coded as in Fig 5. (A) DivL is uniformly distributed at all times in the cell cycle. Even though PleC transitions to a kinase, DivL remains deactivated (bound to DivK~P) in the predivisional cell, resulting in no gradient of CtrA~P. (B) DivL (and CckA) are localized at the old pole (t = 0–90 min), before switching to the new pole in the predivisional cell (t = 90–120 min). Even after PleC transitions to a kinase, DivL is not deactivated in stalked cells, delaying the dephosphorylation of CtrA~P until PleC delocalizes from the old pole (at t = 50 min). (C) DivL and PleC are co-localized at one of the poles during all stages of the cell cycle. Hence, CtrA is phosphorylated through all stages of the cell cycle (G1-arrest).