scholarly journals Surface plasmon enhanced energy transfer between gold nanorods and fluorophores: application to endocytosis study and RNA detection

2015 ◽  
Vol 178 ◽  
pp. 383-394 ◽  
Author(s):  
Yinan Zhang ◽  
Guoke Wei ◽  
Jun Yu ◽  
David J. S. Birch ◽  
Yu Chen
Keyword(s):  
Energy Transfer ◽  
Surface Plasmon ◽  
Fluorescence Lifetime ◽  
Gold Nanorods ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Fluorescence Lifetime Imaging ◽  
Time Resolved ◽  
Diagnosis And Prognosis ◽  
Photon Excitation

Previously we have demonstrated surface plasmon enhanced energy transfer between fluorophores and gold nanorods under two-photon excitation using fluorescence lifetime imaging microscopy (FLIM) in both solution and intracellular phases. These studies demonstrated that gold nanoparticle–dye energy transfer combinations are appealing, not only in Förster resonance energy transfer (FRET) imaging, but also energy transfer-based fluorescence lifetime sensing of bio-analytes. Here, we apply this approach to study the internalization of gold nanorods (GNRs) in HeLa cells using the early endosome labeling marker GFP. The observed energy transfer between GFP and the GNRs indicates the involvement of endocytosis in GNR uptake. Moreover, a novel nanoprobe based on oligonucleotide functionalized gold nanorods for nucleic acid sensing via dye–GNRs energy transfer is demonstrated, potentially opening up new possibilities in cancer diagnosis and prognosis. The influence of oligonucleotide design on such nanoprobe performance was studied for the first time using time-resolved fluorescence spectroscopy, bringing new insights to the optimization of the nanoprobe.

Automated multiwell fluorescence lifetime imaging for Förster resonance energy transfer assays and high content analysis

2015 ◽  
Vol 7 (10) ◽  
pp. 4071-4089 ◽  
Author(s):  
Douglas J. Kelly ◽  
Sean C. Warren ◽  
Dominic Alibhai ◽  
Sunil Kumar ◽  
Yuriy Alexandrov ◽  
...  
Keyword(s):  
Content Analysis ◽  
Energy Transfer ◽  
Fluorescence Lifetime ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Förster Resonance Energy Transfer ◽  
Fluorescence Lifetime Imaging ◽  
Lifetime Imaging ◽  
High Content Analysis ◽  
Förster Resonance

An HCA-FLIM instrument is presented alongside exemplar oligomerisation, intermolecular and intramolecular FRET assays that require robust measurement of small lifetime changes.

scholarly journals Screening for protein-protein interactions using Förster resonance energy transfer (FRET) and fluorescence lifetime imaging microscopy (FLIM)

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Anca Margineanu ◽  
Jia Jia Chan ◽  
Douglas J. Kelly ◽  
Sean C. Warren ◽  
Delphine Flatters ◽  
...  
Keyword(s):  
Energy Transfer ◽  
Fluorescence Lifetime ◽  
Protein Interactions ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Forster Resonance Energy Transfer ◽  
Förster Resonance Energy Transfer ◽  
Fluorescence Lifetime Imaging ◽  
Lifetime Imaging ◽  
Förster Resonance

Abstract We present a high content multiwell plate cell-based assay approach to quantify protein interactions directly in cells using Förster resonance energy transfer (FRET) read out by automated fluorescence lifetime imaging (FLIM). Automated FLIM is implemented using wide-field time-gated detection, typically requiring only 10 s per field of view (FOV). Averaging over biological, thermal and shot noise with 100’s to 1000’s of FOV enables unbiased quantitative analysis with high statistical power. Plotting average donor lifetime vs. acceptor/donor intensity ratio clearly identifies protein interactions and fitting to double exponential donor decay models provides estimates of interacting population fractions that, with calibrated donor and acceptor fluorescence intensities, can yield dissociation constants. We demonstrate the application to identify binding partners of MST1 kinase and estimate interaction strength among the members of the RASSF protein family, which have important roles in apoptosis via the Hippo signalling pathway. K D values broadly agree with published biochemical measurements.

scholarly journals A biosensor of local kinesin activity reveals roles of PKC and EB1 in KIF17 activation

2013 ◽  
Vol 203 (3) ◽  
pp. 445-455 ◽  
Author(s):  
Cedric Espenel ◽  
Bipul R. Acharya ◽  
Geri Kreitzer
Keyword(s):  
Energy Transfer ◽  
Fluorescence Lifetime ◽  
Single Cells ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Epithelial Differentiation ◽  
Fluorescence Lifetime Imaging ◽  
Lifetime Data ◽  
Lifetime Imaging ◽  
Phasor Plot

We showed previously that the kinesin-2 motor KIF17 regulates microtubule (MT) dynamics and organization to promote epithelial differentiation. How KIF17 activity is regulated during this process remains unclear. Several kinesins, including KIF17, adopt compact and extended conformations that reflect autoinhibited and active states, respectively. We designed biosensors of KIF17 to monitor its activity directly in single cells using fluorescence lifetime imaging to detect Förster resonance energy transfer. Lifetime data are mapped on a phasor plot, allowing us to resolve populations of active and inactive motors in individual cells. Using this biosensor, we demonstrate that PKC contributes to the activation of KIF17 and that this is required for KIF17 to stabilize MTs in epithelia. Furthermore, we show that EB1 recruits KIF17 to dynamic MTs, enabling its accumulation at MT ends and thus promoting MT stabilization at discrete cellular domains.

Sign in / Sign up

Export Citation Format

Share Document