scholarly journals Role for a Cindr–Arf6 axis in patterning emerging epithelia

2011 ◽  
Vol 22 (23) ◽  
pp. 4513-4526 ◽  
Author(s):  
Ruth I. Johnson ◽  
Alanna Sedgwick ◽  
Crislyn D'Souza-Schorey ◽  
Ross L. Cagan
Keyword(s):  
Cell Motility ◽  
Adaptor Protein ◽  
Time Lapse ◽  
Similar Relationship ◽  
Surface Adhesion ◽  
Cell Movements ◽  
Surface Receptors ◽  
Time Lapse Microscopy ◽  
Gtpase Activating Proteins ◽  
Regulatory Cascade

Patterning of the Drosophila pupal eye is characterized by precise cell movements. In this paper, we demonstrate that these movements require an Arf regulatory cycle that connects surface receptors to actin-based movement. dArf6 activity—regulated by the Arf GTPase–activating proteins (ArfGAPs) dAsap and dArfGAP3 and the Arf GTP exchange factors Schizo and dPsd—promoted large cellular extensions; time-lapse microscopy indicated that these extensions presage cell rearrangements into correct epithelial niches. During this process, the Drosophila eye also requires interactions between surface Neph1/nephrin adhesion receptors Roughest and Hibris, which bind the adaptor protein Cindr (CD2AP). We provide evidence that Cindr forms a physical complex with dArfGAP3 and dAsap. Our data suggest this interaction sequesters ArfGAP function to liberate active dArf6 elsewhere in the cell. We propose that a Neph1/nephrin–Cindr/ArfGAP complex accumulates to limit local Arf6 activity and stabilize adherens junctions. Our model therefore links surface adhesion via an Arf6 regulatory cascade to dynamic modeling of the cytoskeleton, accounting for precise cell movements that organize the functional retinal field. Further, we demonstrate a similar relationship between the mammalian Cindr orthologue CD2AP and Arf6 activity in cell motility assays. We propose that this Cindr/CD2AP-mediated regulation of Arf6 is a widely used mechanism in emerging epithelia.

scholarly journals A Camera Sensors-Based System to Study Drug Effects on In Vitro Motility: The Case of PC-3 Prostate Cancer Cells

Sensors ◽  
2020 ◽  
Vol 20 (5) ◽  
pp. 1531 ◽  
Author(s):  
Maria Colomba Comes ◽  
Arianna Mencattini ◽  
Davide Di Giuseppe ◽  
Joanna Filippi ◽  
Michele D’Orazio ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Cell Motility ◽  
Cancer Cells ◽  
Time Lapse ◽  
Prostate Cancer Cells ◽  
Lab On Chip ◽  
Time Lapse Microscopy ◽  
On Chip ◽  
Cell Trajectory ◽  
Camera Sensors

Cell motility is the brilliant result of cell status and its interaction with close environments. Its detection is now possible, thanks to the synergy of high-resolution camera sensors, time-lapse microscopy devices, and dedicated software tools for video and data analysis. In this scenario, we formulated a novel paradigm in which we considered the individual cells as a sort of sensitive element of a sensor, which exploits the camera as a transducer returning the movement of the cell as an output signal. In this way, cell movement allows us to retrieve information about the chemical composition of the close environment. To optimally exploit this information, in this work, we introduce a new setting, in which a cell trajectory is divided into sub-tracks, each one characterized by a specific motion kind. Hence, we considered all the sub-tracks of the single-cell trajectory as the signals of a virtual array of cell motility-based sensors. The kinematics of each sub-track is quantified and used for a classification task. To investigate the potential of the proposed approach, we have compared the achieved performances with those obtained by using a single-trajectory paradigm with the scope to evaluate the chemotherapy treatment effects on prostate cancer cells. Novel pattern recognition algorithms have been applied to the descriptors extracted at a sub-track level by implementing features, as well as samples selection (a good teacher learning approach) for model construction. The experimental results have put in evidence that the performances are higher when a further cluster majority role has been considered, by emulating a sort of sensor fusion procedure. All of these results highlighted the high strength of the proposed approach, and straightforwardly prefigure its use in lab-on-chip or organ-on-chip applications, where the cell motility analysis can be massively applied using time-lapse microscopy images.

scholarly journals Calpain-mediated Proteolysis of Paxillin Negatively Regulates Focal Adhesion Dynamics and Cell Migration

2011 ◽  
Vol 286 (12) ◽  
pp. 9998-10006 ◽  
Author(s):  
Christa L. Cortesio ◽  
Lindsy R. Boateng ◽  
Timothy M. Piazza ◽  
David A. Bennin ◽  
Anna Huttenlocher
Keyword(s):  
Cell Migration ◽  
Cell Motility ◽  
Focal Adhesion ◽  
Focal Adhesions ◽  
Adaptor Protein ◽  
Time Lapse ◽  
Negative Regulator ◽  
Proteolytic Fragment ◽  
Proteolytic Site ◽  
And Migration

The dynamic turnover of integrin-mediated adhesions is important for cell migration. Paxillin is an adaptor protein that localizes to focal adhesions and has been implicated in cell motility. We previously reported that calpain-mediated proteolysis of talin1 and focal adhesion kinase mediates adhesion disassembly in motile cells. To determine whether calpain-mediated paxillin proteolysis regulates focal adhesion dynamics and cell motility, we mapped the preferred calpain proteolytic site in paxillin. The cleavage site is between the paxillin LD1 and LD2 motifs and generates a C-terminal fragment that is similar in size to the alternative product paxillin delta. The calpain-generated proteolytic fragment, like paxillin delta, functions as a paxillin antagonist and impairs focal adhesion disassembly and migration. We generated mutant paxillin with a point mutation (S95G) that renders it partially resistant to calpain proteolysis. Paxillin-deficient cells that express paxillin S95G display increased turnover of zyxin-containing adhesions using time-lapse microscopy and also show increased migration. Moreover, cancer-associated somatic mutations in paxillin are common in the N-terminal region between the LD1 and LD2 motifs and confer partial calpain resistance. Taken together, these findings suggest a novel role for calpain-mediated proteolysis of paxillin as a negative regulator of focal adhesion dynamics and migration that may function to limit cancer cell invasion.

scholarly journals The Adaptor Protein Lurap1 Is Required for Cell Cohesion during Epiboly Movement in Zebrafish

Biology ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1337
Author(s):  
Ji-Tong Li ◽  
Xiao-Ning Cheng ◽  
Chong Zhang ◽  
De-Li Shi ◽  
Ming Shao
Keyword(s):  
Cell Adhesion ◽  
Adaptor Protein ◽  
Time Lapse ◽  
Underlying Mechanism ◽  
Superficial Layer ◽  
Epithelial Morphogenesis ◽  
Cytoskeletal Organization ◽  
Cell Movements ◽  
Convergence And Extension ◽  
Dynamic Cell

Cell adhesion and polarized cellular behaviors play critical roles in a wide variety of morphogenetic events. In the zebrafish embryo, epiboly represents an important process of epithelial morphogenesis that involves differential cell adhesion and dynamic cell shape changes for coordinated movements of different cell populations, but the underlying mechanism remains poorly understood. The adaptor protein Lurap1 functions to link myotonic dystrophy kinase-related Rac/Cdc42-binding kinase with MYO18A for actomyosin retrograde flow in cell migration. We previously reported that it interacts with Dishevelled in convergence and extension movements during gastrulation. Here, we show that it regulates blastoderm cell adhesion and radial cell intercalation during epiboly. In zebrafish mutant embryos with loss of both maternal and zygotic Lurap1 function, deep cell multilayer of the blastoderm exhibit delayed epiboly with respect to the superficial layer. Time-lapse imaging reveals that these deep cells undergo unstable intercalation, which impedes their expansion over the yolk cell. Cell sorting and adhesion assays indicate reduced cellular cohesion of the blastoderm. These defects are correlated with disrupted cytoskeletal organization in the cortex of blastoderm cells. Thus, the present results extend our previous works by demonstrating that Lurap1 is required for cell adhesion and cell behavior changes to coordinate cell movements during epithelial morphogenesis. They provide insights for a further understanding of the regulation of cytoskeletal organization during gastrulation cell movements.

Description of Chemotactic Cell Migration via Optical Flow Methods

2000 ◽  
Author(s):  
Lisa Choi ◽  
John G. Georgiadis ◽  
Alan R. Horwitz
Keyword(s):  
Image Processing ◽  
Cell Migration ◽  
Optical Flow ◽  
Cell Motility ◽  
Time Lapse ◽  
Objective Analysis ◽  
Processing Methods ◽  
Time Lapse Microscopy ◽  
Displacement Vectors ◽  
Flow Image

Abstract The application of optical flow image processing methods in the quantification of cell migration on substrates is reported here. By extracting pixel-based displacement vectors from time-lapse microscopy, this technique allows the accurate and objective analysis of the cell motility process.

Experience of using time-lapse microscopy in IVF and ICSI programs

2020 ◽  
pp. 47-50
Author(s):  
N. V. Saraeva ◽  
N. V. Spiridonova ◽  
M. T. Tugushev ◽  
O. V. Shurygina ◽  
A. I. Sinitsyna
Keyword(s):  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Selection Procedure ◽  
Time Lapse ◽  
Single Embryo Transfer ◽  
Main Group ◽  
Clinical Pregnancy ◽  
Control Group ◽  
Time Lapse Microscopy

In order to increase the pregnancy rate in the assisted reproductive technology, the selection of one embryo with the highest implantation potential it is very important. Time-lapse microscopy (TLM) is a tool for selecting quality embryos for transfer. This study aimed to assess the benefits of single-embryo transfer of autologous oocytes performed on day 5 of embryo incubation in a TLM-equipped system in IVF and ICSI programs. Single-embryo transfer following incubation in a TLM-equipped incubator was performed in 282 patients, who formed the main group; the control group consisted of 461 patients undergoing single-embryo transfer following a traditional culture and embryo selection procedure. We assessed the quality of transferred embryos, the rates of clinical pregnancy and delivery. The groups did not differ in the ratio of IVF and ICSI cycles, average age, and infertility factor. The proportion of excellent quality embryos for transfer was 77.0% in the main group and 65.1% in the control group (p = 0.001). In the subgroup with receiving eight and less oocytes we noted the tendency of receiving more quality embryos in the main group (р = 0.052). In the subgroup of nine and more oocytes the quality of the transferred embryos did not differ between two groups. The clinical pregnancy rate was 60.2% in the main group and 52.9% in the control group (p = 0.057). The delivery rate was 45.0% in the main group and 39.9% in the control group (p > 0.050).

Sign in / Sign up

Export Citation Format

Share Document