Actin in eukaryotic cells is found in different pools, with filaments being organized into a variety of supramolecular assemblies. To investigate the assembly and functional relationships between different parts of the actin cytoskeleton in one cell, we studied the morphology and dynamics of cables and patches in yeast. The fine structure of actin cables and the manner in which cables disassemble support a model in which cables are composed of a number of overlapping actin filaments. No evidence for intrinsic polarity of cables was found. To investigate to what extent different parts of the actin cytoskeleton depend on each other, we looked for relationships between cables and patches. Patches and cables were often associated, and their polarized distributions were highly correlated. Therefore, patches and cables do appear to depend on each other for assembly and function. Many cell types show rearrangements of the actin cytoskeleton, which can occur via assembly or movement of actin filaments. In our studies, dramatic changes in actin polarization did not include changes in filamentous actin. In addition, the concentration of actin patches was relatively constant as cells grew. Therefore, cells do not have bursts of activity in which new parts of the actin cytoskeleton are created.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2141765 | PMC |
| http://dx.doi.org/10.1083/jcb.142.6.1501 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Energy-based modelling of single actin filament polymerization using bond graphs.
J R Soc Interface
January 2025
Department of Biomedical Engineering, Faculty of Engineering & Information Technology, University of Melbourne, Melbourne, Victoria 3010, Australia.
Bond graphs provide an energy-based methodology for modelling complex systems hierarchically; at the moment, the method allows biological systems with both chemical and electrical subsystems to be modelled. Herein, the bond graph approach is extended to include chemomechanical transduction thus extending the range of biological systems to be modelled. Actin filament polymerization and force generation is used as an example of chemomechanical transduction, and it is shown that the (transformer) bond graph component provides a practical, and conceptually simple, alternative to the Brownian ratchet approach of Peskin, Odell, Oster and Mogilner.
View Article and Find Full Text PDFInteraction and cleavage of cell and plasma proteins by the platelet-aggregating serine protease PA-BJ of Bothrops jararaca venom.
Biochimie
January 2025
Laboratory of Applied Toxinology, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Butantan Institute, São Paulo, Brazil. Electronic address:
PA-BJ is a serine protease present in Bothrops jararaca venom that triggers platelet aggregation and granule secretion by activating the protease-activated receptors PAR-1 and PAR-4, without clotting fibrinogen. These receptors also have a relevant role in endothelial cells, however, the interaction of PA-BJ with other membrane-bound or soluble targets is not known. Here we explored the activity of PA-BJ on endothelial cell receptor, cytoskeleton, and coagulation proteins in vitro, and show the degradation of fibrinogen and protein C, and the limited proteolysis of actin, EPCR, PAR-1, and thrombomodulin.
View Article and Find Full Text PDFGinsenoside Rh2(S) maintains cytoskeleton homeostasis and inhibits pyroptosis to resist cisplatin-induced cardiotoxicity through FGFR1/HRAS axis.
Phytomedicine
January 2025
College of Chinese Medicinal Materials, Jilin Agricultural University, Changchun, Jilin Province, China. Electronic address:
Background: Patients with cancer undergoing cisplatin chemotherapy frequently experience cardiotoxic side effects that significantly affect their prognosis and survival rates. Our study found that Panax ginseng root extract exerted a significant protective effect against cisplatin-induced myocardial cell injury.
Purpose: The present study aims to elucidate the underlying mechanisms by which the bioactive components of Panax ginseng mitigate cisplatin-induced cardiotoxicity (CIC).
VopX, a novel T3SS effector, modulates host actin dynamics.
mBio
January 2025
Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York, USA.
Unlabelled: Pathogenic strains cause cholera using different mechanisms. O1 and O139 serogroup strains use the toxin-co-regulated pilus (TCP) and cholera toxin (CT) for intestinal colonization and to promote secretory diarrhea, while non-O1/non-O139 serogroup strains are typically non-toxigenic and use alternate virulence factors to cause a clinically similar disease. An O39 serogroup, TCP/CT-negative strain, named AM-19226, uses a type III secretion system (T3SS) to translocate more than 10 effector proteins into the host cell cytosol.
View Article and Find Full Text PDFTccP4: a novel effector identified in the strain 1551-2 required for attaching and effacing lesion formation on infected Nck-null cells.
Microbiol Spectr
January 2025
Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, Brazil.
is a pathogen that causes sporadic cases and outbreaks of diarrhea. The main virulence feature of this bacterium is the attaching and effacing (AE) lesion formation on infected intestinal epithelial cells, which is characterized by the formation of pedestal-like structures that are rich in F-actin. The Brazilian 1551-2 strain can recruit F-actin using both the Nck-dependent and the Nck-independent pathways, the latter of which uses an adaptor protein named Tir-cytoskeleton coupling protein (TccP/EspF).
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!