Mystery at the heart of life

_{Denyse O'Leary

December 21, 2014

Cell biology, Intelligent Design, News}

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By Biologic Institute’s Ann Gauger, at Christianity Today’s Behemoth, the secret life of cells:

Our bodies are made up of some 100 trillion cells. We tend to think of cells as static, because that’s how they were presented to us in textbooks. In fact, the cell is like the most antic, madcap, crowded (yet fantastically efficient) city you can picture. And at its heart lies a mystery—or I should say, several mysteries—involving three special kinds of molecules: DNA, RNA, and proteins.

These molecules are assembled into long chains called polymers, and are uniquely suited for the roles they play. More importantly, life absolutely depends upon them. We have to have DNA, RNA, and protein all present and active at the same time for a living organism to live.

How they work together so optimally and efficiently is not merely amazing, but also a great enigma, a mystery that lies at the heart of life itself. More. Paywall soon after. May be worth it.

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Comments

As several major BRAIN initiatives are just now getting under way, perhaps this is the right time to ponder the question: Imagine if all the molecular and cellular parts were made available, what is the basic design principle that evolution and development should employ in constructing brains? [...] one can at least take a page from what architects or product-design engineers have routinely done - ask what the basic function of the structure or product is, then try to come up with the corresponding design blueprint to achieve it.
A postulate on the brain’s basic wiring logic Joe Z Tsien Trends Neurosci. 38(11): 669–671. doi: 10.1016/j.tins.2015.09.002

Did somebody say 'design'? :) Complex complexity.Dionisio_{May 28, 2017
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Alzheimer's disease (AD) is the most common age-related dementia. Pathognomonic accumulation of cerebral ?-amyloid plaques likely results from imbalanced production and removal of amyloid-? (A?) peptides. In AD, innate immune cells lose their ability to restrict cerebral A? accumulation. At least in principle, mononuclear phagocytes can be enlisted to clear A?/?-amyloid from the brain. While the classical focus has been on dampening neuroinflammation in the context of AD, we hypothesize that rebalancing cerebral innate immunity by inhibiting actions of key anti-inflammatory cytokines returns the brain to a physiological state. Recent experiments demonstrating beneficial effects of blocking anti-inflammatory cytokine signaling in preclinical mouse models provide supportive evidence. This concept represents an important step toward innate immune-targeted therapy to combat AD.
Innate Immunity Fights Alzheimer's Disease Marie-Victoire Guillot-Sestier, Kevin R. Doty, Terrence Town https://doi.org/10.1016/j.tins.2015.08.008 Trends in Neuroscience - Cell Press Volume 38, Issue 11, Pages 674–681

Had we stayed in Eden, none of this would have been an issue. We made the wrong choice. Too late now. Complex complexity.Dionisio_{May 27, 2017
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Some problems in neuroscience are nearly solved. For others, solutions are decades away. The current pace of advances in methods forces us to take stock, to ask where we are going, and what we should research next.
The unsolved problems of neuroscience Ralph Adolphs https://doi.org/10.1016/j.tics.2015.01.007 Trends in Cognitive Sciences Volume 19, Issue 4, Pages 173-175

Complex complexity.Dionisio_{May 26, 2017
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There is currently no molecular explanation for how differences in sibling cell size could affect cell fate [...] Whether animal cells produce sibling cells that are equal or unequal in size seems to be tightly controlled during development. It is currently not clear how Klp10A regulates the size of centrosomes, or what molecular mechanisms regulate spindle asymmetry in germline stem cells and other systems. In the future it may be possible to develop tools that allow us to artificially change the relative sizes of sibling cells in order to investigate how this affects animal development.
Cell division: Sibling cell size matters Clemens Cabernard DOI: http://dx.doi.org/10.7554/eLife.24038 eLife 2017;6:e24038

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Cell division is a highly regulated and tightly choreographed process. It ensures that the DNA, organelles and other components in a cell are correctly distributed between the two "sibling" cells that are produced during the cell division process. A motor protein called Klp10A ensures that germline stem cells in male fruit flies divide to produce two sibling cells that are equal in size.
Cell division: Sibling cell size matters Clemens Cabernard DOI: http://dx.doi.org/10.7554/eLife.24038 eLife 2017;6:e24038

Did somebody say "tightly choreographed process"? Whose choreography? Complex complexity.Dionisio_{May 23, 2017
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Gametes are generated through a specialized cell division called meiosis, in which ploidy is reduced by half because two consecutive rounds of chromosome segregation, meiosis I and meiosis II, occur without intervening DNA replication. Cdc14 also regulates the meiosis I to meiosis II transition, though its mode of action has remained unclear. Unique, yet poorly understood, controls allow a second round of spindle formation, but prevent a second round of DNA replication. Cdc14 is required to re-license SPB duplication between meiosis I and meiosis II and that its retention in the nucleolus during early meiosis is required to allow SPB separation during meiosis I. The significance of the asymmetric localization of Cdc14 at the SPB during anaphase I therefore remains unexplained. Understanding how this is regulated to ensure step-by-step release of cohesion, spindle elongation and spindle disassembly at meiosis I is an important priority for the future.
Cdc14 phosphatase directs centrosome re-duplication at the meiosis I to meiosis II transition in budding yeast Colette Fox, Juan Zou, Juri Rappsilber and Adele L. Marston Wellcome Open Res. 2: 2. doi: 10.12688/wellcomeopenres.10507.1

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1 Modeling Asymmetric Cell Division in Caulobacter crescentus Using a Boolean Logic Approach . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Ismael Sanchez-Osorio, Carlos A. Hernandez-Mart?nez, and Agustino Mart?nez-Antonio 2 Spatiotemporal Models of the Asymmetric Division Cycle of Caulobacter crescentus . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Kartik Subramanian and John J. Tyson 3 Intrinsic and Extrinsic Determinants Linking Spindle Pole Fate, Spindle Polarity, and Asymmetric Cell Division in the Budding Yeast S. cerevisiae . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 Marco Geymonat and Marisa Segal 4 Wnt Signaling Polarizes C. elegans Asymmetric Cell Divisions During Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 Arielle Koonyee Lam and Bryan T. Phillips 5 Asymmetric Cell Division in the One-Cell C. elegans Embryo: Multiple Steps to Generate Cell Size Asymmetry . . . . . . . . . . . . . . 115 Anne Pacquelet 6 Size Matters: How C. elegans Asymmetric Divisions Regulate Apoptosis . . . . . . . . . . . . . . . . . . . . . . . . . . 141 Jerome Teuliere and Gian Garriga 7 The Midbody and its Remnant in Cell Polarization and Asymmetric Cell Division . . . . . . . . . . . . . . . . . . . . . . . . . . 165 Christian Pohl 8 Drosophila melanogaster Neuroblasts: A Model for Asymmetric Stem Cell Divisions . . . . . . . . . . . . . . . . . . . . . . . . 183 Emmanuel Gallaud, Tri Pham, and Clemens Cabernard 9 Asymmetric Divisions in Oogenesis . . . . . . . . . . . . . . . . . . . . . . . . . 211 Szczepan M. Bilinski, Jacek Z. Kubiak, and Malgorzata Kloc 10 Asymmetric Localization and Distribution of Factors Determining Cell Fate During Early Development of Xenopus laevis . . . . . . . . . 229 Radek Sindelka, Monika Sidova, Pavel Abaffy, and Mikael Kubista 11 Asymmetries in Cell Division, Cell Size, and Furrowing in the Xenopus laevis Embryo . . . . . . . . . . . . . . . . . . . . . . . . . . 243 Jean-Pierre Tassan, Martin Wühr, Guillaume Hatte, and Jacek Kubiak 12 Asymmetric and Unequal Cell Divisions in Ascidian Embryos . . . . 261 Takefumi Negishi and Hiroki Nishida 13 Asymmetries and Symmetries in the Mouse Oocyte and Zygote . . . 285 Agathe Chaigne, Marie-Emilie Terret, and Marie-Helene Verlhac 14 Symmetry Does not Come for Free: Cellular Mechanisms to Achieve a Symmetric Cell Division . . . . . . . . . . . . . . . . . . . . . . . 301 Damian Dudka and Patrick Meraldi 15 A Comparative Perspective on Wnt/?-Catenin Signalling in Cell Fate Determination . . . . . . . . . . . . . . . . . . . . . . . . . . . 323 Clare L. Garcin and Shukry J. Habib 16 Extracellular Regulation of the Mitotic Spindle and Fate Determinants Driving Asymmetric Cell Division . . . . . . . . . . . . . . 351 Prestina Smith, Mark Azzam, and Lindsay Hinck 17 Regulation of Asymmetric Cell Division in Mammalian Neural Stem and Cancer Precursor Cells . . . . . . . . . . . . . . . . . . . . . . . . . . 375 Mathieu Daynac and Claudia K. Petritsch 18 Molecular Programs Underlying Asymmetric Stem Cell Division and Their Disruption in Malignancy . . . . . . . . . . . . . . . . . . . . . . . . 401 Subhas Mukherjee and Daniel J. Brat
Asymmetric Cell Division in Development, Differentiation and Cancer Editors: Jean-Pierre Tassan, Jacek Z. Kubiak ISBN: 978-3-319-53149-6 (Print) 978-3-319-53150-2 Book Results and Problems in Cell Differentiation Volume 61 2017

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[...] there is a need for a machinery that assures the delivery of genetic material into the elongating cell [...] [...] the mechanism of the movement of chromosomes remains unknown.
Unique Function of the Bacterial Chromosome Segregation Machinery in Apically Growing Streptomyces - Targeting the Chromosome to New Hyphal Tubes and its Anchorage at the Tips Agnieszka Kois-Ostrowska, Agnieszka Strzalka, Natalia Lipietta, Emma Tilley, Jolanta Zakrzewska-Czerwi?ska, Paul Herron, Dagmara Jakimowicz PLoS Genet 12(12):e1006488. doi:10.1371/journal.pgen.1006488

Did somebody say "there is a need"? Whose "need"? Complex complexity.Dionisio_{May 23, 2017
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@3427-3430 adjust the citation:

Unique Function of the Bacterial Chromosome Segregation Machinery in Apically Growing Streptomyces - Targeting the Chromosome to New Hyphal Tubes and its Anchorage at the Tips Agnieszka Kois-Ostrowska, Agnieszka Strzalka, Natalia Lipietta, Emma Tilley, Jolanta Zakrzewska-Czerwi?ska, Paul Herron, Dagmara Jakimowicz PLoS Genet 12(12):e1006488. doi:10.1371/journal.pgen.1006488

Dionisio_{May 23, 2017
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It is tempting to speculate that the role of ParB complexes at the chromosomes along the hyphae is to facilitate targeting of chromosomes to the newly forming branches by interacting with ParA. This would represent a new function of ParA and polarisome complexes during germination and formation of new branches.
Unique Function of the Bacterial Chromosome Segregation Machinery in Apically Growing Streptomyces - Targeting the Chromosome to New Hyphal Tubes and its Anchorage at the Tips Agnieszka Kois-Ostrowska, Agnieszka Strzalka, Natalia Lipietta, Emma Tilley, Jolanta Zakrzewska-Czerwi?ska, Paul Herron, Dagmara Jakimowicz PLoS Genet 12(12):e1006488. doi:10.1371/journal.pgen.1006488

Did somebody say "tempting to speculate" ? That seems like an honest statement. Complex complexity.Dionisio_{May 23, 2017
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Until now, it was believed that the function of the polar complex was to maintain the rigidity of the extending tip and to establish the cell wall synthesis machinery [...] We have revealed an additional function, which is to provide anchorage for the oriC of the apical chromosome.
Unique Function of the Bacterial Chromosome Segregation Machinery in Apically Growing Streptomyces - Targeting the Chromosome to New Hyphal Tubes and its Anchorage at the Tips Agnieszka Kois-Ostrowska, Agnieszka Strzalka, Natalia Lipietta, Emma Tilley, Jolanta Zakrzewska-Czerwi?ska, Paul Herron, Dagmara Jakimowicz

Did somebody say "it was believed"? Belief-based science? Shouldn't it be evidence-based instead? Did somebody say "additional function"? Complex complexity.Dionisio_{May 23, 2017
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[...] in vegetative hyphae every copy of the chromosome is complexed with ParB, whereas ParA, through interaction with the apical protein complex (polarisome), tightly anchors only one chromosome at the hyphal tip. The anchor is maintained during replication, when ParA captures one of the daughter oriCs. During spore germination and branching, ParA targets one of the multiple chromosomal copies to the new hyphal tip, enabling efficient elongation of hyphal tube. [...] our studies reveal a novel role for ParAB proteins during hyphal tip establishment and extension.
Unique Function of the Bacterial Chromosome Segregation Machinery in Apically Growing Streptomyces - Targeting the Chromosome to New Hyphal Tubes and its Anchorage at the Tips Agnieszka Kois-Ostrowska, Agnieszka Strzalka, Natalia Lipietta, Emma Tilley, Jolanta Zakrzewska-Czerwi?ska, Paul Herron, Dagmara Jakimowicz

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[...] the requirement for active chromosome segregation is unclear in the absence of canonical cell division during vegetative growth except in the process of branch formation. The mechanism by which chromosomes are targeted to new hyphae in streptomycete vegetative growth has remained unknown until now.
Unique Function of the Bacterial Chromosome Segregation Machinery in Apically Growing Streptomyces - Targeting the Chromosome to New Hyphal Tubes and its Anchorage at the Tips Agnieszka Kois-Ostrowska, Agnieszka Strzalka, Natalia Lipietta, Emma Tilley, Jolanta Zakrzewska-Czerwi?ska, Paul Herron, Dagmara Jakimowicz

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The coordination of chromosome segregation with cell growth is fundamental to the proliferation of any organism. In most unicellular bacteria, chromosome segregation is strictly coordinated with cell division and involves ParA that moves the ParB nucleoprotein complexes bi- or unidirectionally toward the cell pole(s). However, the chromosome organization in multiploid, apically extending and branching Streptomyces hyphae challenges the known mechanisms of bacterial chromosome segregation.
Unique Function of the Bacterial Chromosome Segregation Machinery in Apically Growing Streptomyces - Targeting the Chromosome to New Hyphal Tubes and its Anchorage at the Tips Agnieszka Kois-Ostrowska, Agnieszka Strzalka, Natalia Lipietta, Emma Tilley, Jolanta Zakrzewska-Czerwi?ska, Paul Herron, Dagmara Jakimowicz

Did somebody say "strictly coordinated"? Complex complexity.Dionisio_{May 23, 2017
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[...] Spo0M interacts with a molecular complex of proteins involved in cell division. There are still several open questions related to the functions of Spo0M in B. subtilis [...] [...] Spo0M is not only a regulator of sporulation but also plays an important role during the vegetative growth of the bacterium. An improved understanding of the multifunctional role of Spo0M will allow a better understanding of the different cell processes in which Spo0M participate and how this processes are related.
Analysis of Spo0M function in Bacillus subtilis Luz Adriana Vega-Cabrera1, Adan Guerrero2, Jose Luis Rodriguez-Mejia, Maria Luisa Tabche, Christopher D. Wood, Rosa-Maria Gutierrez-Rios, Enrique Merino, Liliana Pardo-Lopez DOI: 10.1371/journal.pone.0172737 PLoS ONE 12(2):e0172737

Work in progress... stay tuned. Complex complexity.Dionisio_{May 23, 2017
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Spo0M has been previously reported as a regulator of sporulation in Bacillus subtilis; however, little is known about the mechanisms through which it participates in sporulation, and there is no information to date that relates this protein to other processes in the bacterium. [...] Spo0M function is not necessarily restricted to sporulation [...] [...] Spo0M interacts with cytoskeletal proteins involved in cell division [...] Spo0M expression is not restricted to the transition phase or sporulation; rather, its expression begins during the early stages of growth and Spo0M localization in B. subtilis depends on the bacterial life cycle and could be related to an additional proposed function. Our work paves the way for re-evaluation of the role of Spo0M in bacterial cell.
Analysis of Spo0M function in Bacillus subtilis Luz Adriana Vega-Cabrera1, Adan Guerrero2, Jose Luis Rodriguez-Mejia, Maria Luisa Tabche, Christopher D. Wood, Rosa-Maria Gutierrez-Rios, Enrique Merino, Liliana Pardo-Lopez DOI: 10.1371/journal.pone.0172737 PLoS ONE 12(2):e0172737

Did somebody say "re-evaluation of the role"? Complex complexity.Dionisio_{May 23, 2017
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The gram-negative bacterium Caulobacter crescentus is a powerful model organism for studies of bacterial cell cycle regulation. Although the major regulators and their connections in Caulobacter have been identified, it still is a challenge to properly understand the dynamics of its circuitry which accounts for both cell cycle progression and arrest. [...] the key decision module in Caulobacter is built from a limit cycle oscillator which controls the DNA replication program. The effect of an induced cell cycle arrest is demonstrated to be a key feature to classify the underlying dynamics.
Core-oscillator model of Caulobacter crescentus Yves Vandecan, Emanuele Biondi, and Ralf Blossey Phys. Rev. E 93, 062413 DOI: 10.1103/PhysRevE.93.062413

Complex complexity.Dionisio_{May 22, 2017
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On the one hand, what we currently know about the regulatory network that controls the cell cycle in C. crescentus is the fact that it directs a robust and complex process, able to buffer perturbations on the network without propagating dysfunction. On the other hand, the relatively long cascade of kinases and proteolytic proteins makes the network sensitive enough to respond to multiple environmental conditions.
Dynamical Modeling of the Cell Cycle and Cell Fate Emergence in Caulobacter crescentus César Quiñones-Valles, Ismael Sánchez-Osorio, Agustino Martínez-Antonio DOI: 10.1371/journal.pone.0111116 PLoS ONE 9(11):e111116

Complex complexity.Dionisio_{May 22, 2017
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The division of Caulobacter crescentus, a model organism for studying cell cycle and differentiation in bacteria, generates two cell types: swarmer and stalked. To complete its cycle, C. crescentus must first differentiate from the swarmer to the stalked phenotype. An important regulator involved in this process is CtrA, which operates in a gene regulatory network and coordinates many of the interactions associated to the generation of cellular asymmetry. The entire network is shown to be operating close to the critical regime, which means that it is robust enough to perturbations on dynamics of the network, but adaptable to environmental changes.
Dynamical Modeling of the Cell Cycle and Cell Fate Emergence in Caulobacter crescentus César Quiñones-Valles, Ismael Sánchez-Osorio, Agustino Martínez-Antonio DOI: 10.1371/journal.pone.0111116 PLoS ONE 9(11):e111116

Complex complexity.Dionisio_{May 22, 2017
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Although the MICAL family members have clearly emerged as essential regulators of actin dynamics in many cellular functions, several important questions need to be addressed.
Emerging roles of MICAL family proteins – from actin oxidation to membrane trafficking during cytokinesis Stéphane Frémont, Guillaume Romet-Lemonne, Anne Houdusse, Arnaud Echard J Cell Sci 130: 1509-1517; doi: 10.1242/jcs.202028

Work in progress... stay tuned. Complex complexity.Dionisio_{May 19, 2017
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Future studies are needed to better understand the differential roles of each Rab-binding site in determining the localization and functions of MICAL proteins in cells. In addition to the factors that determine the localization of MICALs, another key question is to understand how their enzymatic activity is activated to control F-actin disassembly at the right time and place.
Emerging roles of MICAL family proteins – from actin oxidation to membrane trafficking during cytokinesis Stéphane Frémont, Guillaume Romet-Lemonne, Anne Houdusse, Arnaud Echard J Cell Sci 130: 1509-1517; doi: 10.1242/jcs.202028

Complex complexity.Dionisio_{May 19, 2017
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Recently, two independent studies including ours solved the structure of thisMICAL1 domain by X-ray crystallography (Frémont et al., 2017; Rai et al., 2016). Surprisingly, the structure consists of a curved sheet of three helices, exposing two opposite flat surfaces and thus differs from most three-helix folds, which usually form compact bundles.
Emerging roles of MICAL family proteins – from actin oxidation to membrane trafficking during cytokinesis Stéphane Frémont, Guillaume Romet-Lemonne, Anne Houdusse, Arnaud Echard J Cell Sci 130: 1509-1517; doi: 10.1242/jcs.202028

Did somebody say “Surprisingly”? Complex complexity.Dionisio_{May 19, 2017
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It should be pointed out that approximately half of the MICAL1-depleted cells undergo abscission with normal timing, suggesting that additional as-yet-unknown mechanisms must exist in order to clear F-actin from intercellular bridges in the absence of MICAL1 (Frémont et al., 2017).
Emerging roles of MICAL family proteins – from actin oxidation to membrane trafficking during cytokinesis Stéphane Frémont, Guillaume Romet-Lemonne, Anne Houdusse, Arnaud Echard J Cell Sci 130: 1509-1517; doi: 10.1242/jcs.202028

Complex complexity.Dionisio_{May 19, 2017
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Surprisingly, we found that MICAL1 induces rapid depolymerization from both ends of the filaments with no sign of severing [...]
Emerging roles of MICAL family proteins – from actin oxidation to membrane trafficking during cytokinesis Stéphane Frémont, Guillaume Romet-Lemonne, Anne Houdusse, Arnaud Echard J Cell Sci 130: 1509-1517; doi: 10.1242/jcs.202028

Did somebody say “Surprisingly”? Complex complexity.Dionisio_{May 19, 2017
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[...] MsrB1 has a regulatory role as a MICAL1 antagonist in orchestrating actin dynamics and macrophage function [...] Whether SelR and MsrBs also counteract MICAL1 function during cytokinesis is an open question that should be addressed in future studies.
Emerging roles of MICAL family proteins – from actin oxidation to membrane trafficking during cytokinesis Stéphane Frémont, Guillaume Romet-Lemonne, Anne Houdusse, Arnaud Echard J Cell Sci 130: 1509-1517; doi: 10.1242/jcs.202028

Did somebody say "orchestrating"? Complex complexity.Dionisio_{May 19, 2017
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Knowing the precise mechanism of how MICAL proteins act on the actin cytoskeleton and how their activities are fine-tuned in space and time are essential for understanding the physiological functions of MICALs in normal cells, as well as in the context of disease (Wilson et al., 2016).
Emerging roles of MICAL family proteins – from actin oxidation to membrane trafficking during cytokinesis Stéphane Frémont, Guillaume Romet-Lemonne, Anne Houdusse, Arnaud Echard J Cell Sci 130: 1509-1517; doi: 10.1242/jcs.202028

Did somebody say "fine-tuned in space and time"? Complex complexity.Dionisio_{May 19, 2017
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Faithful cell division is crucial for the maintenance of genomic integrity, development and tissue homeostasis. At the end of cell division, cytokinesis drives the physical separation of the two daughter cells. [...] the mechanisms that remove F-actin in the intercellular bridge are not fully understood. Recently, we revealed an unexpected role for oxidoreduction in triggering local actin depolymerization during cytokinesis [...]
Emerging roles of MICAL family proteins – from actin oxidation to membrane trafficking during cytokinesis Stéphane Frémont, Guillaume Romet-Lemonne, Anne Houdusse, Arnaud Echard J Cell Sci 130: 1509-1517; doi: 10.1242/jcs.202028

Did somebody say “unexpected”? Why? Did they expect something else or nothing at all? Complex complexity.Dionisio_{May 19, 2017
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[...] microtubules and actin filaments must be locally disassembled for successful abscission. However, the mechanism that actively removes actin during abscission is poorly understood.
Emerging roles of MICAL family proteins – from actin oxidation to membrane trafficking during cytokinesis Stéphane Frémont, Guillaume Romet-Lemonne, Anne Houdusse, Arnaud Echard J Cell Sci 130: 1509-1517; doi: 10.1242/jcs.202028

Complex complexity.Dionisio_{May 19, 2017
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Cytokinetic abscission is the terminal step of cell division, leading to the physical separation of the two daughter cells. The exact mechanism mediating the final scission of the intercellular bridge connecting the dividing cells is not fully understood, but requires the local constriction of endosomal sorting complex required for transport (ESCRT)-III-dependent helices, as well as remodelling of lipids and the cytoskeleton at the site of abscission.
Emerging roles of MICAL family proteins – from actin oxidation to membrane trafficking during cytokinesis Stéphane Frémont, Guillaume Romet-Lemonne, Anne Houdusse, Arnaud Echard J Cell Sci 130: 1509-1517; doi: 10.1242/jcs.202028

Complex complexity.Dionisio_{May 19, 2017
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Cytokinesis is the terminal step of cell division and leads to the physical separation of daughter cells. [...] MICAL1 binding to Rab35 not only localizes MICAL1 in late cytokinetic bridges, but also activates monooxygenase activity. Oxidoreduction is one of the most fundamental processes in living organisms and plays a pivotal role in metabolic reactions. [...] this study highlights the critical role of controlled actin oxidation in cytoskeleton dynamics and reveals an unexpected role of oxidoreduction in cell division.
Oxidation of F-actin controls the terminal steps of cytokinesis Stéphane Frémont, Hussein Hammich, Jian Bai, Hugo Wioland, Kerstin Klinkert, Murielle Rocancourt, Carlos Kikuti, David Stroebel, Guillaume Romet-Lemonne, Olena Pylypenko, Anne Houdusse & Arnaud Echard Nature Communications 8, Article number: 14528 doi:10.1038/ncomms14528

Did somebody say “unexpected”? Why? Did they expect something else or nothing at all? Complex complexity.Dionisio_{May 18, 2017
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