Abstract:
:Centering and decentering of cellular components is essential for internal organization of cells and their ability to perform basic cellular functions such as division and motility. How cells achieve proper localization of their organelles is still not well-understood, especially in large cells such as oocytes. Here, we study actin-based positioning mechanisms in artificial cells with persistently contracting actomyosin networks, generated by encapsulating cytoplasmic Xenopus egg extracts into cell-sized 'water-in-oil' droplets. We observe size-dependent localization of the contraction center, with a symmetric configuration in larger cells and a polar one in smaller cells. Centering is achieved via a hydrodynamic mechanism based on Darcy friction between the contracting network and the surrounding cytoplasm. During symmetry breaking, transient attachments to the cell boundary drive the contraction center to a polar location. The centering mechanism is cell-cycle dependent and weakens considerably during interphase. Our findings demonstrate a robust, yet tunable, mechanism for subcellular localization. :In order to survive, cells need to react to their environment and change their shape or the localization of their internal components. For example, the nucleus – the compartment that contains the genetic information – is often localized at the center of the cell, but it can also be positioned at the side, for instance when cells move or divide asymmetrically. Cells use multiple positioning mechanisms to move their internal components, including a process that relies on networks of filaments made of a protein known as actin. These networks are constantly remodeled as actin proteins are added and removed from the network. Embedded molecular motors can cause the network of actin filaments to contract and push or pull on the compartments. Yet, the exact way these networks localize components in the cell remains unclear, especially in eggs and other large cells. To investigate this question, Ierushalmi et al. studied the actin networks in artificial cells that they created by enclosing the contents of frog eggs in small droplets surrounded by oil. This showed that the networks contracted either to the center of the cell or to its side. Friction between the contracting actin network and the fluid in the cell generated a force that tends to push the contraction center towards the middle of the cell. In larger cells, this led to the centering of the actin network. In smaller cells however, the network transiently attached to the boundary of the cell, leading the contraction center to be pulled to one side. By developing simpler artificial cells that mimic the positioning processes seen in real-life cells, Ierushalmi et al. discovered new mechanisms for how cells may center or de-center their components. This knowledge may be useful to understand diseases that can emerge when the nucleus or other compartments fail to move to the right location, and which are associated with certain organs developing incorrectly.
journal_name
Elifejournal_title
eLifeauthors
Ierushalmi N,Malik-Garbi M,Manhart A,Abu Shah E,Goode BL,Mogilner A,Keren Kdoi
10.7554/eLife.55368subject
Has Abstractpub_date
2020-04-21 00:00:00issn
2050-084Xpii
55368journal_volume
9pub_type
杂志文章相关文献
eLife文献大全abstract::Unresolved ER stress followed by cell death is recognized as the main cause of a multitude of pathologies including neonatal diabetes. A systematic analysis of the mechanisms of β-cell loss and dysfunction in Akita mice, in which a mutation in the proinsulin gene causes a severe form of permanent neonatal diabetes, sh...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.38472
更新日期:2018-11-09 00:00:00
abstract::Axolotls are uniquely able to mobilize neural stem cells to regenerate all missing regions of the spinal cord. How a neural stem cell under homeostasis converts after injury to a highly regenerative cell remains unknown. Here, we show that during regeneration, axolotl neural stem cells repress neurogenic genes and rea...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.10230
更新日期:2015-11-14 00:00:00
abstract::A major puzzle in biology is how mammalian sperm maintain the correct swimming direction during various phases of the sexual reproduction process. Whilst chemotaxis may dominate near the ovum, it is unclear which cues guide spermatozoa on their long journey towards the egg. Hypothesized mechanisms range from peristalt...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.02403
更新日期:2014-05-27 00:00:00
abstract::Organisms possessing genetic codes with unassigned codons raise the question of how cellular machinery resolves such codons and how this could impact horizontal gene transfer. Here, we use a genomically recoded Escherichia coli to examine how organisms address translation at unassigned UAG codons, which obstruct propa...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.34878
更新日期:2018-10-30 00:00:00
abstract::Some cortical neurons receive highly selective thalamocortical (TC) input, but others do not. Here, we examine connectivity of single thalamic neurons (lateral geniculate nucleus, LGN) onto putative fast-spike inhibitory interneurons in layer 4 of rabbit visual cortex. We show that three 'rules' regulate this connecti...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.60102
更新日期:2020-12-08 00:00:00
abstract::Cavin-3 regulates metabolism and cell proliferation by coordinating the activities of growth factor signalling cascades. ...
journal_title:eLife
pub_type: 评论,杂志文章
doi:10.7554/eLife.01428
更新日期:2013-09-24 00:00:00
abstract::Eukaryotic DNA is packaged into nucleosome arrays, which are repositioned by chromatin remodeling complexes to control DNA accessibility. The Saccharomyces cerevisiae RSC (Remodeling the Structure of Chromatin) complex, a member of the SWI/SNF chromatin remodeler family, plays critical roles in genome maintenance, tra...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.54449
更新日期:2019-12-30 00:00:00
abstract::Although the wiring of the cerebellar cortex appears to be uniform, the neurons in this region of the brain behave more differently from each other than previously thought. ...
journal_title:eLife
pub_type: 评论,杂志文章
doi:10.7554/eLife.03285
更新日期:2014-06-10 00:00:00
abstract::The COVID-19 pandemic has resulted in school closures and distancing requirements that have disrupted both work and family life for many. Concerns exist that these disruptions caused by the pandemic may not have influenced men and women researchers equally. Many medical journals have published papers on the pandemic, ...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.58807
更新日期:2020-06-15 00:00:00
abstract::Myelin, made by oligodendrocytes, is essential for rapid information transfer in the central nervous system. Oligodendrocyte precursors (OPs) receive glutamatergic synaptic input from axons but how this affects their development is unclear. Murine OPs in white matter express AMPA receptor (AMPAR) subunits GluA2, GluA3...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.28080
更新日期:2017-06-13 00:00:00
abstract::After paralyzing spinal cord injury the adult nervous system has little ability to 'heal' spinal connections, and it is assumed to be unable to develop extra-spinal recovery strategies to bypass the lesion. We challenge this assumption, showing that completely spinalized adult rats can recover unassisted hindlimb weig...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.23532
更新日期:2017-06-29 00:00:00
abstract::Synaptic adhesion molecules regulate synapse development and function. However, whether and how presynaptic adhesion molecules regulate postsynaptic NMDAR function remains largely unclear. Presynaptic LAR family receptor tyrosine phosphatases (LAR-RPTPs) regulate synapse development through mechanisms that include tra...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.54224
更新日期:2020-03-06 00:00:00
abstract::The equilibrium between proliferation and quiescence of myogenic progenitor and stem cells is tightly regulated to ensure appropriate skeletal muscle growth and repair. The non-receptor tyrosine phosphatase Ptpn11 (Shp2) is an important transducer of growth factor and cytokine signals. Here we combined complex genetic...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.21552
更新日期:2017-05-02 00:00:00
abstract::Notch signaling plays a crucial role in controling the proliferation and differentiation of stem and progenitor cells during embryogenesis or organogenesis, but its regulation is incompletely understood. BLOS2, encoded by the Bloc1s2 gene, is a shared subunit of two lysosomal trafficking complexes, biogenesis of lysos...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.18108
更新日期:2016-10-10 00:00:00
abstract::Humans and other animals routinely identify and attend to sensory stimuli so as to rapidly acquire rewards or avoid aversive experiences. Emotional arousal, a process mediated by the amygdala, can enhance attention to stimuli in a non-spatial manner. However, amygdala neural activity was recently shown to encode spati...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.04478
更新日期:2014-10-30 00:00:00
abstract::Homologous recombination (HR)-mediated repair of DNA double-strand break (DSB)s is restricted to the post-replicative phases of the cell cycle. Initiation of HR in the G1 phase blocks non-homologous end joining (NHEJ) impairing DSB repair. Completion of HR in G1 cells can lead to the loss-of-heterozygosity (LOH), whic...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.02445
更新日期:2014-04-30 00:00:00
abstract::The expansion of bacterial swarms and the spreading of biofilms can be described by a unified biophysical theory that involves both active and passive processes. ...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.47019
更新日期:2019-04-30 00:00:00
abstract::Single-molecule imaging experiments have shed new light on the methods used by the enzyme RecA to align single- and double-stranded DNA so that double-strand breaks can be repaired. ...
journal_title:eLife
pub_type: 评论,杂志文章
doi:10.7554/eLife.00347
更新日期:2012-12-13 00:00:00
abstract::In order to assess the contribution of a central clock in the hypothalamic suprachiasmatic nucleus (SCN) to circadian behavior and the organization of peripheral clocks, we generated forebrain/SCN-specific Bmal1 knockout mice by using floxed Bmal1 and pan-neuronal Cre lines. The forebrain knockout mice showed >90% del...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.04617
更新日期:2014-12-19 00:00:00
abstract::Animals host multi-species microbial communities (microbiomes) whose properties may result from inter-species interactions; however, current understanding of host-microbiome interactions derives mostly from studies in which elucidation of microbe-microbe interactions is difficult. In exploring how Drosophila melanogas...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.18855
更新日期:2017-01-09 00:00:00
abstract::Iron storage proteins are essential for cellular iron homeostasis and redox balance. Ferritin proteins are the major storage units for bioavailable forms of iron. Some organisms lack ferritins, and it is not known how they store iron. Encapsulins, a class of protein-based organelles, have recently been implicated in m...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.46070
更新日期:2019-07-08 00:00:00
abstract::Examining whether and how the rhythms of limb and breathing movements interact is highly informative about the mechanistic origin of hyperpnoea during running exercise. However, studies have failed to reveal regularities. In particular, whether breathing frequency is inherently proportional to limb velocity and impose...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.61919
更新日期:2020-12-01 00:00:00
abstract::Cancer cells usually exhibit aberrant cell signaling and metabolic reprogramming. However, mechanisms of crosstalk between these processes remain elusive. Here, we show that in an in vivo tumor model expressing oncogenic Drosophila Homeodomain-interacting protein kinase (Hipk), tumor cells display elevated aerobic gly...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.46315
更新日期:2019-07-01 00:00:00
abstract::The Reproducibility Project: Cancer Biology seeks to address growing concerns about reproducibility in scientific research by conducting replications of selected experiments from a number of high-profile papers in the field of cancer biology. The papers, which were published between 2010 and 2012, were selected on the...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.12470
更新日期:2016-03-01 00:00:00
abstract::Unrepaired DNA damage during embryonic development can be potentially inherited by a large population of cells. However, the quality control mechanisms that minimize the contribution of damaged cells to developing embryos remain poorly understood. Here, we uncovered an ATR- and CHK1-mediated transcriptional response t...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.54756
更新日期:2020-03-12 00:00:00
abstract::Sex-optimal diets have different effects on gene expression in female and male flies. ...
journal_title:eLife
pub_type: 评论,杂志文章
doi:10.7554/eLife.51289
更新日期:2019-10-01 00:00:00
abstract::Some DNA viruses overcome plant defenses by producing a suppressor protein that blocks the silencing of viral genes. ...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.11509
更新日期:2015-10-16 00:00:00
abstract::Individuals vary in their responses to stroke and trauma, hampering predictions of outcomes. One reason might be that neural circuits contain hidden variability that becomes relevant only when those individuals are challenged by injury. We found that in the mollusc, Tritonia diomedea, subtle differences between animal...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.02598
更新日期:2014-06-11 00:00:00
abstract::In many plant species, a subset of transcribed genes are characterized by strictly CG-context DNA methylation, referred to as gene body methylation (gbM). The mechanisms that establish gbM are unclear, yet flowering plant species naturally without gbM lack the DNA methyltransferase, CMT3, which maintains CHG (H = A, C...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.47891
更新日期:2019-07-29 00:00:00
abstract::The application of current channelrhodopsin-based optogenetic tools is limited by the lack of strict ion selectivity and the inability to extend the spectra sensitivity into the near-infrared (NIR) tissue transmissible range. Here we present an NIR-stimulable optogenetic platform (termed 'Opto-CRAC') that selectively ...
journal_title:eLife
pub_type: 杂志文章
doi:10.7554/eLife.10024
更新日期:2015-12-08 00:00:00