Significance Light microscopy advanced our understanding of cellular structure and associated functions. Research has shown that cellular events, such as signal transduction and gene transcription, require the assembly of proteins into specific macromolecular complexes. Traditional biophysical or biochemical methods have not provided direct access to interactions of protein partners in their natural environments but light microscopic techniques allow us to study molecules under physiological conditions. New imaging technologies, coupled with the development of new genetically encoded fluorescent labels and sensors, and the increasing capability of computer software for image acquisition and analysis, have enabled researchers to conduct more sophisticated studies of the functions and processes of protein molecules, ranging from gene expression to second-messenger cascades and intercellular signaling (DelPozo et al., 2002;Struck et al., 1981;Roessel and Brand, 2002;Ting et al., 2001). One highly sensitive and non-invasive method of protein molecular imaging is Forster (fluorescence) resonance energy transfer (FRET) microscopy. FRET is a distance-dependent physical process, where energy is transferred nonradiatively from an excited molecular fluorophore (donor) to another fluorophore (acceptor) by means of intermolecular longrange dipole-dipole coupling. FRET can accurately measure molecular proximity (1-10 nm), typically when donor and acceptor are positioned within the Forster radius (the distance at which half the excitation energy of the donor is transferred to the acceptor, ~3-6 nm). The efficiency of FRET is dependent on the inverse sixth power of intermolecular separation (Forster, 1965;Lakowicz, 1999;Stryer, 1978), making it a sensitive method for investigating a variety of biological phenomena that produce changes in molecular proximity (Cummings et al., 2002;Day et al 2003;Miyawaki et al., 1999;Wallrabe et al., 2003a). If FRET occurs, donor fluorescence is quenched and acceptor fluorescence is sensitized (increased) (Periasamy and Day, 2005). Co-localization of the donor- and acceptor-labeled probes can be seen within ~0.09 um and molecular associations at close distances can be verified.

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National Heart, Lung, and Blood Institute (NHLBI)
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Heart, Lung, and Blood Initial Review Group (HLBP)
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Zaman, Khalequz; Sawczak, Victoria; Zaidi, Atiya et al. (2016) Augmentation of CFTR maturation by S-nitrosoglutathione reductase. Am J Physiol Lung Cell Mol Physiol 310:L263-70
Raffay, Thomas M; Dylag, Andrew M; Di Fiore, Juliann M et al. (2016) S-Nitrosoglutathione Attenuates Airway Hyperresponsiveness in Murine Bronchopulmonary Dysplasia. Mol Pharmacol 90:418-26
Wallrabe, Horst; Sun, Yuansheng; Fang, Xiaolan et al. (2015) Three-color confocal Förster (or fluorescence) resonance energy transfer microscopy: Quantitative analysis of protein interactions in the nucleation of actin filaments in live cells. Cytometry A 87:580-8
Sawczak, Victoria; Getsy, Paulina; Zaidi, Aliya et al. (2015) Novel Approaches for Potential Therapy of Cystic Fibrosis. Curr Drug Targets 16:923-36
Marozkina, Nadzeya V; Wang, Xin-Qun; Stsiapura, Vitali et al. (2015) Phenotype of asthmatics with increased airway S-nitrosoglutathione reductase activity. Eur Respir J 45:87-97
Palmer, Lisa A; Kimberly deRonde; Brown-Steinke, Kathleen et al. (2015) Hypoxia-induced changes in protein s-nitrosylation in female mouse brainstem. Am J Respir Cell Mol Biol 52:37-45
Marozkina, Nadzeya V; Gaston, Benjamin (2015) Nitrogen chemistry and lung physiology. Annu Rev Physiol 77:431-52
Sun, Yuansheng; Periasamy, Ammasi (2015) Localizing protein-protein interactions in living cells using fluorescence lifetime imaging microscopy. Methods Mol Biol 1251:83-107
Chelko, Stephen P; Schmiedt, Chad W; Lewis, Tristan H et al. (2014) Occipital Artery Function during the Development of 2-Kidney, 1-Clip Hypertension in Rats. Int J Vasc Med 2014:659617
Getsy, Paulina M; Davis, Jesse; Coffee, Gregory A et al. (2014) Enhanced non-eupneic breathing following hypoxic, hypercapnic or hypoxic-hypercapnic gas challenges in conscious mice. Respir Physiol Neurobiol 204:147-59

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