Several cell-surface lipid-tethered proteins exhibit a concentration-independent, cholesterol-sensitive organization of nanoscale clusters and monomers. To understand the mechanism of formation of these clusters, we investigate the spatial distribution and steady-state dynamics of fluorescently tagged GPI-anchored protein nanoclusters using high-spatial and temporal resolution FRET microscopy. These studies reveal a nonrandom spatial distribution of nanoclusters, concentrated in optically resolvable domains. Monitoring the dynamics of recovery of fluorescence intensity and anisotropy, we find that nanoclusters are immobile, and the dynamics of interconversion between nanoclusters and monomers, over a range of temperatures, is spatially heterogeneous and non-Arrhenius, with a sharp crossover coinciding with a reduction in the activity of cortical actin. Cholesterol depletion perturbs cortical actin and the spatial scale and interconversion dynamics of nanoclusters. Direct perturbations of cortical actin activity also affect the construction, dynamics, and spatial organization of nanoclusters. These results suggest a unique mechanism of complexation of cell-surface molecules regulated by cortical actin activity.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7616455 | PMC |
| http://dx.doi.org/10.1016/j.cell.2008.11.032 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Massive endocytosis mechanisms are involved in uptake of HIV-1 particles by monocyte-derived dendritic cells.
Front Immunol
January 2025
IrsiCaixa, Badalona, Spain.
Introduction: HIV-1 exploits dendritic cells (DCs) to spread throughout the body via specific recognition of gangliosides present on the viral envelope by the CD169/Siglec-1 membrane receptor. This interaction triggers the internalization of HIV-1 within a structure known as the sac-like compartment. While the mechanism underlying sac-like compartment formation remains elusive, prior research indicates that the process is clathrin-independent and cell membrane cholesterol-dependent and involves transient disruption of cortical actin.
View Article and Find Full Text PDFRoles for the canonical polarity machinery in the establishment of polarity in budding yeast spores.
Mol Biol Cell
January 2025
Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America.
The yeast buds at sites pre-determined by cortical landmarks deposited during prior budding. During mating between haploid cells in the lab, external pheromone cues override the cortical landmarks to drive polarization and cell fusion. By contrast, in haploid gametes (called spores) produced by meiosis, a pre-determined polarity site drives initial polarized morphogenesis independent of mating partner location.
View Article and Find Full Text PDFMolecular switch of the dendrite-to-spine transport of TDP-43/FMRP-bound neuronal mRNAs and its impairment in ASD.
Cell Mol Biol Lett
January 2025
PhD Program in Medical Neuroscience, Taipei Medical University, Taipei, Taiwan (R.O.C.).
Background: Regulation of messenger RNA (mRNA) transport and translation in neurons is essential for dendritic plasticity and learning/memory development. The trafficking of mRNAs along the hippocampal neuron dendrites remains translationally silent until they are selectively transported into the spines upon glutamate-induced receptor activation. However, the molecular mechanism(s) behind the spine entry of dendritic mRNAs under metabotropic glutamate receptor (mGluR)-mediated neuroactivation and long-term depression (LTD) as well as the fate of these mRNAs inside the spines are still elusive.
View Article and Find Full Text PDFCD44 and Ezrin restrict EGF receptor mobility to generate a novel spatial arrangement of cytoskeletal signaling modules driving bleb-based migration.
bioRxiv
January 2025
Cell and Developmental Biology Center, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, United States.
Cells under high confinement form highly polarized hydrostatic pressure-driven, stable leader blebs that enable efficient migration in low adhesion, environments. Here we investigated the basis of the polarized bleb morphology of metastatic melanoma cells migrating in non-adhesive confinement. Using high-resolution time-lapse imaging and specific molecular perturbations, we found that EGF signaling via PI3K stabilizes and maintains a polarized leader bleb.
View Article and Find Full Text PDFMechanisms of regulated cell death during plant infection by the rice blast fungus Magnaporthe oryzae.
Cell Death Differ
January 2025
The Sainsbury Laboratory, University of East Anglia, Norwich, UK.
Fungi are the most important group of plant pathogens, responsible for many of the world's most devastating crop diseases. One of the reasons they are such successful pathogens is because several fungi have evolved the capacity to breach the tough outer cuticle of plants using specialized infection structures called appressoria. This is exemplified by the filamentous ascomycete fungus Magnaporthe oryzae, causal agent of rice blast, one of the most serious diseases affecting rice cultivation globally.
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!