Search results for "valo"
showing 10 items of 4805 documents
Chromophore-Protein Interplay During the Phytochrome Photocycle Revealed by Step-Scan FTIR Spectroscopy
2018
Phytochrome proteins regulate many photoresponses of plants and microorganisms. Light absorption causes isomerization of the biliverdin chromophore, which triggers a series of structural changes to activate the signaling domains of the protein. However, the structural changes are elusive, and therefore the molecular mechanism of signal transduction remains poorly understood. Here, we apply two-color step-scan infrared spectroscopy to the bacteriophytochrome from Deinococcus radiodurans. We show by recordings in H2O and D2O that the hydrogen bonds to the biliverdin D-ring carbonyl become disordered in the first intermediate (Lumi-R) forming a dynamic microenvironment, then completely detach …
Skeletal muscle-specific methyltransferase METTL21C trimethylates p97 and regulates autophagy-associated protein breakdown
2018
Summary: Protein aggregates and cytoplasmic vacuolization are major hallmarks of multisystem proteinopathies (MSPs) that lead to muscle weakness. Here, we identify METTL21C as a skeletal muscle-specific lysine methyltransferase. Insertion of a β-galactosidase cassette into the Mettl21c mouse locus revealed that METTL21C is specifically expressed in MYH7-positive skeletal muscle fibers. Ablation of the Mettl21c gene reduced endurance capacity and led to age-dependent accumulation of autophagic vacuoles in skeletal muscle. Denervation-induced muscle atrophy highlighted further impairments of autophagy-related proteins, including LC3, p62, and cathepsins, in Mettl21c−/− muscles. In addition, w…
Coordination of the biliverdin D-ring in bacteriophytochromes.
2018
Phytochrome proteins translate light into biochemical signals in plants, fungi and microorganisms. Light cues are absorbed by a bilin chromophore, leading to an isomerization and a rotation of the D-ring. This relays the signal to the protein matrix. A set of amino acids, which is conserved across the phytochrome superfamily, holds the chromophore in the binding pocket. However, the functional role of many of these amino acids is not yet understood. Here, we investigate the hydrogen bonding network which surrounds the D-ring of the chromophore in the resting (Pr) state. We use UV/vis spectroscopy, infrared absorption spectroscopy and X-ray crystallography to compare the photosensory domains…
Regulation of yeast fatty acid desaturase in response to iron deficiency
2017
Unsaturated fatty acids (UFA) are essential components of phospholipids that greatly contribute to the biophysical properties of cellular membranes. Biosynthesis of UFAs relies on a conserved family of iron-dependent fatty acid desaturases, whose representative in the model yeast Saccharomyces cerevisiae is Ole1. OLE1 expression is tightly regulated to adapt UFA biosynthesis and lipid bilayer properties to changes in temperature, and in UFA or oxygen availability. Despite iron deficiency being the most extended nutritional disorder worldwide, very little is known about the mechanisms and the biological relevance of fatty acid desaturases regulation in response to iron starvation. In this re…
Validación del cribado nutricional Malnutrition Screening Tool comparado con la valoración nutricional completa y otros cribados en distintos ámbitos…
2018
Resumen Introducción: los cribados son empleados para detectar el riesgo nutricional y permiten intervenir precozmente e influir en el pronóstico. La herramienta Malnutrition Screening Tool (MST) está validada en paciente hospitalizado y oncológico ambulatorio. Objetivo: analizar por ámbitos sociosanitarios y grupos etarios los cribados MST, Malnutrition Universal Screening Tool (MUST) y Mini Nutritional Assessment-Short Form (MNA-sf) respecto a la valoración nutricional completa (VNC) como patrón de referencia, y evaluar la utilidad del MST en aquellos ámbitos donde no está validado. Material y métodos: se han incluido 815 sujetos ambulatorios, hospitalizados e institucionalizados. Se les …
The essentials of marine biotechnology
2021
Coastal countries have traditionally relied on the existing marine resources (e.g., fishing, food, transport, recreation, and tourism) as well as tried to support new economic endeavors (ocean energy, desalination for water supply, and seabed mining). Modern societies and lifestyle resulted in an increased demand for dietary diversity, better health and well-being, new biomedicines, natural cosmeceuticals, environmental conservation, and sustainable energy sources. These societal needs stimulated the interest of researchers on the diverse and underexplored marine environments as promising and sustainable sources of biomolecules and biomass, and they are addressed by the emerging field of ma…
Activation of Mevalonate Pathway Via LKB1 is Essential for Stability of Treg Cells
2019
Summary: The function of regulatory T (Treg) cells depends on lipid oxidation. However, the molecular mechanism by which Treg cells maintain lipid metabolism after activation remains elusive. Liver kinase B1 (LKB1) acts as a coordinator by linking cellular metabolism to substrate AMP-activated protein kinase (AMPK). We show that deletion of LKB1 in Treg cells exhibited reduced suppressive activity and developed fatal autoimmune inflammation. Mechanistically, LKB1 induced activation of the mevalonate pathway by upregulating mevalonate genes, which was essential for Treg cell functional competency and stability by inducing Treg cell proliferation and suppressing interferon-gamma and interleuk…
Uzskates līdzekļu izmantošana latviešu valodas stundās 1.klasē
2021
Bakalaura darbā tiek risināta problēma par uzskates līdzekļu pareizu izvēli un tādu to efektīvu pielietojumu, lai tie tiešām veicinātu katra skolēna jēgpilnu iesaisti mācībās jeb mācīšanos iedziļinoties. Lai sasniegtu darba mērķi un atbildētu uz pētījuma jautājumu, tiek veikta pedagoģiskās un psiholoģiskās literatūras analīze un veikts empīriskais pētījums. Empīriskajā pētījumā tiek veikta 1. klases skolotāju daļēji strukturēta aptauja, tiek aprobēti bakalaura darba autores pašizgatavotie uzskates līdzekļi un izzinātas skolēnu domas par to ietekmi uz latviešu valodas apguvi.
Sociālo prasmju sekmēšanas iespējas latviešu valodas stundās 1.klasē
2020
Bakalaura darba nosaukums: „Sociālo prasmju sekmēšanas iespējas latviešu valodas stundās 1. klasē.” Darba autore: Tija Veidemane Bakalaura darba vadītāja: Mag. paed. Mārīte Poiša Hipotēze: Sociālās prasmes latviešu valodas stundās, 1.klasē tiek sekmētas, ja: •Latviešu valodas stundās tik nodrošināta metožu daudzveidība; •Tiek ievērotas bērnu intereses, pieredze un vajadzības; •Tiek nodrošināta pozitīva vide. Pētījuma uzdevumi: •Analizēt teorētiskās atziņas par sociālajām prasmēm. •Noskaidrot jaunākā skolas vecumposma bērnu attīstības likumsakarības saistībā ar pētāmo problēmu. •Izzināt sociālo prasmju sekmēšanas veidus un paņēmienus latviešu valodas stundās 1.klasē. Pētījuma metodes: •Liter…
Photochemical mineralization of terrigenous DOC to dissolved inorganic carbon in ocean
2018
When terrigenous dissolved organic carbon (tDOC) rich in chromophoric dissolved organic matter (tCDOM) enters the ocean, solar radiation mineralizes it partially into dissolved inorganic carbon (DIC). This study addresses the amount and the rates of DIC photoproduction from tDOC and the area of ocean required to photomineralize tDOC. We collected water samples from 10 major rivers, mixed them with artificial seawater, and irradiated them with simulated solar radiation to measure DIC photoproduction and the photobleaching of tCDOM. The linear relationship between DIC photoproduction and tCDOM photobleaching was used to estimate the amount of photoproduced DIC from the tCDOM fluxes of the stu…