Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.11.8 (FAST)
 758 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Oligodendrocytes can myelinate a variable number of axons in their surroundings; however, the mechanisms underlying axon-oligodendrocyte associations are unknown. We tested the hypothesis that single oligodendrocytes exclusively myelinate axons belonging to the same functional system. Carbocyanine dyes (DiI, FAST DiI) were applied to the sternomastoid muscle of the rat and allowed to transport retrogradely for 4 weeks within the motor axons. Using fluorescence microscopy and iontophoretic injection of Lucifer Yellow (LY), oligodendrocytes were injected in the proximity of retrogradely carbocyanine dye-labeled axons. Using dual channel confocal laser scanning microscopy (CLSM), the three-dimensional relationship between axons and glia was studied. The data indicate that a single oligodendrocyte can myelinate retrogradely labeled axons concomitantly with other, unlabeled axons belonging to apparently different functional systems.
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PMID:Relationship between oligodendrocytes and axons. 946 75

This paper presents Yellow Fluorescence-Activating and absorption-Shifting Tag (Y-FAST), a small monomeric protein tag, half as large as the green fluorescent protein, enabling fluorescent labeling of proteins in a reversible and specific manner through the reversible binding and activation of a cell-permeant and nontoxic fluorogenic ligand (a so-called fluorogen). A unique fluorogen activation mechanism based on two spectroscopic changes, increase of fluorescence quantum yield and absorption red shift, provides high labeling selectivity. Y-FAST was engineered from the 14-kDa photoactive yellow protein by directed evolution using yeast display and fluorescence-activated cell sorting. Y-FAST is as bright as common fluorescent proteins, exhibits good photostability, and allows the efficient labeling of proteins in various organelles and hosts. Upon fluorogen binding, fluorescence appears instantaneously, allowing monitoring of rapid processes in near real time. Y-FAST distinguishes itself from other tagging systems because the fluorogen binding is highly dynamic and fully reversible, which enables rapid labeling and unlabeling of proteins by addition and withdrawal of the fluorogen, opening new exciting prospects for the development of multiplexing imaging protocols based on sequential labeling.
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PMID:Small fluorescence-activating and absorption-shifting tag for tunable protein imaging in vivo. 2692 62

Fluorogen-binding tags, which activate the fluorescence of a specific chromophore (so-called fluorogen) upon reversible binding, have recently been proposed as a way of reducing photobleaching via fluorogen renewal. However, no generic methodology has been proposed to systematically analyze the photodamage of the fluorogen and the protein tag. Using Y-FAST (Yellow Fluorescence-activating and Absorption-Shifting Tag) as a case study we propose here a generic experimental and theoretical approach to assess how fluorogen renewal reduces the apparent photobleaching rate of a fluorogen-binding tag. Y-FAST has its apparent photobleaching rate greatly reduced by fluorogen renewal and its photostability is mainly limited by oxidation of specific residues in the protein scaffold by reactive oxygen species generated by the bound fluorogen. This study sets the groundwork for the optimization of fluorogenic systems, helping guide rational improvements to their photostability.
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PMID:Chromophore Renewal and Fluorogen-Binding Tags: A Match Made to Last. 2895 77

Yellow Fluorescence-Activating and absorption-Shifting Tag (Y-FAST, hereafter called FAST) is a 14 kDa protein tag giving a bright green-yellow fluorescent complex upon interaction with the fluorogenic dye 4-hydroxy-3-methylbenzylidene rhodanine (HMBR). Here, we report a collection of fluorogens enabling tuning of the fluorescence color of FAST from green-yellow to orange and red. Beyond allowing the multicolor imaging of FAST-tagged proteins in live cells, these fluorogens enable dynamic color switching because of FAST's reversible labeling. This unprecedented behavior allows for selective detection of FAST-tagged proteins in cells expressing both green and red fluorescent species through two-color cross-correlation, opening up exciting prospects to overcome spectral crowding and push the frontiers of multiplexed imaging.
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PMID:Dynamic multicolor protein labeling in living cells. 2897 Sep 39