scholarly journals Phospholipids undergo hop diffusion in compartmentalized cell membrane

2002 ◽  
Vol 157 (6) ◽  
pp. 1071-1082 ◽  
Author(s):  
Takahiro Fujiwara ◽  
Ken Ritchie ◽  
Hideji Murakoshi ◽  
Ken Jacobson ◽  
Akihiro Kusumi
Keyword(s):  
Cell Membrane ◽  
Single Molecule ◽  
Diffusion Rate ◽  
Rat Kidney ◽  
Transmembrane Proteins ◽  
Lateral Diffusion ◽  
Membrane Skeleton ◽  
Single Molecule Level ◽  
Large Unilamellar Vesicles ◽  
Artificial Bilayers

The diffusion rate of lipids in the cell membrane is reduced by a factor of 5–100 from that in artificial bilayers. This slowing mechanism has puzzled cell biologists for the last 25 yr. Here we address this issue by studying the movement of unsaturated phospholipids in rat kidney fibroblasts at the single molecule level at the temporal resolution of 25 μs. The cell membrane was found to be compartmentalized: phospholipids are confined within 230-nm-diameter (ϕ) compartments for 11 ms on average before hopping to adjacent compartments. These 230-nm compartments exist within greater 750-nm-ϕ compartments where these phospholipids are confined for 0.33 s on average. The diffusion rate within 230-nm compartments is 5.4 μm2/s, which is nearly as fast as that in large unilamellar vesicles, indicating that the diffusion in the cell membrane is reduced not because diffusion per se is slow, but because the cell membrane is compartmentalized with regard to lateral diffusion of phospholipids. Such compartmentalization depends on the actin-based membrane skeleton, but not on the extracellular matrix, extracellular domains of membrane proteins, or cholesterol-enriched rafts. We propose that various transmembrane proteins anchored to the actin-based membrane skeleton meshwork act as rows of pickets that temporarily confine phospholipids.

Shear Stress Induces Time- and Domain-Dependent Changes in Lipid Dynamics of Endothelial Cell Membranes

2009 ◽  
Author(s):  
Tristan Tabouillot ◽  
Hari S. Muddana ◽  
Peter J. Butler
Keyword(s):  
Shear Stress ◽  
Endothelial Cell ◽  
Single Molecule ◽  
Plasma Membranes ◽  
Lateral Diffusion ◽  
Tangential Component ◽  
Membrane Microdomains ◽  
Selective Staining ◽  
Single Molecule Level ◽  
Hemodynamic Forces

Endothelial cells (ECs) form the inner lining of the blood vasculature and are exposed to shear stress (τ), the tangential component of hemodynamic forces. ECs transduce τ into biochemical signals possibly via EC-membrane perturbations. We have previously used confocal-FRAP on the DiI-stained plasma membranes of confluent cultured bovine aortic ECs (BAECs) to show that τ induces a rapid, spatially heterogeneous, and time-dependent increase in the lateral diffusion of the fluorescent lipoid probe in the BAEC membrane [1]. We now present evidence at the single molecule level that shear stress differentially perturbs membrane domains that are defined by their selective staining by lipoid dyes (DiI) of differing alkyl chain lengths. This study is the first to directly measure perturbation by shear stress of endothelial cell membrane microdomains.

scholarly journals Barriers for lateral diffusion of transferrin receptor in the plasma membrane as characterized by receptor dragging by laser tweezers: fence versus tether.

1995 ◽  
Vol 129 (6) ◽  
pp. 1559-1574 ◽  
Author(s):  
Y Sako ◽  
A Kusumi
Keyword(s):  
Plasma Membrane ◽  
Transferrin Receptor ◽  
Rat Kidney ◽  
Average Distance ◽  
Lateral Diffusion ◽  
Membrane Skeleton ◽  
Laser Tweezers ◽  
Elastic Structures ◽  
Normal Rat ◽  
And Behavior

Our previous results indicated that the plasma membrane of cultured normal rat kidney fibroblastic cell is compartmentalized for diffusion of receptor molecules, and that long-range diffusion is the result of successive intercompartmental jumps (Sako, Y. and Kusumi, A. 1994. J. Cell Biol. 125:1251-1264). In the present study, we characterized the properties of intercompartmental boundaries by tagging transferrin receptor (TR) with either 210-nm-phi latex or 40-nm-phi colloidal gold particles, and by dragging the particle-TR complexes laterally along the plasma membrane using laser tweezers. Approximately 90% of the TR-particle complexes showed confined-type diffusion with a microscopic diffusion coefficient (Dmicro) of approximately 10(-9) cm2/s and could be dragged past the intercompartmental boundaries in their path by laser tweezers at a trapping force of 0.25 pN for gold-tagged TR and 0.8 pN for latex-tagged TR. At lower dragging forces between 0.05 and 0.1 pN, particle-TR complexes tended to escape from the laser trap at the boundaries, and such escape occurred in both the forward and backward directions of dragging. The average distance dragged was half of the confined distance of TR, which further indicates that particle-TR complexes escape at the compartment boundaries. Since variation in the particle size (40 and 210 nm, the particles are on the extracellular surface of the plasma membrane) hardly affects the diffusion rate and behavior of the particle-TR complexes at the compartment boundaries, and since treatment with cytochalasin D or vinblastin affects the movements of TR (Sako and Kusumi as cited above), argument has been advanced that the boundaries are present in the cytoplasmic domain. Rebound of the particle-TR complexes when they escape from the laser tweezers at the compartment boundaries suggests that the boundaries are elastic structures. These results are consistent with the proposal that the compartment boundaries consist of membrane skeleton or a membrane-associated part of the cytoskeleton (membrane skeleton fence model). Approximately 10% of TR exhibited slower diffusion (Dmicro approximately 10(-10)-10(-11) cm2/s) and binding to elastic structures.

In situ fluorescent profiling of living cell membrane proteins at a single-molecule level

2019 ◽  
Vol 55 (28) ◽  
pp. 4043-4046 ◽  
Author(s):  
Yuanyuan Fan ◽  
Lu Li ◽  
Meng Lu ◽  
Haibin Si ◽  
Bo Tang
Keyword(s):  
Membrane Proteins ◽  
Cell Membrane ◽  
Single Molecule ◽  
Signal Amplification ◽  
Living Cells ◽  
Single Molecule Level ◽  
Visualization Analysis ◽  
Amplification Method ◽  
Cell Membrane Proteins

A signal amplification method is developed for visualization analysis of membrane proteins on living cells at a single-molecule level.

scholarly journals Regulation Mechanisms for Molecular Diffusion in the Cell Membrane by the Membrane Skeleton: A Single Molecule Approach.

MEMBRANE ◽  
2002 ◽  
Vol 27 (2) ◽  
pp. 58-66
Author(s):  
Kotono Murase ◽  
Kenneth Ritchie ◽  
Takahiro Fujiwara ◽  
Ryota Iino ◽  
Chieko Nakada ◽  
...  
Keyword(s):  
Cell Membrane ◽  
Single Molecule ◽  
Molecular Diffusion ◽  
Membrane Skeleton ◽  
Regulation Mechanisms

scholarly journals Dynamics of Bacterial Signal Recognition Particle at a Single Molecule Level

2021 ◽  
Vol 12 ◽  
Author(s):  
Benjamin Mayer ◽  
Meike Schwan ◽  
Luis M. Oviedo-Bocanegra ◽  
Gert Bange ◽  
Kai M. Thormann ◽  
...  
Keyword(s):  
Cell Membrane ◽  
Single Molecule ◽  
Signal Recognition Particle ◽  
Transition States ◽  
High Mobility ◽  
Structured Illumination ◽  
Structured Illumination Microscopy ◽  
Single Molecule Level ◽  
Preferential Localization ◽  
Mobile Fraction

We have studied the localization and dynamics of bacterial Ffh, part of the SRP complex, its receptor FtsY, and of ribosomes in the Gamma-proteobacterium Shewanella putrefaciens. Using structured illumination microscopy, we show that ribosomes show a pronounced accumulation at the cell poles, whereas SRP and FtsY are distributed at distinct sites along the cell membrane, but they are not accumulated at the poles. Single molecule dynamics can be explained by assuming that all three proteins/complexes move as three distinguishable mobility fractions: a low mobility/static fraction may be engaged in translation, medium-fast diffusing fractions may be transition states, and high mobility populations likely represent freely diffusing molecules/complexes. Diffusion constants suggest that SRP and FtsY move together with slow-mobile ribosomes. Inhibition of transcription leads to loss of static molecules and reduction of medium-mobile fractions, in favor of freely diffusing subunits, while inhibition of translation appears to stall the medium mobile fractions. Depletion of FtsY leads to aggregation of Ffh, but not to loss of the medium mobile fraction, indicating that Ffh/SRP can bind to ribosomes independently from FtsY. Heat maps visualizing the three distinct diffusive populations show that while static molecules are mostly clustered at the cell membrane, diffusive molecules are localized throughout the cytosol. The medium fast populations show an intermediate pattern of preferential localization, suggesting that SRP/FtsY/ribosome transition states may form within the cytosol to finally find a translocon.

Atomic Force Microscopy (AFM) for Topography and Recognition Imaging at Single Molecule Level

2013 ◽  
pp. 102-112
Author(s):  
Memed Duman ◽  
Andreas Ebner ◽  
Christian Rankl ◽  
Jilin Tang ◽  
Lilia A. Chtcheglova ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Single Molecule ◽  
Single Molecule Level ◽  
Force Microscopy ◽  
Atomic Force ◽  
Recognition Imaging

Curaxin-Induced DNA Topology Alterations Trigger the Distinct Binding Response of CTCF and FACT at the Single-Molecule Level

Biochemistry ◽  
2021 ◽  
Vol 60 (7) ◽  
pp. 494-499
Author(s):  
Ke Lu ◽  
Cuifang Liu ◽  
Yinuo Liu ◽  
Anfeng Luo ◽  
Jun Chen ◽  
...  
Keyword(s):  
Single Molecule ◽  
Dna Topology ◽  
Single Molecule Level
Sign in / Sign up

Export Citation Format

Share Document