Abstract:
:Extracellular vesicles (EVs) are proposed to play important roles in intercellular communication. Two classes of EVs can be distinguished based on their intracellular origin. Exosomes are generated within endosomes and released when these fuse with the plasma membrane, whereas ectosomes bud directly from the plasma membrane. Studies of EV function have been hindered by limited understanding of their biogenesis. Components of the endosomal sorting complex required for transport (ESCRT) machinery play essential roles in topologically equivalent processes at both the endosome and the plasma membrane and are consistently recovered in EVs, but whether they are generally required to produce EVs is still debated. Here, we study the effects of inhibiting the ESCRT-associated AAA+ ATPase VPS4 on EV release from cultured cells using two methods for EV recovery, differential centrifugation and polyethylene glycol precipitation followed by lectin affinity chromatography. We find that inhibiting VPS4 in HEK293 cells decreases release of EV-associated proteins and miRNA as well as the overall number of EV particles. The tetraspanins CD63 and CD9 are among the most frequently monitored EV proteins, but they differ in their subcellular localization, with CD63 primarily in endosomes and CD9 on the plasma membrane. We find that CD63 and CD9 are enriched in separable populations of EVs that are both sensitive to VPS4 inhibition. Serum stimulation increases release of both types of EVs and is also reduced by inhibiting VPS4. Taken together, our data indicate that VPS4 activity is important for generating exosomes and ectosomes, thereby generally implicating the ESCRT machinery in EV biogenesis.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Jackson CE,Scruggs BS,Schaffer JE,Hanson PIdoi
10.1016/j.bpj.2017.05.032subject
Has Abstractpub_date
2017-09-19 00:00:00pages
1342-1352issue
6eissn
0006-3495issn
1542-0086pii
S0006-3495(17)30571-4journal_volume
113pub_type
评论,杂志文章abstract::We previously used an orthogonal high-throughput screen to select peptides that spontaneously cross synthetic lipid bilayers without bilayer disruption. Many of the 12-residue spontaneous membrane translocating peptides (SMTPs) selected from the library contained a 5-residue consensus motif, LRLLR in positions 5-9. We...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2017.06.070
更新日期:2017-08-22 00:00:00
abstract::Scanning ion conductance microscopy (SICM) is a super-resolution live imaging technique that uses a glass nanopipette as an imaging probe to produce three-dimensional (3D) images of cell surface. SICM can be used to analyze cell morphology at nanoscale, follow membrane dynamics, precisely position an imaging nanopipet...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2016.04.017
更新日期:2016-05-24 00:00:00
abstract::We have developed new methodology for measuring intracellular pH (pHi) in cultured cell monolayers and epithelia by analyzing the emission spectra of the trapped fluorescent pH probe, 1,4-dihydroxyphthalonitrile (1,4-DHPN). This compound is unique since both its acid and base forms possess different fluorescence emiss...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(85)83805-4
更新日期:1985-09-01 00:00:00
abstract::Dendrites of cerebellar Purkinje cells (PCs) respond to brief excitations from parallel fibers with lasting plateau depolarizations. It is unknown whether these plateaus are local events that boost the synaptic signals or they propagate to the soma and directly take part in setting the cell firing dynamics. To address...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2010.04.056
更新日期:2010-07-21 00:00:00
abstract::Crystallographic studies of insulin-protamine complexes, such as neutral protamine Hagedorn (NPH) insulin, have been hampered by high crystal solvent content, small crystal dimensions, and extensive disorder in the protamine molecules. We report herein in situ tapping mode atomic force microscopy (TMAFM) studies of cr...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(00)76609-4
更新日期:2000-01-01 00:00:00
abstract::Proton permeation rates across membranes of a synthetic branch-chained glycolipid, 1,3-di-O-phytanyl-2-O-(beta-D-maltotriosyl)glycerol (Mal3(Phyt)2) as well as a branch-chained phospholipid, diphytanoylphosphatidylcholine (DPhPC) were lower than those of straight-chained lipids such as egg yolk phosphatidylcholine (EP...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(01)75970-X
更新日期:2001-12-01 00:00:00
abstract::Voltage gated potassium channels open and inactivate in response to changes of the voltage across the membrane. After removal of the fast N-type inactivation, voltage gated Shaker K-channels (Shaker-IR) are still able to inactivate through a poorly understood closure of the ion conduction pore. This, usually slower, i...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.060152
更新日期:2005-08-01 00:00:00
abstract::The dynamics of proton transfer between the surface of purple membrane and the aqueous bulk have recently been investigated by the Laser Induced Proton Pulse Method. Following a Delta-function release of protons to the bulk, the system was seen to regain its state of equilibrium within a few hundreds of microseconds. ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(03)74887-5
更新日期:2003-01-01 00:00:00
abstract::The high gradient magnetic separation technique has been applied to separate paramagnetic erythrocytes from a cell suspension that also contained diamagnetic cells. Paramagnetism was induced in the red blood cells by oxidizing the iron atoms in the cell hemoglobin to the ferric state (methemoglobin). Diamagnetic cells...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(78)85482-4
更新日期:1978-05-01 00:00:00
abstract::Dielectrophoresis and electrorotation are commonly used to measure dielectric properties and membrane electrical parameters of biological cells. We have derived quantitative relationships for several critical points, defined in Fig. A 1, which characterize the dielectrophoretic spectrum and the electrorotational spect...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(91)82109-9
更新日期:1991-10-01 00:00:00
abstract::It is shown that if x(t) is the solution of a second order differential equation, with real negative characteristic roots (not necessarily distinct), which exhibits an extremum at t = T, then T|x(T)|/|A| [UNK] 1/e where A is the area under the x(t) curve. This result is compared to a special case previously derived by...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/s0006-3495(61)86910-5
更新日期:1961-09-01 00:00:00
abstract::The opening of basepairs plays a key role in DNA replication and transcription, and in the action of DNA repair and modification enzymes. In this article, we have used proton exchange to define the energetics of the pathways for basepair opening in two DNA 17-mer duplexes. The rates of exchange of imino protons with s...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.105.065763
更新日期:2005-11-01 00:00:00
abstract::A useful technique in studying the saturation of hemoglobin in erythrocytes or myoglobin in tissue is cryophotometry, in which tissue is frozen for later spectrophotometric analysis. A general question associated with this technique is whether the freezing process alters the chemical state. This paper presents a theor...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(83)84365-3
更新日期:1983-04-01 00:00:00
abstract::A triple mutant of sperm whale myoglobin (Mb) [Leu(B10) --> Tyr, His(E7) --> Gln, and Thr(E10) --> Arg, called Mb-YQR], investigated by stopped-flow, laser photolysis, crystallography, and molecular dynamics (MD) simulations, proved to be quite unusual. Rebinding of photodissociated NO, O2, and CO from within the prot...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(99)77289-9
更新日期:1999-03-01 00:00:00
abstract::Antisense oligonucleotides present a powerful means to inhibit expression of specific genes, but their effectiveness is limited by factors including cellular delivery, biochemical attack, and poor binding to target. We have developed a systems model of the processes required for an antisense oligonucleotide to enter, ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.054080
更新日期:2005-10-01 00:00:00
abstract::A study on clonal growth in Chinese hamster ovary (CHO) cells was conducted after exposure to optical trapping wavelengths using Nd:YAG (1064 nm) and tunable titanium-sapphire (700-990 nm) laser microbeam optical traps. The nuclei of cells were exposed to optical trapping forces at various wavelengths, power densities...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(96)79716-3
更新日期:1996-03-01 00:00:00
abstract::A novel combined approach of molecular dynamics (MD) and Monte Carlo simulations is developed to calculate various free-volume distributions as a function of position in a lipid bilayer membrane at 323 K. The model bilayer consists of 2 x 100 chain molecules with each chain molecule having 15 carbon segments and one h...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(93)81156-1
更新日期:1993-09-01 00:00:00
abstract::In two-color fluorescence correlation spectroscopy (TCFCS), the fluorescence intensities of two fluorescently-labeled species are cross-correlated over time and can be used to identify static and dynamic interactions. Generally, fluorophore labels are chosen that do not undergo Förster resonance energy transfer (FRET)...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(02)75189-8
更新日期:2002-07-01 00:00:00
abstract::The x-ray structure analysis of photosystem I (PS I) crystals at 4-A resolution (Schubert et al., 1997, J. Mol. Biol. 272:741-769) has revealed the distances between the three iron-sulfur clusters, labeled F(X), F(1), and F(2), which function on the acceptor side of PS I. There is a general consensus concerning the as...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(00)76599-4
更新日期:2000-01-01 00:00:00
abstract::Small RNA-mRNA binding is an essential step in RNA interference, an important cellular regulatory process. Calculations of binding free energy have been used in binding site prediction, but the cost of stretching the mRNA loop when the small RNA-mRNA duplex forms requires further exploration. Here, using both polymer ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2012.12.017
更新日期:2013-01-22 00:00:00
abstract::Recent studies have indicated that the tip links and kinocilial links of sensory hair bundles in the inner ear have similar properties and share a common epitope, and that cadherin 23 may also be a component of each link type. Transmission electron microscopy was therefore used to study and compare the fine structure ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.104.049031
更新日期:2004-12-01 00:00:00
abstract::The motility of Amoeba proteus was examined using the technique of passive particle tracking microrheology, with the aid of newly developed particle tracking software, a fast digital camera, and an optical microscope. We tracked large numbers of endogeneous particles in the amoebae, which displayed subdiffusive motion...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1529/biophysj.107.123851
更新日期:2008-04-15 00:00:00
abstract::We study the stochastic dynamics of growth and shrinkage of single actin filaments taking into account insertion, removal, and ATP hydrolysis of subunits either according to the vectorial mechanism or to the random mechanism. In a previous work, we developed a model for a single actin or microtubule filament where hyd...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2009.12.4306
更新日期:2010-04-21 00:00:00
abstract::A new method is presented to measure local cytoplasmic deformation and rate of deformation in motile active neutrophils. The deformation is expressed in terms of biomechanical strains and strain rates. For this purpose small phagocytosed latex microspheres were used as intracellular markers. Planar Lagrangian and Eule...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(90)82379-1
更新日期:1990-08-01 00:00:00
abstract::The interactions of the hydrophobic pulmonary surfactant proteins SP-B and SP-C with 1,2-dipalmitoylphosphatidylcholine in mixed, spread monolayer films have been studied in situ at the air/water interface with the technique of external reflection absorption infrared spectroscopy (IRRAS). SP-C has a mostly alpha-helic...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)80124-4
更新日期:1995-12-01 00:00:00
abstract::Nonlinear optical Stokes ellipsometric (NOSE) microscopy was demonstrated for the analysis of collagen-rich biological tissues. NOSE is based on polarization-dependent second harmonic generation imaging. NOSE was used to access the molecular-level distribution of collagen fibril orientation relative to the local fiber...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2016.05.055
更新日期:2016-10-04 00:00:00
abstract::To investigate the mechanisms by which vesicles of pulmonary surfactant adsorb to an air-liquid interface, we measured the effect of different phospholipids and of their concentration both in the subphase and at the interface on this process. Adsorbing vesicles contained the hydrophobic surfactant proteins mixed with ...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(00)76589-1
更新日期:2000-01-01 00:00:00
abstract::We present a model of cell motility generated by actomyosin contraction of the cell cortex. We identify, analytically, dynamical instabilities of the cortex and show that they yield steady-state cortical flows, which, in turn, can induce cell migration in three-dimensional environments. This mechanism relies on the re...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/j.bpj.2011.07.038
更新日期:2011-09-07 00:00:00
abstract::We describe Franck-Condon simulations of vibrational cooling effects on absorption difference spectra in chlorophyll a (Chl a). The relative contributions of vibrational equilibration in the electronic ground and excited states depend on the pump and probe wavelengths. For Franck-Condon-active vibrational modes exhibi...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(95)80145-1
更新日期:1995-12-01 00:00:00
abstract::The coat protein of tobacco mosaic virus is known to form three different classes of aggregate, depending on environmental conditions, namely helical, disk, and A-protein. Among the disk aggregates, there are four-layer, six-layer, and long stacks, which can be obtained by varying the ionic strength and temperature co...
journal_title:Biophysical journal
pub_type: 杂志文章
doi:10.1016/S0006-3495(98)77818-X
更新日期:1998-01-01 00:00:00