Glossar Fluoreszenzmikroskopie und Fluoreszente Sonden
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ENG | D | Bedeutung |
artifact | Artefakt (arte factum) | False experimental data produced by problems of methodology or equipment |
Bimodal Fluorescence Complementation (BiFC) | Fluoreszenz-Komplementierung |
Fluorescence produced by two interaction partners fused to the two halves of a split YFP |
biolistics | Biolistik |
from Bio-Ballistics, shooting foreign DNA into cells (can be transient or stable, depending on the vector) |
bioluminescence | Biolumineszenz | Conversion of chemical energy into light (does not require excitation!), e.g. Aequorin |
BODIPY | BODIPY | Boron-DiPyrrromethene based fluorochromes with superior optical properties |
codon usage bias | Codonasymmetrie | Asymmetric occurrence of the different tRNAs conjugated to a given amino acid residue, organism-specific |
dichroitic mirror, beam splitter | dichroitischer Spiegel, Farbteiler | Filter that reflects or transmits light depending on wavelength |
diffraction | Brechung | Change in the direction of a light beam upon transition between different optical density (diffraction index) |
diffraction limit | Auflösungsgrenze | The smallest distance that can be resolved by light microscopy. According to Abbé's Law this limit is defined as ratio of wavelength by numerical aperture. |
DR5 | DR5 | Minimal auxin-responsive promotor made of a 5' mutation of auxin-response element D1-4 of the gene GH3 |
emission | Emission | Generation of light by an excited fluorochrome by transition from the singulet back to the ground state |
epifluorescence | Auflicht-Fluoreszenz | Microscopical set-up, where the excitation light is administered through the objective to the specimen |
evanescent field | evaneszentes Feld | Generation of a weak wave-front during total reflection at the border between different diffraction indices |
excitation | Anregung | Transition of a fluorescent molecule from the ground state into the singulet-state by absorption of a photon |
fluorochrome | Fluoreszenzfarbstoff | Molecule that is excited for fluorescence in the visible range |
FRAP | Fluoreszenz-Regenerierung | Fluorescent Recovery After Photobleaching - approach to measure protein dynamics by bleaching a ROI |
FRET | Förster-Resonanz | stands for fluorescence resonance energy transfer (irradition-free energy transfer between a pair of fluorochromes) |
numerical aperture | numerisches Apertur | product of sin a (opening angle of objective) and diffraction index n (1 for air, 1.41 for glass) |
optical tweezers | optische Pinzette | manipulation of small structures by a strong laser beam, based on gradients in diffractive index |
photoactivable | lichtaktivierbar | Fluorochrome, where fluorescence properties can be switched by light different from fluorescence |
pinhole | Lochblende | Small hole in confocal laser microscopy filtering light depending on its geometrical relation with the focal plane |
probe | Sonde |
Specific molecules that are used to investigate a specific biological process |
ratio-Imaging | Verhältnis-Abbildung | Approach in quantitative image analysis, where pixel intensities obtained at two emission wavelengths are divided to remove the influence of intensity changes not caused by the fluorochrome of interest |
reporter | Reportergen | Gene that is easily detected and reports the activitiy of the promotor under whose control it was placed |
ROI | Zielregion | Region of interest which is in the focus of investigation |
STED | STED | stands for stimulated emission depletion, a specimen is excited by a laser and the excitation is quenched by a second laser. Due to interference of the laser waves, it is possible to generate an excitation spot that is smaller than the diffraction limit |
SIM | strukturierte Beleuchtung | approach to use interference patterns for excitation that can be smaller than the diffraction limit. |
Stokes-Shift | Stokes-Verschiebung | In fluorescence shift of the emitted light to lower energy (longer wavelength), caused by dissipation of heat during transition between different singulet states |
STORM | STORM | stands for 3D stochastic optical reconstruction microscopy, approach to reconstruct the exact position beyond the diffraction limt by using temporal information of a photoactivable fluorochrome. |
TIRF | TIRF | stands for total-internal reflection microscopy using the fact that an evanescent field can penetrate only a very short distance into the sample such that only the uppermost 50-100 nm are excited. |
two-Photon Laser | Zweiphotonenlaser | two coupled lasers of low energy are focussed such that energy is added up in the focus site |
visualise / visualize | markieren | to render a protein or structure visible, usually by specific labels |