Spectral phasor analysis of LAURDAN fluorescence in live A549 lung cells to study the hydration and time evolution of intracellular lamellar body-like structures

Malacrida, Leonel; Astrada, Soledad; Briva, Arturo; Bollati-Fogolín, Mariela; Gratton, Enrico; Bagatolli, Luís A.

doi:10.1016/j.bbamem.2016.07.017

Cited by 64 publications

(75 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We used a final 1 M solution of LAURDAN for the experiments of fluidity and/or dipolar relaxation (34). Cells were incubated with LAURDAN for 30 min at 37°C.…”

Section: Fluorescence Lifetime Imaging Microscopymentioning

confidence: 99%

StarD5: an ER stress protein regulates plasma membrane and intracellular cholesterol homeostasis

Rodríguez‐Agudo

Malacrida

Kakiyama

et al. 2019

Journal of Lipid Research

Self Cite

View full text Add to dashboard Cite

How plasma membrane (PM) cholesterol is controlled is poorly understood. Ablation of the gene encoding the ER stress steroidogenic acute regulatory-related lipid transfer domain (StarD)5 leads to a decrease in PM cholesterol content, a decrease in cholesterol efflux, and an increase in intracellular neutral lipid accumulation in macrophages, the major cell type that expresses StarD5. ER stress increases StarD5 expression in mouse hepatocytes, which results in an increase in accessible PM cholesterol in WT but not in StarD5−/− hepatocytes. StarD5−/− mice store higher levels of cholesterol and triglycerides, which leads to altered expression of cholesterol-regulated genes. In vitro, a recombinant GST-StarD5 protein transfers cholesterol between synthetic liposomes. StarD5 overexpression leads to a marked increase in PM cholesterol. Phasor analysis of 6-dodecanoyl-2-dimethylaminonaphthalene fluorescence lifetime imaging microscopy data revealed an increase in PM fluidity in StarD5−/− macrophages. Taken together, these studies show that StarD5 is a stress-responsive protein that regulates PM cholesterol and intracellular cholesterol homeostasis.

show abstract

“…We used a final 1 M solution of LAURDAN for the experiments of fluidity and/or dipolar relaxation (34). Cells were incubated with LAURDAN for 30 min at 37°C.…”

Section: Fluorescence Lifetime Imaging Microscopymentioning

confidence: 99%

StarD5: an ER stress protein regulates plasma membrane and intracellular cholesterol homeostasis

Rodríguez‐Agudo

Malacrida

Kakiyama

et al. 2019

Journal of Lipid Research

Self Cite

View full text Add to dashboard Cite

show abstract

“…ese molecules have a dipole moment following their excitation and induce the relaxation of the surrounding water molecules. Hence, they exhibit various fluorescence characteristics according to the degree of solvent relaxation [74,75]. e specificity of the fluorescent probe's location in the lipid membranes has advantages and disadvantages.…”

Section: Experimental Approach: Indirect Observation Of Watermentioning

confidence: 99%

Functional Hydration Behavior: Interrelation between Hydration and Molecular Properties at Lipid Membrane Interfaces

Watanabe

Suga

Umakoshi

2019

Journal of Chemistry

View full text Add to dashboard Cite

Water is an abundant commodity and has various important functions. It stabilizes the structure of biological macromolecules, controls biochemical activities, and regulates interfacial/intermolecular interactions. Common aspects of interfacial water can be obtained by overviewing fundamental functions and properties at different temporal and spatial scales. It is important to understand the hydrogen bonding and structural properties of water and to evaluate the individual molecular species having different hydration properties. Water molecules form hydrogen bonds with biomolecules and contribute to the adjustment of their properties, such as surface charge, hydrophilicity, and structural flexibility. In this review, the fundamental properties of water molecules and the methods used for the analyses of water dynamics are summarized. In particular, the interrelation between the hydration properties, determined by molecules, and the properties of molecules, determined by their hydration properties, are discussed using the lipid membrane as an example. Accordingly, interesting water functions are introduced that provide beneficial information in the fields of biochemistry, medicine, and food chemistry.

show abstract

“…The phasor approach to FLIM has become a popular technique in image analysis (Celli et al, ; Colyer et al, ; Fereidouni, Blab, & Gerritsen, ; Jameson, Gratton, & Hall, ; Malacrida et al, ; Sameni, Malacrida, Tan, & Digman, ; Sena et al, ). The phasor approach was originally conceived for analysis of FLIM data in the frequency domain.…”

Section: Introductionmentioning

confidence: 99%

“…The phasor approach was originally conceived for analysis of FLIM data in the frequency domain. The equations for conversion of the intensity decay into phasor plots have appeared in several publications (Digman, Caiolfa, Zamai, & Gratton, ; James, Ross, Stefl, & Jameson, ; Malacrida et al, ; Malacrida, Gratton, & Jameson, ; Malacrida, Jameson, & Gratton, ; Stefl, James, Ross, & Jameson, ). Although these equations are deceptively simple, the conditions appropriate for the conversion of data obtained in the time domain (typically Time Correlated Single Photon Counting or TCSPC) to phasors should be carefully considered.…”

Section: Introductionmentioning

confidence: 99%

Differences between FLIM phasor analyses for data collected with the Becker and Hickl SPC830 card and with the FLIMbox card

Ranjit

Malacrida

Gratton

2018

Microscopy Res & Technique

Self Cite

View full text Add to dashboard Cite

The phasor approach to FLIM (Fluorescence Lifetime Imaging Microscopy) is becoming popular due to the powerful fit free analysis and the visualization of the decay at each point in images of cells and tissues. However, although several implementation of the method are offered by manufactures of FLIM accessories for microscopes, the details of the conversion of the decay to phasors at each point in an image requires some consideration. Here we show that if the decay is not properly acquired, the apparently simple phasor transformation can provide incorrect phasor plots and the results may be misinterpreted. In particular, we show the disagreement in experimental data acquired on the same samples using the two cards (FLIMbox, frequency domain and Becker & Hickl BH 830, time domain) and the effect produced by using the BH 830 card with different settings. This difference in data acquisition translates to the assignment of phasor components calculated using different acquisition parameters. This effect is already present in the original data that are not acquired with the proper parameters for the phasor conversion. We also show that the difference in the resolution of components already exists in the data acquired in the time domain when used with settings that do not allow acquisition of the fluorescence decay on a sufficient large time scale.

show abstract

Spectral phasor analysis of LAURDAN fluorescence in live A549 lung cells to study the hydration and time evolution of intracellular lamellar body-like structures

Cited by 64 publications

References 58 publications

StarD5: an ER stress protein regulates plasma membrane and intracellular cholesterol homeostasis

StarD5: an ER stress protein regulates plasma membrane and intracellular cholesterol homeostasis

Functional Hydration Behavior: Interrelation between Hydration and Molecular Properties at Lipid Membrane Interfaces

Differences between FLIM phasor analyses for data collected with the Becker and Hickl SPC830 card and with the FLIMbox card

Contact Info

Product

Resources

About