Cell cycle regulation in<i>Caulobacter</i>: location, location, location

Goley, Erin D.; Iniesta, Antonio A.; Shapiro, Lucy

doi:10.1242/jcs.005967

Cited by 55 publications

(48 citation statements)

References 74 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…2A and B). Because the length of the cell cycle varies among growing cells (even within the same agarose-padded slide), it remained unclear if delocalization preceded or followed cytokinesis (i.e., the cytoplasmic compartmentalization of the predivisional cell), a key cell cycle event that determines the fate of daughter cells (2,5,7,16,20,42). Cytokinesis triggers many changes in the cell, including the release of DivK from the new pole into the swarmer cell compartment, while DivK remains localized at the old pole in the stalked cell compartment (27,37).…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Polar Localization of the CckA Histidine Kinase and Cell Cycle Periodicity of the Essential Master Regulator CtrA in Caulobacter crescentus

2010

View full text Add to dashboard Cite

The phosphorylated form of the response regulator CtrA represses DNA replication initiation and regulates the transcription of about 100 cell cycle-regulated genes in Caulobacter crescentus. CtrA activity fluctuates during the cell cycle, and its periodicity is a key element of the engine that drives cell cycle progression. The histidine kinase CckA controls the phosphorylation not only of CtrA but also of CpdR, whose unphosphorylated form promotes CtrA proteolysis. Thus, CckA has a central role in establishing the cell cycle periodicity of CtrA activity by controlling both its phosphorylation and stability. Evidence suggests that the polar localization of CckA during the cell cycle plays a role in CckA function. However, the exact pattern of CckA localization remains controversial. Here, we describe a thorough, quantitative analysis of the spatiotemporal distribution of a functional and chromosomally produced CckA-monomeric green fluorescent protein fusion that affects current models of cell cycle regulation. We also identify two cis-acting regions in CckA that are important for its proper localization and function. The disruption of a PAS-like motif in the sensor domain affects the stability of CckA accumulation at the poles. This is accompanied by a partial loss in CckA function. Shortening an extended linker between ␤-sheets within the CckA catalysis-assisting ATP-binding domain has a more severe effect on CckA polar localization and function. This mutant strain exhibits a dramatic cell-to-cell variability in CpdR levels and CtrA cell cycle periodicity, suggesting that the cell cycle-coordinated polar localization of CckA may be important for the robustness of signal transduction and cell cycle progression.

show abstract

Section: Resultsmentioning

confidence: 99%

“…The alphaproteobacterium Caulobacter crescentus provides a model system that has been particularly useful for unraveling the bacterial cell cycle (2,5,7,16,20,42). Its life cycle is characterized by an asymmetric cell division that yields two distinct daughter cells, the motile swarmer cell and the sessile stalked cell.…”

mentioning

confidence: 99%

Polar Localization of the CckA Histidine Kinase and Cell Cycle Periodicity of the Essential Master Regulator CtrA in Caulobacter crescentus

2010

View full text Add to dashboard Cite

show abstract

“…The transition from transient to permanent attachment has perhaps been best defined for Caulobacter crescentus (13,57,110). In C. crescentus, a complex developmental program is associated with formation of the monolayer.…”

Section: Types Of Adhesive Structures Used To Form the Monolayer Biofilmmentioning

confidence: 99%

Signals, Regulatory Networks, and Materials That Build and Break Bacterial Biofilms

Karatan

Watnick

2009

Microbiol Mol Biol Rev

877

690

View full text Add to dashboard Cite

SUMMARY Biofilms are communities of microorganisms that live attached to surfaces. Biofilm formation has received much attention in the last decade, as it has become clear that virtually all types of bacteria can form biofilms and that this may be the preferred mode of bacterial existence in nature. Our current understanding of biofilm formation is based on numerous studies of myriad bacterial species. Here, we review a portion of this large body of work including the environmental signals and signaling pathways that regulate biofilm formation, the components of the biofilm matrix, and the mechanisms and regulation of biofilm dispersal.

show abstract

“…Bacterial cell polarity underlies a number of critical processes, including the appropriate clustering of chemotactic receptors (12), chromosome segregation (9), and placement of specialized polar structures (6). The bacterial cytoskeleton is an important component of the mechanism underlying the generation of polarity.…”

mentioning

confidence: 99%

Novel Cellular Organization in a Gliding Mycoplasma, Mycoplasma insons

2009

View full text Add to dashboard Cite

Mycoplasmas that are known to exhibit gliding motility possess a differentiated tip structure. This polar organelle mediates cytadherence and gliding motor activity and contains a cytoskeleton-like component that provides structural support. Here, we describe gliding motility and a unique cytoskeleton in Mycoplasma insons, which lacks any obviously differentiated tip structure.Bacterial cell polarity underlies a number of critical processes, including the appropriate clustering of chemotactic receptors (12), chromosome segregation (9), and placement of specialized polar structures (6). The bacterial cytoskeleton is an important component of the mechanism underlying the generation of polarity. The bacterial actin, MreB, is crucial for the morphology of elongated bacterial cells, directing peptidoglycan synthesis along the long axis of the cell (4). In most well-studied bacterial systems, cell shape is dictated by the interaction between the cytoskeleton and the cell wall biosynthetic machinery.In contrast, bacteria of the class Mollicutes lack cell walls. Despite the absence of such a structure, many species maintain cell polarity and distinctive shapes. In Mycoplasma pneumoniae, one cell pole is organized as a terminal organelle. This tip structure, also called the attachment organelle, is readily distinguished from the more pleomorphic cell body by virtue of its slender, elongated appearance and regular dimensions. Adhesins are concentrated at the terminal organelle, which also contains a motor activity for gliding motility (1). Essential for the formation of the M. pneumoniae attachment organelle is a Triton X-100 (TX)-insoluble cytoskeletal structure, the electron-dense core (3), which contains novel proteins found only in M. pneumoniae and its close relatives (2). The distantly related species Mycoplasma mobile has a terminal organelle that also functions in gliding motility, with adhesin and cytoskeleton molecules that are completely unrelated to those of M. pneumoniae present at its cell-proximal end (1, 14). Interestingly, MreB is absent from both species (10, 11). The difference in composition between the terminal organelles of M. pneumoniae and M. mobile suggests that the two have evolved similar structures independently. Thus, mycoplasmas are innovators of cytoskeletons, and the variation among species provides a rich opportunity to learn a great deal about the generation of cell polarity.Many mycoplasmas, including Mycoplasma insons, found in the respiratory tract and blood of healthy green iguanas, lack a distinct tip structure (13). M. insons shares with its two closest relatives, Mycoplasma cavipharyngis and Mycoplasma fastidiosum, a slender rod shape. A series of regularly spaced, electron-dense striations perpendicular to the long axis is visible in thin sections by transmission electron microscopy, and scanning electron microscopy reveals a somewhat twisted appearance along the long axis (13). To understand the underlying cellular organization, we investigated the ultrastructure and behavior of ...

show abstract

Cell cycle regulation inCaulobacter: location, location, location

Cited by 55 publications

References 74 publications

Polar Localization of the CckA Histidine Kinase and Cell Cycle Periodicity of the Essential Master Regulator CtrA in Caulobacter crescentus

Polar Localization of the CckA Histidine Kinase and Cell Cycle Periodicity of the Essential Master Regulator CtrA in Caulobacter crescentus

Signals, Regulatory Networks, and Materials That Build and Break Bacterial Biofilms

Novel Cellular Organization in a Gliding Mycoplasma, Mycoplasma insons

Contact Info

Product

Resources

About