Presentation + Paper
22 February 2019 Genetically encoded FRET probes for direct mapping and quantification of intracellular oxygenation level via fluorescence lifetime imaging
Alessio Andreoni, Rozhin Penjweini, Branden Roarke, Marie-Paule Strub, Dan L. Sackett, Jay R. Knutson
Author Affiliations +
Abstract
Molecular oxygen is an important reporter of metabolic and physiological status at the cellular and tissue level, and its concentration is used for the evaluation of many diseases (e.g.: cancer, coronary artery disease). The development of accurate and quantitative methods to measure O2 concentration ([O2]) in living cells, tissues and organisms is challenging and is subject of intense research. We developed a protein-based, fluorescent oxygen sensor that can be expressed directly in cells to monitor [O2] in the intracellular environment. We fused Myoglobin (Myo), a physiological oxygen carrier, with mCherry, a fluorescent protein, to build a fluorescence resonance energy transfer (FRET) pair, Myo-mCherry. The changes in the spectral properties of Myoglobin upon oxygen binding result in changes of the FRETdepleted emission intensity of mCherry, and this effect is detected by monitoring the fluorescence lifetime of the probe. We present here the preparation and characterization of a series of Myo-mCherry variants and mutants that show the versatility of our protein-based approach: the dynamic range of the sensor is tunable and adaptable to different [O2] ranges, as they occur in vitro in different cell lines, the probe is also easily targeted to subcellular compartments. The use of fluorescence overcomes the most common issues of data collection speed and spatial resolution encountered by currently available methods for O2-monitoring. By using Fluorescence Lifetime Imaging Microscopy (FLIM), we show that we can map the oxygenation level of cells in vitro, providing a quantitative assessment of [O2].
Conference Presentation
© (2019) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Alessio Andreoni, Rozhin Penjweini, Branden Roarke, Marie-Paule Strub, Dan L. Sackett, and Jay R. Knutson "Genetically encoded FRET probes for direct mapping and quantification of intracellular oxygenation level via fluorescence lifetime imaging", Proc. SPIE 10882, Multiphoton Microscopy in the Biomedical Sciences XIX, 108820O (22 February 2019); https://doi.org/10.1117/12.2510646
Lens.org Logo
CITATIONS
Cited by 2 scholarly publications.
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Oxygen

Luminescence

Fluorescence lifetime imaging

Proteins

Sensors

Absorption

Fluorescence resonance energy transfer

Back to Top