Glossar Plant Cell Biology

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ENG	D	Bedeutung

Abbé's Law	Abbé-Regel	describes the relationship between resolution and wavelength: D = λ / N.A.
acquisition	Aufnahme (von Bildern)	collection of microscopical images
active transport	aktiver Transport	transport across a membrane that is driven by external energy (against chemical gradients)
anisotropic	anisotrop	literally "not equal in all directions", i.e. there is a directionality, e.g. in the cell wall expansibility
apotomy	Apotomie	simple form of structured illumination using an optical grid which is moved over the specimen to separate focal and non-focal pixels
aptamers	Aptamere	artificial RNA molecules with defined threedimensional structures used for engineering target molecules in a cell
aquaporins	Aquaporine	membrane channels that transport water or small molecules and increase conductance in case of limitations
artifact	Artefakt (arte factum)	false experimental data produced by problems of methodology or equipment
auxin canalisation	Auxinkanalisierung	the formation of a pattern of auxin flow by global influx and polarised efflux, guides the formation of vasculature
averaging	Mittelung	procedure in confocal microscopy, where subsequent images of a stack are overlaid to improve signal-noise ratio
beam splitter	Farbteiler	interference filter in epifluorescence microscopy that reflects the excitation light, but transmits the fluorescent light
biolistics	Biolistik	from Bio-Ballistics, shooting foreign DNA into cells (can be transient or stable, depending on the vector)
birefringency	Doppelbrechung	different diffraction of polarised light depending on direction, diagnostic property for elongated, polar macromolecules (cellulose)
Bimodal Fluorescence Complementation (BiFC)	Fluoreszenz-Komplementierung	Fluorescence produced by two interaction partners fused to the two halves of a split YFP
bioluminescence	Biolumineszenz	Conversion of chemical energy into light (does not require excitation!), e.g. Aequorin
birefringent	doppelbrechend	different refraction depending on the direction of polarised light, caused by elongated, polar molecules
BODIPY	BODIPY	Boron-DiPyrrromethene based fluorochromes with superior optical properties
Broglie Law	Broglie Gesetz	describes the relationship between wavelength and frequency: their product equals c (velocity of light)
caged compounds	photoaktivierbare Komponenten	bioactive molecules that are inactivated in a chelated "cage" that can be released by a light beam
cameleon	Chamäleon	artificial fluorescent Protein consisting of CFP and YFP connected by a calmodulin linker, used as calcium sensor via FRET
Cavallieri Method	Cavallieri-Methode	Approach of stereology, where the volume of an object is estimated from the relative area in several sections of a z-stack
Caveat	lat. für "man passe auf"	a point in science, where data are easily misinterpreted due to false concepts or experimental ambiguities
cell lineage	Zellabstammungslinie	predictable sequence of cell divisions, in some organism used to control cell differentiation
cell permeating peptides (CPP)	cell permeating peptides	Peptides that can cross the plasma membrane by unknown mechanisms (not by endocytotic uptake!)
chemical engineering	chemical engineering	direct manipulation of biological processes by chemical agents independent of manipulation of DNA
closed pattern formation	geschlossene Musterbildung	a pattern, where first the cells are produced and only then differentiate (typical for animal development)
coassembly assay	Koassemblierungstest	method to purify MAPs by assembly from soluble tubulin
codon usage bias	Codonasymmetrie	Asymmetric occurrence of the different tRNAs conjugated to a given amino acid residue, organism-specific
constitutive promotor	konstitutiver Promotor	promotor that is always active, useful for GFP localisation
cosedimentation assay	Kosedimentierungstest	method to purify MAPs by binding to preassembled (taxol-stabilised) microtubules
coupling	Kopplung	connection between two oscillators, can be strict (physical) or weak (by resonance)
CRAP (colour recovery after photoactivation)	Farberholung nach Photoaktivierung	new approach for protein dynamics like FRAP, but using the colour change of photoconvertible fluorochromes instead
DAPI	DAPI	most important nuclear dye, excited in the near UV, emission in the blue
dichroitic mirror, beam splitter	dichroitischer Spiegel, Farbteiler	Filter that reflects or transmits light depending on wavelength
differentiation	Differenzierung	developmental differences between cell types in adaption to specific functions
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
dynein	Dynein	motor protein moving along microtubules towards the less dynamic minus-end
EB1	EB1	microtubule plus-end marker, stabilises protofilaments against disruption
emission	Emission	Generation of light by an excited fluorochrome by transition from the singulet back to the ground state
endokaryotic Hypothesis	Endokaryon-Hypothese	model that the nucleus formed by an endosymbiotic event from an Archaebacterial ancestor
enhancer trap	enhancer trap	minimal promotor driving a reporter inserted into plants to "trap" tissue-specific active enhancers
entity	Ganzheit	a unit that acts as a whole (individuum)
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
FACS	Fluoreszenz-Zellsortierung	Separation of fluorescently labelled from unlabelled cells/structures in a liquid flow
false causality	falsche Kausalität	correlation of two events that are not causally linked (e.g. stork number and birth rate)
flow cytometry	Fluss-Cytometrie	FACS-based procedure to count cells/nuclei of different DNA-content
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)
FtsZ	FtsZ	filamentous temperature sensitive Z - a cell division factor of bacteria, later found to be homologous to tubulin
germ line	Keimbahn	those cells in a multicellular organism that will generate the propagation cells (contrast: soma)
gigaseal	Gigaohm-Widerstand	in patch clamping electrically tight connection between membrane and pipette to ensure absence of leak current
Green Revolution Genes	Green Revolution Genes	genes with alleles that contributed to the 5-fold yield increase achieved during Green Revolution (1950-1980)
haplodiploidisation	Haplodiploidisierung	rendering a plant homozygous by producing an embryo from pollen, followed by induced diploidisation
heterotcysts	Heterocysten	specialised cells in cyanobacteria that can fix nitrogen
histochemistry	Histochemie	classical staining methods to visualise specific molecules in microscopical specimens
intermediate filaments	Intermediärfilamente	filaments that are intermediate between actin and microtubules, absent in plants (even laminin maintaining the nucleus in animals)
Jablonski scheme	Jablonski Diagramm	graph of energy levels of fluorescent molecules
karyogenesis model	Karyogenese-Modell	model that the nucleus originated de-novo from endomembranes wrapped around the DNA (in contrast to endokaryon model)
katanin	Katanin	microtubule severing protein
kinesin	Kinesin	motor protein moving along microtubules, in most cases towards the dynamic plus-end
laser ablation	Laserablation	destruction of biological structures or cells by a two-photon laser configuration without damaging neighbourhood
laser capture microdissection	Laserbasierte Mikrosektion	excision of a region of interest by a laser and extraction by a low vacuum to collect specific tissues
light-sheet microscopy	Lichtblattmikroskopie	advanced form of confocal microscopy, where a narrow light sheet is generated by lateral irradiation, such that only the focal plane is excited
mechanosensitive channel	mechanosensitiver Kanal	ion channel that opens in response to mechanic strain
microfibril	Mikrofibrille	fiber composed of 36 cellulose chains that are drilled up, element of the plant-cell wall
microfilaments	Mikrofilamente	polymers composed of actin monomers (F-actin), nowadays people use "actin filaments" instead
microtubules	Mikrotubuli (Ez. -tubulus)	polymers composed of heterodimers of a- and b-tubulin
monorail model	Schienenmodell	model for cell-wall anisotropy by kinesin-driven movement of cellulase synthase along microtubules
moonlighting	Schwarzarbeit	second job (in the night), used for secondary functions of proteins (often preadaptations for functional change)
myosin	Myosin	motor protein moving along actin filaments
native promoter	nativer Promoter	the promoter of the expressed gene itself (in contrast to a constitutive promoter)
NLS	Kernsignatur	nuclear localisation sequence, peptide motif responsible for import of proteins into the nucleus
nsPEFs	ns-Pulsfelder	pulsed electrical fields of short duration (ns) and high voltage (1 kV/cm), induce apoptosis
numerical aperture	numerische Apertur	product of sin a (opening angle of objective) and diffraction index n (1 for air, 1.41 for glass)
on-cell configuration	Ganz-Zell-Aufbau	in patch clamp: configuration, where the patch pipette sits on an intact cell
optical tweezers	optische Pinzette	manipulation of small structures by a strong laser beam, based on gradients in diffractive index
optogenetics	Optogenetik	manipulation of cells or organisms by light using light-switchable transgenic constructs
overexpression artifact	Überexpressionsartefakt	effect on a phenotype caused by overexpression of a transgene
PALM microscopy	PALM Mikroskopie	stands for photoactivated laser microscopy, synonym for STORM
pattern formation	Musterbildung	development of a non-random arrangement of different cells

perception	Reizwahrnehmung	start point of signaling by recognition of a signal by a receptor
phalloidin	Phalloidin	secondary compound of the toadstool Amanites phalloides that stabilises F-actin and is used to stain actin filaments
photoactivable	lichtaktivierbar	Fluorochrome, where fluorescence properties can be switched by light different from fluorescence
phragmoplast	Phragmoplast	plant-specific microtubule array that organises the forming cell-plate in telophase
phyllotaxis	Phyllotaxis	the species-dependent patterning of leave positions, following the Fibonacci sequence
pinhole	Lochblende	Small hole in confocal laser microscopy filtering light depending on its geometrical relation with the focal plane
Planck's Law	Plancksches Gesetz	describes the relation between the energy of a photon and its wave number (frequency): E = h ν
polarisation microscopy	Polarisationsmikroskopie	variation of light microscopy using two crossed polarisation filters for visualisation of structural birefringency
polarity	Polarität	a gradient of activity in space, specifically for the cytoskeleton: the direction between (+)- and (-)-end
PPB	Präprophaseband	plant-specific microtubule array at the G2/M transition, predicting axis and symmetry of cell division
probe	Sonde	Specific molecules that are used to investigate a specific biological process
protofilament	Protofilament	row of tubulin dimers, 13 protofilaments form the microtubule
protonema	Protonema (Vz. -nemata)	filamentous gametophyte of ferns, upon blue light irradiation transformed into bidimensional prothallium
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
reaction-diffusion system	Reaktions-Diffusionssystem	processes that are autocatalytic (self-amplifying), but coupled by mutual inhibition, produce self-organisation that is independent of size. The driving model for biological morphogenesis
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
scalar	skalar	independent of direction (not in a gradient)
second messenger	second messenger	signaling from receptors at membrane to nucleus by signaling molecules (kinase cascades, inositpathways, cAMP)
SEM	REM	scanning electron microscopy (Rasterelektronenmikroskopie)
SIM	strukturierte Beleuchtung	approach to use interference patterns for excitation that can be smaller than the diffraction limit.
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
SNAP tag	SNAP tag	coupling of a target molecule to non-peptidic ligands in vivo using a enzymatic tag targeted to nucleotids
soma	Soma	cells constituting the body of an organism, whereas the germ line (Keimbahn) is the cell line yielding the germ cells
Spinning disc microscopy	Drehscheiben-Mikroskopie	confocal technique, where a disc with numerous pinholes rotates to increase scanning speed
stem cells	Stammzelle	cell that divides asymmetrically giving rise to one daughter that maintains the stem cell quality: A gives A+B
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.
stromules	Stromuli	filamentous extensions of plastids (similar to bacterial sex pili), thought to form networks, disproven by mEOS-FP experiments
susception	Suszeption	transformation of a physical stimulus into a energy that can be used for perception
telome	Telom	modular unit of higher plants consisting of vasculature, ground tissue, and epidermis
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.
totipotency	Omnipotenz	the ability of a cell to regenerate an entire organism (animals: germ cells, plants: all cells)
tubulin	Tubulin	building block of microtubules, heterodimer composed of a- and b-subunit
Turing systems	Turingsysteme	reaction diffusion systems that have been recognised by Alan Turing as core principle of biology
two-Photon Laser	Zweiphotonenlaser	two coupled lasers of low energy are focussed such that energy is added up in the focus site
vascular bundle	Leitbündel	transport tissue of land plants consisting of xylem and phloëm
visualise / visualize	markieren	to render a protein or structure visible, usually by specific labels