Visualizing the Translocation and Localization of Bacterial Type III Effector Proteins by Using a Genetically Encoded Reporter System.
Applied and Environmental Microbiology 82(9):2700 (2016)
Bacterial type III secretion system (T3SS) effector proteins are critical determinants of infection for many animal and plant pathogens. However, monitoring of the translocation and delivery of these important virulence determinants has proved to be technically challenging. Here, we used a genet...
Phytochrome A Mediates Blue-Light Enhancement of Second-Positive Phototropism in Arabidopsis.
Frontiers in Plant Science 7:290 (2016)
Hypocotyl phototropism of etiolated Arabidopsis seedlings is primarily mediated by the blue-light receptor kinase phototropin 1 (phot1). Phot1-mediated curvature to continuous unilateral blue light irradiation (0.5 μmol m(-2) s(-1)) is enhanced by overhead pre-treatment with red light (20 μmol m...
Lighting Up Clostridium Difficile: Reporting Gene Expression Using Fluorescent Lov Domains.
Scientific reports 6:23463 (2016)
The uses of fluorescent reporters derived from green fluorescent protein have proved invaluable for the visualisation of biological processes in bacteria grown under aerobic conditions. However, their requirement for oxygen has limited their application in obligate anaerobes such as Clostridium ...
Functional characterization of Ostreococcus tauri phototropin.
New Phytologist 209(2):612 (2016)
Phototropins (phots) regulate a range of adaptive processes in plants that serve to optimize photosynthetic efficiency and promote growth. Light sensing by Arabidopsis thaliana phots is predominantly mediated by the Light, Oxygen and Voltage sensing 2 (LOV2) flavin-binding motif located within t...
U.K. guidelines on the management of variceal haemorrhage in cirrhotic patients.
Gut 64(11):1680 (2015)
These updated guidelines on the management of variceal haemorrhage have been commissioned by the Clinical Services and Standards Committee (CSSC) of the British Society of Gastroenterology (BSG) under the auspices of the liver section of the BSG. The original guidelines which this document super...
LOV-based reporters for fluorescence imaging.
Current Opinion in Chemical Biology 27:39 (2015)
Chromophore-binding domains from plant and bacterial photoreceptor proteins have recently gathered increasing attention as new sources of genetically encoded fluorescent proteins (FPs). In particular, FPs based on the flavin-binding LOV (light, oxygen, or voltage sensing) domain offer advantages...
Proton-Coupled Electron Transfer Constitutes the Photoactivation Mechanism of the Plant Photoreceptor UVR8.
Journal of the American Chemical Society 137(25):8113 (2015)
UVR8 is a novel UV-B photoreceptor that regulates a range of plant responses and is already used as a versatile optogenetic tool. Instead of an exogenous chromophore, UVR8 uniquely employs tryptophan side chains to accomplish UV-B photoreception. UV-B absorption by homodimeric UVR8 induces monom...
Optogenetics. Engineering of a light-gated potassium channel.
Science 348(6235):707 (2015)
The present palette of opsin-based optogenetic tools lacks a light-gated potassium (K(+)) channel desirable for silencing of excitable cells. Here, we describe the construction of a blue-light-induced K(+) channel 1 (BLINK1) engineered by fusing the plant LOV2-Jα photosensory module to the small...
Reaction dynamics of the UV-B photosensor UVR8.
Photochemical & Photobiological Sciences 14(5):995 (2015)
UVR8 is a recently discovered ultraviolet-B (UV-B) photoreceptor protein identified in plants and algae. In the dark state, UVR8 exists as a homodimer, whereas UV-B irradiation induces UVR8 monomerization and initiation of signaling. Although the biological functions of UVR8 have been studied, t...
Lipid anchoring of Arabidopsis phototropin 1 to assess the functional significance of receptor internalization: should I stay or should I go?
New Phytologist 206(3):1038 (2015)
The phototropin 1 (phot1) blue light receptor mediates a number of adaptive responses, including phototropism, that generally serve to optimize photosynthetic capacity. Phot1 is a plasma membrane-associated protein, but upon irradiation, a fraction is internalized into the cytoplasm. Although th...
Plant flavoprotein photoreceptors.
Plant and Cell Physiology 56(3):401 (2015)
Plants depend on the surrounding light environment to direct their growth. Blue light (300-500 nm) in particular acts to promote a wide variety of photomorphogenic responses including seedling establishment, phototropism and circadian clock regulation. Several different classes of flavin-based p...
Photoinduced transformation of UVR8 monitored by vibrational and fluorescence spectroscopy.
Photochemical & Photobiological Sciences 14(2):252 (2015)
Tryptophan residues at the dimer interface of the plant photoreceptor UVR8 promote monomerisation after UV-B absorption via a so far unknown mechanism. Using FTIR spectroscopy we assign light-induced structural transitions of UVR8 mainly to amino acid side chains without major transformations of...
Exploring the size limit of protein diffusion through the periplasm in cyanobacterium Anabaena sp. PCC 7120 using the 13 kDa iLOV fluorescent protein.
Research in Microbiology 164(7):710 (2013)
In the filamentous heterocyst-forming cyanobacterium Anabaena PCC 7120, vegetative cells and heterocysts are interdependent on each other and engaged in exchanges of metabolites for survival when grown under diazotrophic conditions. In this organism, the periplasm appears to be continuous along ...
An infectious recombinant foot-and-mouth disease virus expressing a fluorescent marker protein.
Journal of General Virology 94(Pt 7):1517 (2013)
Foot-and-mouth disease virus (FMDV) is one of the most extensively studied animal pathogens because it remains a major threat to livestock economies worldwide. However, the dynamics of FMDV infection are still poorly understood. The application of reverse genetics provides the opportunity to gen...
Shoot phototropism in higher plants: new light through old concepts.
American Journal of Botany 100(1):35 (2013)
Light is a key environmental factor that drives many aspects of plant growth and development. Phototropism, the reorientation of growth toward or away from light, represents one of these important adaptive processes. Modern studies of phototropism began with experiments conducted by Charles Darw...
Phosphorylation of BLUS1 kinase by phototropins is a primary step in stomatal opening.
Nature Communications 4:2094 (2013)
Opening of stomata in the plant facilitates photosynthetic CO2 fixation and transpiration. Blue-light perception by phototropins (phot1, phot2) activates the plasma membrane H(+)-ATPase, causing stomata to open. Here we describe a regulator that connects these components, a Ser/Thr protein kinas...
Harnessing creativity: creating a business proposal competition for medical students.
Medical Teacher 35(3):261 (2013)
C-terminal region of the UV-B photoreceptor UVR8 initiates signaling through interaction with the COP1 protein.
PNAS 109(40):16366 (2012)
UV-B light initiates photomorphogenic responses in plants. Arabidopsis UV RESISTANCE LOCUS8 (UVR8) specifically mediates these responses by functioning as a UV-B photoreceptor. UV-B exposure converts UVR8 from a dimer to a monomer, stimulates the rapid accumulation of UVR8 in the nucleus, where ...
Structural tuning of the fluorescent protein iLOV for improved photostability.
Journal of Biological Chemistry 287(26):22295 (2012)
Fluorescent proteins derived from light, oxygen, or voltage (LOV) domains offer advantages over green fluorescent protein (GFP) from their small size and efficacy under anaerobic conditions. The flavoprotein improved LOV (iLOV) was engineered from the blue light receptor phototropin as a reporte...
LOV to BLUF: flavoprotein contributions to the optogenetic toolkit.
Molecular Plant 5(3):533 (2012)
Optogenetics is an emerging field that combines optical and genetic approaches to non-invasively interfere with cellular events with exquisite spatiotemporal control. Although it arose originally from neuroscience, optogenetics is widely applicable to the study of many different biological syste...