scholarly journals Fine-grained, nonlinear image registration of live cell movies reveals spatiotemporal organization of diffuse molecular processes

2021 ◽  
Author(s):  
Xuexia Jiang ◽  
Tadamoto Isogai ◽  
Joseph Chi ◽  
Gaudenz Danuser
Keyword(s):  
Image Registration ◽  
Cell Movement ◽  
Spatiotemporal Analysis ◽  
Significant Loss ◽  
Molecular Processes ◽  
Actin Organization ◽  
Fine Grained ◽  
A Cell ◽  
Entire Cell ◽  
Stochastic Time Series

We present an application of non-linear Image registration that allows spatiotemporal analysis of extremely noisy and diffuse molecular processes across the entire cell. To produce meaningful local tracking of the spatially coherent portion of diffuse protein dynamics, we improved upon existing nonlinear image registration to compensate for cell movement and deformation. The registration relies on a subcellular fiducial marker, a cell motion mask, and a topological regularization that enforces diffeomorphism on the registration without significant loss of granularity. We demonstrate the potential of this approach in conjunction with stochastic time-series analysis through the discovery of distinct zones of coherent Profillin dynamics in symmetry-breaking U2OS cells. Further analysis of the resulting Profilin dynamics revealed strong relationships with the underlying actin organization. This study thus provides a framework for extracting functional interactions between cell morphodynamics, protein distributions, and signaling in cells undergoing continuous shape changes.

Novel Spatiotemporal Analysis for Exploring a-Cell Differentiation

Diabetes ◽  
2018 ◽  
Vol 67 (Supplement 1) ◽  
pp. 2128-P
Author(s):  
MIWA HIMURO ◽  
TAKESHI MIYATSUKA ◽  
LUKA SUZUKI ◽  
MASAKI MIURA ◽  
TAKEHIRO KATAHIRA ◽  
...  
Keyword(s):  
Cell Differentiation ◽  
Spatiotemporal Analysis ◽  
A Cell

scholarly journals 3D Bioprinted GelMA Based Models for the Study of Trophoblast Cell Invasion

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Houzhu Ding ◽  
Nicholas P. Illsley ◽  
Robert C. Chang
Keyword(s):  
Cell Invasion ◽  
Functional Limitations ◽  
Cell Movement ◽  
Trophoblast Cell ◽  
Trophoblast Invasion ◽  
Ring Model ◽  
Cell Front ◽  
A Cell ◽  
Practical Tool ◽  
And Migration

AbstractBioprinting is an emerging and promising technique for fabricating 3D cell-laden constructs for various biomedical applications. In this paper, we employed 3D bioprinted GelMA-based models to investigate the trophoblast cell invasion phenomenon, enabling studies of key placental functions. Initially, a set of optimized material and process parameters including GelMA concentration, UV crosslinking time and printing configuration were identified by systematic, parametric study. Following this, a multiple-ring model (2D multi-ring model) was tested with the HTR-8/SVneo trophoblast cell line to measure cell movement under the influence of EGF (chemoattractant) gradients. In the multi-ring model, the cell front used as a cell invasion indicator moves at a rate of 85 ± 33 µm/day with an EGF gradient of 16 µM. However, the rate was dramatically reduced to 13 ± 5 µm/day, when the multi-ring model was covered with a GelMA layer to constrain cells within the 3D environment (3D multi-ring model). Due to the geometric and the functional limitations of multi-ring model, a multi-strip model (2D multi-strip model) was developed to investigate cell movement in the presence and absence of the EGF chemoattractant. The results show that in the absence of an overlying cell-free layer of GelMA, movement of the cell front shows no significant differences between control and EGF-stimulated rates, due to the combination of migration and proliferation at high cell density (6 × 106 cells/ml) near the GelMA surface. When the model was covered by a layer of GelMA (3D multi-strip model) and migration was excluded, EGF-stimulated cells showed an invasion rate of 21 ± 3 µm/day compared to the rate for unstimulated cells, of 5 ± 4 µm/day. The novel features described in this report advance the use of the 3D bioprinted placental model as a practical tool for not only measurement of trophoblast invasion but also the interaction of invading cells with other tissue elements.

scholarly journals Fine-Grained Spatiotemporal Analysis of the Impact of Restricting Factories, Motor Vehicles, and Fireworks on Air Pollution

2020 ◽  
Vol 17 (13) ◽  
pp. 4828
Author(s):  
Mei Yang ◽  
Hong Fan ◽  
Kang Zhao
Keyword(s):  
Air Pollution ◽  
Air Quality ◽  
Spatiotemporal Analysis ◽  
Yangtze River Delta ◽  
Influential Factors ◽  
Motor Vehicles ◽  
Emission Scenarios ◽  
Fine Grained ◽  
The Impact ◽  
Pm2.5 Concentration

Aiming at improving the air quality and protecting public health, policies such as restricting factories, motor vehicles, and fireworks have been widely implemented. However, fine-grained spatiotemporal analysis of these policies’ effectiveness is lacking. This paper collected the hourly meteorological and PM2.5 data for three typical emission scenarios in Hubei, Beijing–Tianjin–Hebei (BTH), and Yangtze River Delta (YRD). Then, this study simulated the PM2.5 concentration under the same meteorological conditions and different emission scenarios based on a reliable hourly spatiotemporal random forest model ( R 2 exceeded 0.84). Finally, we investigated the fine-grained spatiotemporal impact of restricting factories, vehicles, and fireworks on PM2.5 concentrations from the perspective of hours, days, regions, and land uses, excluding meteorological interference. On average, restricting factories and vehicles reduced the PM2.5 concentration at 02:00, 08:00, 14:00, and 20:00 by 18.57, 16.22, 25.00, and 19.07 μ g / m 3 , respectively. Spatially, it had the highest and quickest impact on Hubei, with a 27.05 μ g / m 3 decrease of PM2.5 concentration and 17 day lag to begin to show significant decline. This was followed by YRD, which experienced a 23.52 μ g / m 3 decrease on average and a 23 day lag. BTH was the least susceptible; the PM2.5 concentration decreased by only 8.2 μ g / m 3 . In addition, influenced by intensive human activities, the cultivated, urban, and rural lands experienced a larger decrease in PM2.5 concentration. These empirical results revealed that restricting factories, vehicles, and fireworks is effective in alleviating air pollution and the effect showed significant spatiotemporal heterogeneity. The policymakers should further investigate influential factors of hourly PM2.5 concentrations, combining with local geographical and social environment, and implement more effective and targeted policies to improve local air quality, especially for BTH and the air quality at morning and night.

scholarly journals A Role for Exocytosis in the Spatial Regulationof Actin Organization

2003 ◽  
Vol 3 ◽  
pp. 1359-1362 ◽  
Author(s):  
Xiang-Dong Gao ◽  
Stefan Albert
Keyword(s):  
Actin Cytoskeleton ◽  
Cellular Functions ◽  
Efficient Organization ◽  
Actin Organization ◽  
Spatial Regulation ◽  
A Cell ◽  
Yeast Mutants

The efficient organization of the actin cytoskeleton is important for many cellular functions. However, how the local actin organization is regulated in a cell is not well understood. By using yeast mutants defective in actin organization and secretion, we demonstrated that exocytosis plays a role in the spatial regulation of actin organization. Our findings suggest that the actin cytoskeleton, exocytosis, and perhaps endocytosis, may depend on each other for efficiency and reinforce each other.

scholarly journals Formin 1 Regulates Microtubule and F-Actin Organization to Support Spermatid Transport During Spermatogenesis in the Rat Testis

Endocrinology ◽  
2016 ◽  
Vol 157 (7) ◽  
pp. 2894-2908 ◽  
Author(s):  
Nan Li ◽  
Dolores D. Mruk ◽  
Elizabeth I. Tang ◽  
Will M. Lee ◽  
Chris K. C. Wong ◽  
...  
Keyword(s):  
Sertoli Cells ◽  
Protein Trafficking ◽  
Cell Shape ◽  
Binding Protein ◽  
Cell Movement ◽  
Seminiferous Epithelium ◽  
Intracellular Protein ◽  
Down Regulation ◽  
Actin Organization ◽  
Support Cell

Formin 1 confers actin nucleation by generating long stretches of actin microfilaments to support cell movement, cell shape, and intracellular protein trafficking. Formin 1 is likely involved in microtubule (MT) dynamics due to the presence of a MT binding domain near its N terminus. Here, formin 1 was shown to structurally interact with α-tubulin, the building block of MT, and also end-binding protein 1 (a MT plus [+]-end-binding protein that stabilizes MT) in the testis. Knockdown of formin 1 in Sertoli cells with an established tight junction barrier was found to induce down-regulation of detyrosinated MT (a stabilized form of MT), and disorganization of MTs, in which MTs were retracted from the cell cortical zone, mediated through a loss of MT polymerization and down-regulation of Akt1/2 signaling kinase. An efficient knockdown of formin 1 in the testis reduced the number of track-like structures conferred by MTs and F-actin considerably, causing defects in spermatid and phagosome transport across the seminiferous epithelium. In summary, formin1 maintains MT and F-actin track-like structures to support spermatid and phagosome transport across the seminiferous epithelium during spermatogenesis.

scholarly journals Capillarity and active cell movement at mesendoderm translocation in the Xenopus gastrula

Development ◽  
2021 ◽  
pp. dev.198960
Author(s):  
Martina Nagel ◽  
Debanjan Barua ◽  
Erich W. Damm ◽  
Jubin Kashef ◽  
Ralf Hofmann ◽  
...  
Keyword(s):  
Close Contact ◽  
Cell Mass ◽  
Cell Movement ◽  
Leading Edge ◽  
Active Cell ◽  
Similar Process ◽  
A Cell ◽  
Tissue Surface Tension ◽  
Tip Cells ◽  
Vertical Shearing

During Xenopus gastrulation, leading edge mesendoderm (LEM) advances animally as wedge-shaped cell mass over the vegetally moving blastocoel roof (BCR). We show that close contact across the BCR-LEM interface correlates with attenuated net advance of the LEM, which is therefore pulled forward by tip cells while the remaining LEM frequently separates from the BCR. Nevertheless, lamellipodia persist on the detached LEM surface. They attach to adjacent LEM cells and depend on PDGF-A, cell surface fibronectin and cadherin. We argue that active cell motility on the LEM surface prevents adverse capillary effects in the liquid LEM tissue as it moves by being pulled. It counters tissue surface tension effects with oriented cell movement and bulges the LEM surface out to keep it close to the curved BCR without attaching to it. Proximity to the BCR is necessary in turn for the maintenance and orientation of lamellipodia that permit mass cell movement with minimal substratum contact. Together with a similar process in epithelial invagination, vertical telescoping, the cell movement at the LEM surface defines a novel type of cell rearrangement, vertical shearing.

scholarly journals AGING OF SOMATIC CELLS AS AN EXAMPLE OF STRUCTURAL CHANGE IN THE VITREOUS BODY WITH AGE

2020 ◽  
Vol 01 (Fall) ◽  
pp. 18-22
Author(s):  
Rasim Hajiyev
Keyword(s):  
Cell Shape ◽  
Somatic Cells ◽  
Vitreous Body ◽  
Empty Space ◽  
Central Nucleus ◽  
Structural Framework ◽  
A Cell ◽  
Entire Cell ◽  
Complete Detachment ◽  
General Organization

Purpose:Based on the literature review and previous data, an analogy is drawn between the structure of the vitreous body and somatic cells. A comparison is made between changes in the vitreous body with age and the aging of somatic cells. Methods: A review of the literature and hypotheses. Results(Hypothesis): With age, the amount of hyaluronic acid and microfibrils decreases and the volume of “empty space” increases, leading to the collapse of the vitreous body and a complete detachment. Let us imagine the vitreous body as a giant cell with a central nucleus. The cytoskeleton permeates the entire cell. The cytoskeleton provides a structural framework for the cell, serving as a framework that determines cell shape and the general organization of the cytoplasm. Importantly, the cytoskeleton is much less rigid and permanent than its name implies. We see the same thing in the microfibrils of the vitreous body.Conclusion:With age, the density of the fibrillarstructure of the vitreous body decreases. This structure is apparently, is an evolutionary intracellular formation that formed as a result of the apoptosis of the mesenchymal cells that form the primary vitreous body. An analogy is drawn between the loss of the density of fibrils of the vitreous body and the density of the cytoskeleton of asomatic cell. The loss of the cytoskeleton of a cell is a fatal process that cannot be stopped. The cytoskeleton cannot hold the nucleus in the center of the cell, whichis why the nucleiof theoldercells are not in the center, but are shifted to the periphery.

scholarly journals An endogenous basis for synchronization manners of the circadian rhythm in proliferating Lemna minor plants

2021 ◽  
Author(s):  
Kenya Ueno ◽  
Shogo Ito ◽  
Tokitaka Oyama
Keyword(s):  
Circadian Rhythm ◽  
Circadian Rhythms ◽  
Lemna Minor ◽  
Spatiotemporal Analysis ◽  
Cell Coupling ◽  
Long Distance ◽  
Detached Leaves ◽  
Circadian Organization ◽  
A Cell ◽  
Local Coupling

AbstractEndogenous circadian rhythms in plants play a role in adaptation to day-night cycles. The circadian clock is a cell-autonomous system that functions through the coordination of time information in the plant body. Synchronization of cellular clocks is based on coordination mechanisms; the synchronization manners in proliferating plants remain unclear. We performed spatiotemporal analysis of the circadian rhythm of fronds (leaf-like plant units) of proliferating Lemna minor plants carrying a circadian bioluminescence reporter, AtCCA1:LUC. Noninvasive observations of the bioluminescence of fast-growing two-dimensional plants allowed us to analyze the circadian rhythms at a cell-level resolution and obtain information regarding frond lineage. We focused on spontaneous circadian organization under constant light conditions for plants with light/dark treatment (LD-grown) or without it (LL-grown). Even fronds developing from an LL-grown parental frond showed coherent circadian rhythms among them. This allowed the maintenance of circadian rhythmicity in proliferating plants. Inside a frond, a centrifugal phase/period pattern was observed in LD-grown plants, whereas various phase patterns with traveling waves were formed in LL-grown plants. These patterns were model-simulated by local coupling of cellular circadian oscillators with different initial synchronous states in fronds. Taken together with similar patterning previously reported for detached leaves of Arabidopsis, it is strongly suggested that local coupling is the primary force for the development of these phase patterns in plants lacking long-distance communication. We propose a basic framework of spontaneous phase patterning with three stages of circadian organization: initial phasing, evolution of patterning, and desynchronization/randomizing of phase, in association with altering cell-cell coupling.

scholarly journals Quantitative Analysis of Plasmodesmata Permeability using Cultured Tobacco BY-2 Cells Entrapped in Microfluidic Chips

2021 ◽  
Author(s):  
Kazunori Shimizu ◽  
Masahiro Kikkawa ◽  
Ryo Tabata ◽  
Daisuke Kurihara ◽  
Ken-ichi Kurotani ◽  
...  
Keyword(s):  
Real Time ◽  
Microfluidic Device ◽  
Cultured Cells ◽  
Cell Movement ◽  
Flow Channel ◽  
Microfluidic Chips ◽  
Isolated Cells ◽  
Cell Clusters ◽  
A Cell ◽  
Channel Structures

AbstractPlasmodesmata are unique channel structures in plants that link the fluid cytoplasm between adjacent cells. Plants have evolved these microchannels to allow trafficking of nutritious substances as well as signaling molecules for intercellular communication. However, tracking the behavior of plasmodesmata in real time is difficult because they are located inside tissues. Hence, we developed a microfluidic device that traps cultured cells and fixes their positions to allow testing of plasmodesmata permeability. The device has 112 tandemly aligned trap zones in the flow channel. Cells of the tobacco line BY-2 were cultured for 7 days and filtered using a sieve and a cell strainer before use to isolate short cell clusters consisting of only a few cells. The isolated cells were introduced into the flow channel, resulting in entrapment of cell clusters at 25 out of 112 trap zones (22.3%). Plasmodesmata permeability was tested from 1 to 4 days after trapping the cells. During this period, the cell numbers increased through cell division. Fluorescence recovery after photobleaching experiments using a transgenic marker line expressing nuclear-localized H2B-GFP demonstrated that cell-to-cell movement of H2B-GFP protein occurred within 200 min of photobleaching. The transport of H2B-GFP protein was not observed when sodium chloride, a compound known to cause plasmodesmata closure, was present in the microfluid channel. Thus, this microfluidic device and one-dimensional plant cell samples allowed us to observe plasmodesmata behavior in real time under controllable conditions.

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