Article

The architecture and conservation pattern of whole-cell control circuitry

Department of Developmental Biology, Stanford University School of Medicine, Stanford University, Stanford, CA 94305, USA.
Journal of Molecular Biology (Impact Factor: 4.33). 02/2011; 409(1):28-35. DOI: 10.1016/j.jmb.2011.02.041
Source: PubMed

ABSTRACT The control circuitry that directs and paces Caulobacter cell cycle progression involves the entire cell operating as an integrated system. This control circuitry monitors the environment and the internal state of the cell, including the cell topology, as it orchestrates orderly activation of cell cycle subsystems and Caulobacter's asymmetric cell division. The proteins of the Caulobacter cell cycle control system and its internal organization are co-conserved across many alphaproteobacteria species, but there are great differences in the regulatory apparatus' functionality and peripheral connectivity to other cellular subsystems from species to species. This pattern is similar to that observed for the "kernels" of the regulatory networks that regulate development of metazoan body plans. The Caulobacter cell cycle control system has been exquisitely optimized as a total system for robust operation in the face of internal stochastic noise and environmental uncertainty. When sufficient details accumulate, as for Caulobacter cell cycle regulation, the system design has been found to be eminently rational and indeed consistent with good design practices for human-designed asynchronous control systems.

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    • "A recent review (McAdams & Shapiro, 2011) describes a fifth (Christen et al., 2011; Tan et al., 2010) regulator, SciP, a CtrA antagonist that inhibits the transcription of at least 58 CtrA-activated genes (Gora et al., 2010; Tan et al., 2010) in swarmer cells, limiting their expression to the predivisional stage of the cell cycle. SciP integrates with the oscillating core cell cycle regulators via CtrA and CcrM (Gora et al., 2010; Tan et al., 2010). "
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    Microbiology 07/2012; 158(Pt 10):2492-503. DOI:10.1099/mic.0.055285-0 · 2.84 Impact Factor
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    • "We have identified the Caulobacter crescentus essential genome to 8 bp resolution by performing ultrahigh-resolution transposon mutagenesis followed by high-throughput DNA sequencing to determine the transposon insertion sites. A notable feature of C. crescentus is that the regulatory events that control polar differentiation and cell-cycle progression are highly integrated, and they occur in a temporally restricted order (McAdams and Shapiro, 2011). Many components of the core regulatory circuit have been identified and simulation of the circuitry has been reported (Shen et al, 2008). "
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