PomX, a ParA/MinD ATPase activating protein, is a triple regulator of cell division in Myxococcus xanthus

Cell division site positioning is precisely regulated but the underlying mechanisms are incompletely understood. In the social bacterium Myxococcus xanthus, the ~15 MDa tripartite PomX/Y/Z complex associates with and translocates across the nucleoid in a PomZ ATPase-dependent manner to directly position and stimulate formation of the cytokinetic FtsZ-ring at midcell, and then undergoes fission during division. Here, we demonstrate that PomX consists of two functionally distinct domains and has three functions. The N-terminal domain stimulates ATPase activity of the ParA/MinD ATPase PomZ. The C-terminal domain interacts with PomY and forms polymers, which serve as a scaffold for PomX/Y/Z complex formation. Moreover, the PomX/PomZ interaction is important for fission of the PomX/Y/Z complex. These observations together with previous work support that the architecturally diverse ATPase activating proteins of ParA/MinD ATPases are highly modular and use the same mechanism to activate their cognate ATPase via a short positively charged N-terminal extension.

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PomX, a ParA/MinD ATPase activating protein, is a triple regulator of cell division in Myxococcus xanthus

10.1101/2020.12.14.422651 ◽

2020 ◽

Author(s):

Dominik Schumacher ◽

Andrea Harms ◽

Silke Bergeler ◽

Erwin Frey ◽

Lotte Søgaard-Andersen

Keyword(s):

Cell Division ◽

Myxococcus Xanthus ◽

Dependent Manner ◽

Ftsz Ring ◽

Daughter Cells ◽

Terminal Domain ◽

Division Site ◽

The Social ◽

Interaction Interaction ◽

Positively Charged

SummaryCell division is precisely regulated to generate daughter cells of correct size and shape. In the social bacterium Myxococcus xanthus, the tripartite PomX/Y/Z complex directly stimulates positioning of the cytokinetic FtsZ-ring at midcell to mark the division site. The ∼15 MDa PomX/Y/Z complex associates with the nucleoid in a PomZ-dependent manner, translocates to midcell to stimulate FtsZ-ring formation, and undergoes fission during division. We demonstrate that PomX consists of two functionally distinct domains and has three functions. The N-terminal domain interacts with the ParA/MinD ATPase PomZ and stimulates PomZ ATPase activity. The C-terminal domain mediates PomX self-interaction, interaction to PomY, and serves as a scaffold for PomX/Y/Z complex formation. Moreover, the PomX/PomZ interaction is important for fission. These observations together with previous work support that the architecturally diverse ATPase activating proteins of ParA/MinD ATPases are highly modular and use the same mechanism to activate their cognate ATPase via a short positively charged N-terminal extension.

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Characterization of YmgF, a 72-Residue Inner Membrane Protein That Associates with the Escherichia coli Cell Division Machinery

Journal of Bacteriology ◽

10.1128/jb.00331-08 ◽

2008 ◽

Vol 191 (1) ◽

pp. 333-346 ◽

Cited By ~ 44

Author(s):

Gouzel Karimova ◽

Carine Robichon ◽

Daniel Ladant

Keyword(s):

Escherichia Coli ◽

Cell Division ◽

Membrane Protein ◽

Integral Membrane Protein ◽

Dependent Manner ◽

E Coli ◽

Division Site ◽

Inner Membrane Protein ◽

Two Hybrid

ABSTRACT Formation of the Escherichia coli division septum is catalyzed by a number of essential proteins (named Fts) that assemble into a ring-like structure at the future division site. Many of these Fts proteins are intrinsic transmembrane proteins whose functions are largely unknown. In the present study, we attempted to identify a novel putative component(s) of the E. coli cell division machinery by searching for proteins that could interact with known Fts proteins. To do that, we used a bacterial two-hybrid system based on interaction-mediated reconstitution of a cyclic AMP (cAMP) signaling cascade to perform a library screening in order to find putative partners of E. coli cell division protein FtsL. Here we report the characterization of YmgF, a 72-residue integral membrane protein of unknown function that was found to associate with many E. coli cell division proteins and to localize to the E. coli division septum in an FtsZ-, FtsA-, FtsQ-, and FtsN-dependent manner. Although YmgF was previously shown to be not essential for cell viability, we found that when overexpressed, YmgF was able to overcome the thermosensitive phenotype of the ftsQ1(Ts) mutation and restore its viability under low-osmolarity conditions. Our results suggest that YmgF might be a novel component of the E. coli cell division machinery.

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TTK/hMps1 Mediates the p53-Dependent Postmitotic Checkpoint by Phosphorylating p53 at Thr18

Molecular and Cellular Biology ◽

10.1128/mcb.01837-08 ◽

2009 ◽

Vol 29 (11) ◽

pp. 2935-2944 ◽

Cited By ~ 40

Author(s):

Yi-Fu Huang ◽

Margaret Dah-Tsyr Chang ◽

Sheau-Yann Shieh

Keyword(s):

Cell Division ◽

Genome Stability ◽

Spindle Checkpoint ◽

Underlying Mechanism ◽

Dependent Manner ◽

Deficient Mutant ◽

Present Evidence ◽

Checkpoint Kinase ◽

Terminal Domain

ABSTRACT Upon prolonged arrest in mitosis, cells undergo adaptation and exit mitosis without cell division. These tetraploid cells are either eliminated by apoptosis or arrested in the subsequent G1 phase in a spindle checkpoint- and p53-dependent manner. p53 has long been known to be activated by spindle poisons, such as nocodazole and Taxol, although the underlying mechanism remains elusive. Here we present evidence that stabilization and activation of p53 by spindle disruption requires the spindle checkpoint kinase TTK/hMps1. TTK/hMps1 phoshorylates the N-terminal domain of p53 at Thr18, and this phosphorylation disrupts the interaction with MDM2 and abrogates MDM2-mediated p53 ubiquitination. Phosphorylation at Thr18 enhances p53-dependent activation of not only p21 but also Lats2, two mediators of the postmitotic checkpoint. Furthermore, a phospho-mimicking substitution at Thr18 (T18D) is more competent than the phospho-deficient mutant (T18A) in rescuing the tetraploid checkpoint defect of p53-depleted cells. Our findings therefore provide a mechanism connecting the spindle checkpoint with p53 in the maintenance of genome stability.

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Tumor suppressor APC is an attenuator of spindle-pulling forces during C. elegans asymmetric cell division

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1712052115 ◽

2018 ◽

Vol 115 (5) ◽

pp. E954-E963 ◽

Cited By ~ 9

Author(s):

Kenji Sugioka ◽

Lars-Eric Fielmich ◽

Kota Mizumoto ◽

Bruce Bowerman ◽

Sander van den Heuvel ◽

...

Keyword(s):

Cell Division ◽

Tumor Suppressor ◽

Mitotic Spindle ◽

Asymmetric Cell Division ◽

Cell Cortex ◽

Dependent Manner ◽

C Elegans ◽

Pulling Forces ◽

Underlying Mechanisms ◽

Pulling Force

The adenomatous polyposis coli (APC) tumor suppressor has dual functions in Wnt/β-catenin signaling and accurate chromosome segregation and is frequently mutated in colorectal cancers. Although APC contributes to proper cell division, the underlying mechanisms remain poorly understood. Here we show that Caenorhabditis elegans APR-1/APC is an attenuator of the pulling forces acting on the mitotic spindle. During asymmetric cell division of the C. elegans zygote, a LIN-5/NuMA protein complex localizes dynein to the cell cortex to generate pulling forces on astral microtubules that position the mitotic spindle. We found that APR-1 localizes to the anterior cell cortex in a Par–aPKC polarity-dependent manner and suppresses anterior centrosome movements. Our combined cell biological and mathematical analyses support the conclusion that cortical APR-1 reduces force generation by stabilizing microtubule plus-ends at the cell cortex. Furthermore, APR-1 functions in coordination with LIN-5 phosphorylation to attenuate spindle-pulling forces. Our results document a physical basis for the attenuation of spindle-pulling force, which may be generally used in asymmetric cell division and, when disrupted, potentially contributes to division defects in cancer.

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Growth Rate-Dependent Regulation of Medial FtsZ Ring Formation

Journal of Bacteriology ◽

10.1128/jb.185.9.2826-2834.2003 ◽

2003 ◽

Vol 185 (9) ◽

pp. 2826-2834 ◽

Cited By ~ 109

Author(s):

Richard B. Weart ◽

Petra Anne Levin

Keyword(s):

Cell Cycle ◽

Growth Rate ◽

Transcriptional Control ◽

Doubling Time ◽

Ring Formation ◽

Intracellular Concentration ◽

Dependent Manner ◽

Ftsz Ring ◽

Division Site ◽

Rate Dependent

ABSTRACT FtsZ is an essential cell division protein conserved throughout the bacteria and archaea. In response to an unknown cell cycle signal, FtsZ polymerizes into a ring that establishes the future division site. We conducted a series of experiments examining the link between growth rate, medial FtsZ ring formation, and the intracellular concentration of FtsZ in the gram-positive bacterium Bacillus subtilis. We found that, although the frequency of cells with FtsZ rings varies as much as threefold in a growth rate-dependent manner, the average intracellular concentration of FtsZ remains constant irrespective of doubling time. Additionally, expressing ftsZ solely from a constitutive promoter, thereby eliminating normal transcriptional control, did not alter the growth rate regulation of medial FtsZ ring formation. Finally, our data indicate that overexpressing FtsZ does not dramatically increase the frequency of cells with medial FtsZ rings, suggesting that the mechanisms governing ring formation are refractile to increases in FtsZ concentration. These results support a model in which the timing of FtsZ assembly is governed primarily through cell cycle-dependent changes in FtsZ polymerization kinetics and not simply via oscillations in the intracellular concentration of FtsZ. Importantly, this model can be extended to the gram-negative bacterium Escherichia coli. Our data show that, like those in B. subtilis, average FtsZ levels in E. coli are constant irrespective of doubling time.

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The Division Inhibitor EzrA Contains a Seven-Residue Patch Required for Maintaining the Dynamic Nature of the Medial FtsZ Ring

Journal of Bacteriology ◽

10.1128/jb.01172-07 ◽

2007 ◽

Vol 189 (24) ◽

pp. 9001-9010 ◽

Cited By ~ 30

Author(s):

Daniel P. Haeusser ◽

Anna Cristina Garza ◽

Amy Z. Buscher ◽

Petra Anne Levin

Keyword(s):

De Novo ◽

Dependent Manner ◽

Dynamic Nature ◽

Ftsz Ring ◽

Division Site ◽

C Terminus ◽

Ftsz Assembly ◽

Mutant Cells ◽

Precise Role

ABSTRACT The essential cytoskeletal protein FtsZ assembles into a ring-like structure at the nascent division site and serves as a scaffold for the assembly of the prokaryotic division machinery. We previously characterized EzrA as an inhibitor of FtsZ assembly in Bacillus subtilis. EzrA interacts directly with FtsZ to prevent aberrant FtsZ assembly and cytokinesis at cell poles. EzrA also concentrates at the cytokinetic ring in an FtsZ-dependent manner, although its precise role at this position is not known. Here, we identified a conserved patch of amino acids in the EzrA C terminus that is essential for localization to the FtsZ ring. Mutations in this patch (designated the “QNR patch”) abolish EzrA localization to midcell but do not significantly affect EzrA's ability to inhibit FtsZ assembly at cell poles. ezrA QNR patch mutant cells exhibit stabilized FtsZ assembly at midcell and are significantly longer than wild-type cells, despite lacking extra FtsZ rings. These results indicate that EzrA has two distinct activities in vivo: (i) preventing aberrant FtsZ ring formation at cell poles through inhibition of de novo FtsZ assembly and (ii) maintaining proper FtsZ assembly dynamics within the medial FtsZ ring, thereby rendering it sensitive to the factors responsible for coordinating cell growth and cell division.

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ZapE Is a Novel Cell Division Protein Interacting with FtsZ and Modulating the Z-Ring Dynamics

mBio ◽

10.1128/mbio.00022-14 ◽

2014 ◽

Vol 5 (2) ◽

Cited By ~ 23

Author(s):

Benoit S. Marteyn ◽

Gouzel Karimova ◽

Andrew K. Fenton ◽

Anastasia D. Gazi ◽

Nicholas West ◽

...

Keyword(s):

Cell Division ◽

Bacterial Cell ◽

Dependent Manner ◽

Bacterial Cell Division ◽

Low Oxygen ◽

Ftsz Ring ◽

Division Process ◽

Z Ring ◽

Cell Division Protein

ABSTRACTBacterial cell division requires the formation of a mature divisome complex positioned at the midcell. The localization of the divisome complex is determined by the correct positioning, assembly, and constriction of the FtsZ ring (Z-ring). Z-ring constriction control remains poorly understood and (to some extent) controversial, probably due to the fact that this phenomenon is transient and controlled by numerous factors. Here, we characterize ZapE, a novel ATPase found in Gram-negative bacteria, which is required for growth under conditions of low oxygen, while loss ofzapEresults in temperature-dependent elongation of cell shape. We found that ZapE is recruited to the Z-ring during late stages of the cell division process and correlates with constriction of the Z-ring. Overexpression or inactivation ofzapEleads to elongation ofEscherichia coliand affects the dynamics of the Z-ring during division.In vitro, ZapE destabilizes FtsZ polymers in an ATP-dependent manner.IMPORTANCEBacterial cell division has mainly been characterizedin vitro. In this report, we could identify ZapE as a novel cell division protein which is not essentialin vitrobut is required during an infectious process. The bacterial cell division process relies on the assembly, positioning, and constriction of FtsZ ring (the so-called Z-ring). Among nonessential cell division proteins recently identified, ZapE is the first in which detection at the Z-ring correlates with its constriction. We demonstrate that ZapE abundance has to be tightly regulated to allow cell division to occur; absence or overexpression of ZapE leads to bacterial filamentation. AszapEis not essential, we speculate that additional Z-ring destabilizing proteins transiently recruited during late cell division process might be identified in the future.

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Bacillus subtilis EzrA and FtsL synergistically regulate FtsZ ring dynamics during cell division

Microbiology ◽

10.1099/mic.0.28497-0 ◽

2006 ◽

Vol 152 (4) ◽

pp. 1129-1141 ◽

Cited By ~ 32

Author(s):

Yoshikazu Kawai ◽

Naotake Ogasawara

Keyword(s):

Bacillus Subtilis ◽

Cell Division ◽

Synthetic Lethality ◽

Lower Amount ◽

Wild Type ◽

Ftsz Ring ◽

Division Site ◽

Ring Assembly ◽

Ring Constriction

Previous work has shown that the Bacillus subtilis EzrA protein directly inhibits FtsZ ring assembly, which is required for normal cell division, and that loss of EzrA results in hyperstabilization of the FtsZ polymer in vivo. Here, it was found that in ezrA-disrupted cells, artificial expression of YneA, which suppresses cell division during the SOS response, and disruption of noc (yyaA), which acts as an effector of nucleoid occlusion, resulted in accumulation of multiple non-constricting FtsZ rings, inhibition of cell division, and synthetic lethality. Overexpression of the essential cell division protein FtsL suppressed the effect of ezrA disruption. FtsL overexpression recovered the delayed FtsZ ring constriction seen in ezrA-disrupted wild-type cells. Conversely, the absence of EzrA caused lethality in cells producing a lower amount of FtsL than wild-type cells. It has previously been reported that FtsL is recruited to the division site during the later stages of cell division, although its exact role is currently unknown. The results of this study suggest that FtsL and EzrA synergistically regulate the FtsZ ring constriction in B. subtilis. Interestingly, FtsL overexpression also suppressed the cell division inhibition due to YneA expression or Noc inactivation in ezrA-disrupted cells.

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MinC N- and C-Domain Interactions Modulate FtsZ Assembly, Division Site Selection, and MinD-Dependent Oscillation inEscherichia coli

Journal of Bacteriology ◽

10.1128/jb.00374-18 ◽

2018 ◽

Vol 201 (4) ◽

Cited By ~ 5

Author(s):

Christopher J. LaBreck ◽

Joseph Conti ◽

Marissa G. Viola ◽

Jodi L. Camberg

Keyword(s):

Escherichia Coli ◽

Cell Division ◽

Site Selection ◽

Fluorescent Protein ◽

Site Mutation ◽

Content Type ◽

Ftsz Ring ◽

Division Site ◽

Z Ring

ABSTRACTThe Min system inEscherichia coli, consisting of MinC, MinD, and MinE proteins, regulates division site selection by preventing assembly of the FtsZ-ring (Z-ring) and exhibits polar oscillationin vivo. MinC antagonizes FtsZ polymerization, andin vivo, the cellular location of MinC is controlled by a direct association with MinD at the membrane. To further understand the interactions of MinC with FtsZ and MinD, we performed a mutagenesis screen to identify substitutions inminCthat are associated with defects in cell division. We identified amino acids in both the N- and C-domains of MinC that are important for direct interactions with FtsZ and MinDin vitro, as well as mutations that modify the observedin vivooscillation of green fluorescent protein (GFP)-MinC. Our results indicate that there are two distinct surface-exposed sites on MinC that are important for direct interactions with FtsZ, one at a cleft on the surface of the N-domain and a second on the C-domain that is adjacent to the MinD interaction site. Mutation of either of these sites leads to slower oscillation of GFP-MinCin vivo, although the MinC mutant proteins are still capable of a direct interaction with MinD in phospholipid recruitment assays. Furthermore, we demonstrate that interactions between FtsZ and both sites of MinC identified here are important for assembly of FtsZ-MinC-MinD complexes and that the conserved C-terminal end of FtsZ is not required for MinC-MinD complex formation with GTP-dependent FtsZ polymers.IMPORTANCEBacterial cell division proceeds through the coordinated assembly of the FtsZ-ring, or Z-ring, at the site of division. Assembly of the Z-ring requires polymerization of FtsZ, which is regulated by several proteins in the cell. InEscherichia coli, the Min system, which contains MinC, MinD, and MinE proteins, exhibits polar oscillation and inhibits the assembly of FtsZ at nonseptal locations. Here, we identify regions on the surface of MinC that are important for contacting FtsZ and destabilizing FtsZ polymers.

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Progression of the late-stage divisome is unaffected by the depletion of the cytoplasmic FtsZ pool

Communications Biology ◽

10.1038/s42003-021-01789-9 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Nadine Silber ◽

Christian Mayer ◽

Cruz L. Matos de Opitz ◽

Peter Sass

Keyword(s):

Bacillus Subtilis ◽

Cell Division ◽

Late Stage ◽

Essential Role ◽

Ftsz Ring ◽

Division Site ◽

Ring Dynamics ◽

Cell Division Protein ◽

Late Stages

AbstractCell division is a central and essential process in most bacteria, and also due to its complexity and highly coordinated nature, it has emerged as a promising new antibiotic target pathway in recent years. We have previously shown that ADEP antibiotics preferably induce the degradation of the major cell division protein FtsZ, thereby primarily leading to a depletion of the cytoplasmic FtsZ pool that is needed for treadmilling FtsZ rings. To further investigate the physiological consequences of ADEP treatment, we here studied the effect of ADEP on the different stages of the FtsZ ring in rod-shaped bacteria. Our data reveal the disintegration of early FtsZ rings during ADEP treatment in Bacillus subtilis, indicating an essential role of the cytoplasmic FtsZ pool and thus FtsZ ring dynamics during initiation and maturation of the divisome. However, progressed FtsZ rings finalized cytokinesis once the septal peptidoglycan synthase PBP2b, a late-stage cell division protein, colocalized at the division site, thus implying that the concentration of the cytoplasmic FtsZ pool and FtsZ ring dynamics are less critical during the late stages of divisome assembly and progression.

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