[20] Giant vesicles, laurdan, and two-photon fluorescence microscopy: Evidence of lipid lateral separation in bilayers

Bagatolli, Luís A.; Sánchez, Susana A.; Hazlett, Theodore L.; Gratton, Enrico

doi:10.1016/s0076-6879(03)60124-2

Cited by 102 publications

(98 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These probes were used to detect the membrane domains in model membranes, as well as in living cells, by two-photon microscopy (Parasassi et al 1997;Bagatolli andGratton 1999, 2000a,b;Dietrich et al 2001;Bagatolli 2003;Bagatolli et al 2003;Kaiser et al 2009). The order of different membrane systems was investigated (Gasecka et al 2009), and new probes to visualize the membrane order were tested by two-photon microscopy (Jin et al 2006;Kim et al 2008;Klymchenko et al 2009).…”

Section: Two-photon Microscopymentioning

confidence: 99%

Fluorescence Techniques to Study Lipid Dynamics

Sezgin¹,

Schwille²

2011

Cold Spring Harbor Perspectives in Biology

View full text Add to dashboard Cite

Biological research has always tremendously benefited from the development of key methodology. In fact, it was the advent of microscopy that shaped our understanding of cells as the fundamental units of life. Microscopic techniques are still central to the elucidation of biological units and processes, but equally important are methods that allow access to the dimension of time, to investigate the dynamics of molecular functions and interactions. Here, fluorescence spectroscopy with its sensitivity to access the single-molecule level, and its large temporal resolution, has been opening up fully new perspectives for cell biology. Here we summarize the key fluorescent techniques used to study cellular dynamics, with the focus on lipid and membrane systems.T o elucidate cellular processes in their native dynamic environment has been one of the main issues in cell biology over the past decades. The lack of appropriate techniques has long been the main limiting step for the research on dynamic systems, because it was impossible to acquire real time information with the well-known biochemical techniques. The key challenge in dynamically observing biological systems is to combine the ability to resolve moderate to very low concentrations of molecules-because they are simply limited in living cells-on relevant timescales. Relevant timescales in cell biology can be minutes and hours, on a systemic level of cell metabolism, down to the microsecond and even nanosecond regime in which molecular and intramolecular rearrangements take place. With respect to lipidic systems, relevant dynamics range from the local movements of lipids by diffusion to the mechanical transformations of whole membranes, spanning several orders of magnitude in time to be covered. Like for other cellular processes, the investigation of lipids and membranes also in general benefited greatly from the introduction of fluorescence microscopy and spectroscopy to biology. After the 1960s, great technological inventions based on the phenomenon of fluorescence were made, such as confocal microscopy, fluorescence recovery after photobleaching (FRAP), fluorescence correlation spectroscopy (FCS), Förster resonance energy transfer (FRET), total internal reflection fluorescence (TIRF), and two-photon microscopy, that not only revolutionized imaging but also yielded access to dynamics on previously inaccessible timescales. Another very big step was certainly taken after the introduction of fluorescent proteins, which again accelerated the use of these techniques in living cells and organisms. Nowadays, the technical advancements of fluorescence-based methods allow us to explore systems as small as single molecules with temporal resolution down to the nanoseconds regime. Lately, even the resolution limit of optical microscopy, for a long time being one of the fundamental barriers in elucidating cellular processes, has been overcome by smart applications of the phenomenon of fluorescence.This article aims at giving a short overview on mainly fluorescence-based metho...

show abstract

Section: Two-photon Microscopymentioning

confidence: 99%

Fluorescence Techniques to Study Lipid Dynamics

Sezgin¹,

Schwille²

2011

Cold Spring Harbor Perspectives in Biology

View full text Add to dashboard Cite

show abstract

“…Laurdan is an environmentally sensitive dye that undergoes a shift in its peak emission wavelength from ϳ500 nm in fluid membranes to ϳ440 nm in ordered membranes (Bagatolli et al, 2003;Gaus et al, 2003). The fluorescence intensity of Laurdan was recorded simultaneously at both peak emission wavelengths, and the normalized ratio representing the GP was used to determine the lipid order in the cell membranes.…”

Section: Plasma Membrane Condensation In Oli-neu Cellsmentioning

confidence: 99%

Rho Regulates Membrane Transport in the Endocytic Pathway to Control Plasma Membrane Specialization in Oligodendroglial Cells

Kippert¹,

Trajković²,

Rajendran³

et al. 2007

J. Neurosci.

View full text Add to dashboard Cite

Differentiation of oligodendrocytes is associated with dramatic changes in plasma membrane structure, culminating in the formation of myelin membrane sheaths. Previous results have provided evidence that regulation of endocytosis may represent a mechanism to control myelin membrane growth. Immature oligodendrocytes have a high rate of clathrin-independent endocytosis for the transport of membrane to late endosomes/lysosomes (LE/Ls). After maturation and receiving signals from neurons, endocytosis is reduced and transport of membrane from LE/Ls to the plasma membrane is triggered. Here, we show that changes in Rho GTPase activity are responsible for switching between these two modes of membrane transport. Strikingly, Rho inactivation did not only reduce the transport of cargo to LE/L but also increased the dynamics of LE/L vesicles. Furthermore, we provide evidence that Rho inactivation results in the condensation of the plasma membrane in a polarized manner. In summary, our data reveal a novel role of Rho: to regulate the flow of membrane and to promote changes in cell surface structure and polarity in oligodendroglial cells. We suggest that Rho inactivation is required to trigger plasma membrane specialization in oligodendrocytes.

show abstract

“…Interestingly, the envelope phase state of both HCCPs and LCCPs, inferred based on generalized polarization (GP) values computed from Laurdan fluorescence, is equivalent to that of raft domains in cellular plasma membranes. Determination of membrane organization through Laurdan GP has an intrinsic advantage: this lipophilic probe distributes equally into fluid or condensed membranes and does not associate with specific fatty acids or phospholipid head groups (33). Therefore, GP values reflect the overall membrane structure and not a specific lipid or protein composition (26).…”

Section: Discussionmentioning

confidence: 99%

Envelope Lipid-packing as a Critical Factor for the Biological Activity and Stability of Alphavirus Particles Isolated from Mammalian and Mosquito Cells

Sousa

Carvalho

Ferreira³

et al. 2011

Journal of Biological Chemistry

View full text Add to dashboard Cite

Alphaviruses are enveloped arboviruses. The viral envelope is derived from the host cell and is positioned between two icosahedral protein shells (T ‫؍‬ 4). Because the viral envelope contains glycoproteins involved in cell recognition and entry, the integrity of the envelope is critical for the success of the early events of infection. Differing levels of cholesterol in different hosts leads to the production of alphaviruses with distinct levels of this sterol loaded in the envelope. Using Mayaro virus, a New World alphavirus, we investigated the role of cholesterol on the envelope of alphavirus particles assembled in either mammalian or mosquito cells. Our results show that although quite different in their cholesterol content, Mayaro virus particles obtained from both cells share a similar high level of lateral organization in their envelopes. This organization, as well as viral stability and infectivity, is severely compromised when cholesterol is depleted from the envelope of virus particles isolated from mammalian cells, but virus particles isolated from mosquito cells are relatively unaffected by cholesterol depletion. We suggest that it is not cholesterol itself, but rather the organization of the viral envelope, that is critical for the biological activity of alphaviruses.

show abstract

[20] Giant vesicles, laurdan, and two-photon fluorescence microscopy: Evidence of lipid lateral separation in bilayers

Cited by 102 publications

References 72 publications

Fluorescence Techniques to Study Lipid Dynamics

Fluorescence Techniques to Study Lipid Dynamics

Rho Regulates Membrane Transport in the Endocytic Pathway to Control Plasma Membrane Specialization in Oligodendroglial Cells

Envelope Lipid-packing as a Critical Factor for the Biological Activity and Stability of Alphavirus Particles Isolated from Mammalian and Mosquito Cells

Contact Info

Product

Resources

About