Physical mechanisms of ESCRT-III–driven cell division

Living systems propagate by undergoing rounds of cell growth and division. Cell division is at heart a physical process that requires mechanical forces, usually exerted by assemblies of cytoskeletal polymers. Here we developed a physical model for the ESCRT-III–mediated division of archaeal cells, which despite their structural simplicity share machinery and evolutionary origins with eukaryotes. By comparing the dynamics of simulations with data collected from live cell imaging experiments, we propose that this branch of life uses a previously unidentified division mechanism. Active changes in the curvature of elastic cytoskeletal filaments can lead to filament perversions and supercoiling, to drive ring constriction and deform the overlying membrane. Abscission is then completed following filament disassembly. The model was also used to explore how different adenosine triphosphate (ATP)-driven processes that govern the way the structure of the filament is changed likely impact the robustness and symmetry of the resulting division. Comparisons between midcell constriction dynamics in simulations and experiments reveal a good agreement with the process when changes in curvature are implemented at random positions along the filament, supporting this as a possible mechanism of ESCRT-III–dependent division in this system. Beyond archaea, this study pinpoints a general mechanism of cytokinesis based on dynamic coupling between a coiling filament and the membrane.

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Physical mechanisms of ESCRT-III-driven cell division in archaea

10.1101/2021.03.23.436559 ◽

2021 ◽

Author(s):

L. Harker-Kirschneck ◽

A. E. Hafner ◽

T. Yao ◽

A. Pulschen ◽

F. Hurtig ◽

...

Keyword(s):

Cell Division ◽

Physical Mechanism ◽

Quantitative Comparison ◽

Mechanical Forces ◽

Protein Assemblies ◽

Physical Mechanisms ◽

Evolutionary Origins ◽

Equilibrium Processes ◽

Division Cell ◽

Structural Simplicity

AbstractLiving systems propagate by undergoing rounds of cell growth and division. Cell division is at heart a physical process that requires mechanical forces, usually exerted by protein assemblies. Here we developed the first physical model for the division of archaeal cells, which despite their structural simplicity share machinery and evolutionary origins with eukaryotes. We show how active geometry changes of elastic ESCRT-III filaments, coupled to filament disassembly, are sufficient to efficiently split the cell. We explore how the non-equilibrium processes that govern the filament behaviour impact the resulting cell division. We show how a quantitative comparison between our simulations and dynamic data for ESCRTIII-mediated division in Sulfolobus acidocaldarius, the closest archaeal relative to eukaryotic cells that can currently be cultured in the lab, and reveal the most likely physical mechanism behind its division.

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Faculty Opinions recommendation of Symplastic signaling instructs cell division, cell expansion, and cell polarity in the ground tissue of Arabidopsis thaliana roots.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.726770158.793524851 ◽

2016 ◽

Author(s):

Dolf Weijers ◽

Kuan-Ju Lu

Keyword(s):

Arabidopsis Thaliana ◽

Cell Division ◽

Cell Polarity ◽

Cell Expansion ◽

Ground Tissue ◽

Division Cell

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Cell cycle specific isopentenyl transferase expression led to coordinated enhancement of cell division, cell growth and plant development in transgenic Arabidopsis

Plant Biotechnology ◽

10.5511/plantbiotechnology.22.261 ◽

2005 ◽

Vol 22 (4) ◽

pp. 261-270

Author(s):

Steve S. He ◽

Angel Hoelscher ◽

Jingyue Liu ◽

Dennis O'Neill ◽

Jeanne Layton ◽

...

Keyword(s):

Cell Cycle ◽

Cell Division ◽

Cell Growth ◽

Plant Development ◽

Transgenic Arabidopsis ◽

Isopentenyl Transferase ◽

Division Cell

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Developmental HCN channelopathy results in decreased neural progenitor proliferation and microcephaly in mice

10.1101/2021.04.24.441237 ◽

2021 ◽

Author(s):

Anna Katharina Schlusche ◽

Sabine Ulrike Vay ◽

Niklas Kleinenkuhnen ◽

Steffi Sandke ◽

Rafael Campos-Martin ◽

...

Keyword(s):

Cell Cycle ◽

Cell Division ◽

Membrane Potential ◽

Cell Cycle Progression ◽

Cortical Development ◽

General Mechanism ◽

Hcn Channel ◽

Cycle Progression ◽

Channel Function ◽

Stem And Progenitor Cells

ABSTRACTThe development of the cerebral cortex relies on the controlled division of neural stem and progenitor cells. The requirement for precise spatiotemporal control of proliferation and cell fate places a high demand on the cell division machinery, and defective cell division can cause microcephaly and other brain malformations. Cell-extrinsic and intrinsic factors govern the capacity of cortical progenitors to produce large numbers of neurons and glia within a short developmental time window. In particular, ion channels shape the intrinsic biophysical properties of precursor cells and neurons and control their membrane potential throughout the cell cycle. We found that hyperpolarization-activated cyclic nucleotide-gated cation (HCN)-channel subunits are expressed in mouse, rat, and human neural progenitors. Loss of HCN-channel function in rat neural stem cells impaired their proliferation by affecting the cell-cycle progression, causing G1 accumulation and dysregulation of genes associated with human microcephaly. Transgene-mediated, dominant-negative loss of HCN-channel function in the embryonic mouse telencephalon resulted in pronounced microcephaly. Together, our findings suggest a novel role for HCN-channel subunits as a part of a general mechanism influencing cortical development in mammals.Significance StatementImpaired cell cycle regulation of neural stem and progenitor cells can affect cortical development and cause microcephaly. During cell cycle progression, the cellular membrane potential changes through the activity of ion channels and tends to be more depolarized in proliferating cells. HCN channels, which mediate a depolarizing current in neurons and cardiac cells, are linked to neurodevelopmental diseases, also contribute to the control of cell-cycle progression and proliferation of neuronal precursor cells. In this study, HCN-channel deficiency during embryonic and fetal brain development resulted in marked microcephaly of mice designed to be deficient in HCN-channel function in dorsal forebrain progenitors. The findings suggest that HCN-channel subunits are part of a general mechanism influencing cortical development in mammals.

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Patterns of cell division, cell death and chondrogenesis in cultured aggregates of normal and talpid3 mutant chick limb mesenchyme cells

Development ◽

10.1242/dev.27.1.245 ◽

1972 ◽

Vol 27 (1) ◽

pp. 245-260

Author(s):

D. A. Ede ◽

O. P. Flint

Keyword(s):

Cell Death ◽

Cell Division ◽

Limb Bud ◽

Intercellular Matrix ◽

Blue Stain ◽

Special Pattern ◽

Mesenchyme Cells ◽

Division Cell ◽

Made In

Aggregates were prepared from dissociated mesenchyme cells obtained from normal and talpid mutant chick limb buds at stage 26 and were maintained for 4 days in culture. They were shown by autoradiographic techniques to consist initially of populations of unifoimly dedifferentiated cells within which chondrogenesis was initiated between 1 and 2 days, leading to the formation of areas of precartilage in the interior of the aggregates. Measurements of cell population density, cell death and cell division were made in precartilage and non-cartilage regions on sections prepared from normal and mutant aggregates fixed at 1-day intervals and were related to the pattern of chondrogenesis. Non-cartilage areas consisted of cells surrounding the precartilage areas and extended to the surface of the aggregate; these cells showed no special pattern or histochemical reaction. Precartilage areas consisted of one or more “;condensations”, comprising cells arranged in concentric rings around a central cell or group of cells, characterized by uptake of [35S]sulphate and taking up alcian blue stain in the intercellular matrix. Chondrogenesis was initiated al the condensation foci and spread centrifugally. Condensations were arranged in a simple pattern, roughly equidistantly from each other and never at the surface of the aggregate. The shape and arrangement of the cells comprising them suggested that they were formed by a process of aggregation towards the condensation foci. The relation of these observations to events in the intact limb bud developing in vivo is discussed.

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Anatomy of Wild Garlic Bulbs During and Subsequent to After-Ripening

Weed Science ◽

10.1017/s0043174500035487 ◽

1972 ◽

Vol 20 (3) ◽

pp. 233-237 ◽

Cited By ~ 1

Author(s):

J. F. Stritzke ◽

E. J. Peters

Keyword(s):

Cell Division ◽

Microscopic Examination ◽

Cell Elongation ◽

Leaf Primordia ◽

Root Primordia ◽

Ripening Period ◽

Shoot Primordia ◽

Division Cell ◽

Wild Garlic

Microscopic examination of central and soft offset bulbs of wild garlic(Allium vinealeL.) at senescence of the parent plants in May and June revealed embryonic plants with numerous root primordia and four or five shoot primordia. Hardshell bulbs and aerial bulblets contained only one or two root primordia and three leaf primordia. The embryonic plants of central, soft offset, and hardshell bulbs elongated slowly during the after-ripening period. Rapid cell division, cell elongation, and initiation of new leaves took place after termination of the after-ripening period in all but the dormant hardshell bulbs. In November, new hardshell bulbs could be seen at the base of plants developed from central and soft offset bulbs.

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