Cells damage by protein aggregates is one of the causes of amyloid diseases. This study aimed to explore the structural features of cytotoxic amyloid fibrils and to find strategies to reduce their damaging effect. Bovine carbonic anhydrase B (BCAB) was chosen for this work due to high toxicity of its amyloid fibrils.
View Article and Find Full Text PDFThe fungal bioluminescence pathway can be reconstituted in other organisms allowing luminescence imaging without exogenously supplied substrate. The pathway starts from hispidin biosynthesis-a step catalyzed by a large fungal polyketide synthase that requires a posttranslational modification for activity. Here, we report identification of alternative compact hispidin synthases encoded by a phylogenetically diverse group of plants.
View Article and Find Full Text PDFThe discovery of the bioluminescence pathway in the fungus Neonothopanus nambi enabled engineering of eukaryotes with self-sustained luminescence. However, the brightness of luminescence in heterologous hosts was limited by performance of the native fungal enzymes. Here we report optimized versions of the pathway that enhance bioluminescence by one to two orders of magnitude in plant, fungal and mammalian hosts, and enable longitudinal video-rate imaging.
View Article and Find Full Text PDFWe report a systematic comparison of 19 plant promoters and 20 promoter-terminator combinations in two expression systems: agroinfiltration in leaves, and BY-2 plant cell packs. The set of promoters tested comprised those not present in previously published work, including several computationally predicted synthetic promoters validated here for the first time. The expression of EGFP driven by different promoters varied by more than two orders of magnitude and was largely consistent between two tested Nicotiana systems.
View Article and Find Full Text PDFCytotoxicity of amyloid fibrils has been shown to depend on their structure. However, specific features of toxic and non-toxic amyloids remain unclear. Here we focus on the relationship between structural characteristics of the fibrils and their cytotoxicity.
View Article and Find Full Text PDFNon-coding RNAs play a crucial role in various cellular processes in living organisms, and RNA functions heavily depend on molecule structures composed of stems, loops, and various tertiary motifs. Among those, the most frequent are A-minor interactions, which are often involved in the formation of more complex motifs such as kink-turns and pseudoknots. We present a novel classification of A-minors in terms of RNA secondary structure where each nucleotide of an A-minor is attributed to the stem or loop, and each pair of nucleotides is attributed to their relative position within the secondary structure.
View Article and Find Full Text PDFAn amendment to this paper has been published and can be accessed via a link at the top of the paper.
View Article and Find Full Text PDFAutoluminescent plants engineered to express a bacterial bioluminescence gene cluster in plastids have not been widely adopted because of low light output. We engineered tobacco plants with a fungal bioluminescence system that converts caffeic acid (present in all plants) into luciferin and report self-sustained luminescence that is visible to the naked eye. Our findings could underpin development of a suite of imaging tools for plants.
View Article and Find Full Text PDFIn most cases high cytotoxicity is characteristic of aggregates formed during lag phase of amyloid formation, whereas mature fibrils represent the depot of protein molecules incapable of damaging cell membranes. However, new experimental data show that in cases of some proteins the fibrils are the most toxic type of aggregates. Meanwhile, structural characteristics of cytotoxic fibrils and mechanisms of their cell damaging action are insufficiently explored.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
December 2018
Bioluminescence is found across the entire tree of life, conferring a spectacular set of visually oriented functions from attracting mates to scaring off predators. Half a dozen different luciferins, molecules that emit light when enzymatically oxidized, are known. However, just one biochemical pathway for luciferin biosynthesis has been described in full, which is found only in bacteria.
View Article and Find Full Text PDFEffect of sunlight transformed by luminophore-containing materials on cell viability and functional state of the retina was assessed using the photodamage model. Exposure to the luminescent component of light improved viability of NIH 3T3 cells and promoted recovery of electric activity in rabbit retina after photodamage.
View Article and Find Full Text PDFThe action of solar light transformed by special screens has been studied on CD-1 male mice. In the active control group, mice were irradiated through screens absorbing the UV-component. In the experimental group, screens transforming the UV-component into the orange-red light were used.
View Article and Find Full Text PDFMale rats were irradiated by a Korobkov photon light-emitting diode matrix with a maximum irradiation at 612 nm every day 1 h per day for 13 days. After a course of irradiation, the rhythmoinotropic characteristics of the cardiac muscle significantly improved. Exposure to photon radiation initiated an active rearrangement in myocytes as shown by a morphological analysis.
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