502 results match your criteria: "Institute of Biology II[Affiliation]"

Research for biopharmaceutical production processes with mammalian cells steadily aims to enhance the cell-specific productivity as a means for optimizing total productivities of bioreactors. Whereas current technologies such as pH, temperature, and osmolality shift require modifications of the cultivation medium, the use of optogenetic switches in recombinant producer cells might be a promising contact-free alternative. However, the proper application of optogenetically engineered cells requires a detailed understanding of basic cellular responses of cells that do not yet contain the optogenetic switches.

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Identification of phosphatases that dephosphorylate the co-chaperone BAG3.

Life Sci Alliance

February 2025

Institute of Biology III, Faculty of Biology, University of Freiburg, Freiburg im Breisgau, Germany

The co-chaperone BAG3 plays critical roles in maintaining cellular proteostasis. It associates with 14-3-3 proteins during the trafficking of aggregation-prone proteins and facilitates their degradation through chaperone-assisted selective autophagy in cooperation with small heat shock proteins. Although reversible phosphorylation regulates BAG3 function, the involved phosphatases remain unknown.

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Article Synopsis
  • - The African catfish is a rapidly growing farmed fish, with production increasing by 20% annually, but it faces challenges from bacterial infections and limitations of plant-based feeds due to antinutritional factors like nonstarch polysaccharides (NSPs).
  • - Supplementing the catfish diet with β-mannanase has the potential to boost growth, improve antioxidant levels, and enhance immunity, but its specific effects need further exploration.
  • - A study revealed that diets enriched with varying levels of β-mannanase improved growth performance and digestive enzyme activity in African catfish, although it did not affect survival rates; notable improvements in gut structure and antioxidant enzyme levels were also recorded.
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The actin-binding protein filamin c (FLNc) is a key mediator in the response of skeletal muscle cells to mechanical stress. In addition to its function as a structural scaffold, FLNc acts as a signaling adaptor which is phosphorylated at S2234 in its mechanosensitive domain 20 (d20) through AKT. Here, we discovered a strong dephosphorylation of FLNc-pS2234 in cultured skeletal myotubes under acute mechanical stress, despite high AKT activity.

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Cryo-EM structure of the human native plasma coagulation factor XIII complex.

Blood

January 2025

Arijit Biswas Laboratory, Institute for Experimental Hematology and Transfusion Medicine, University Hospital Bonn, Bonn, Germany.

The structure of human coagulation factor XIII (FXIII), a heterotetrameric plasma protransglutaminase that covalently cross-links preformed fibrin polymers, remains elusive until today. The heterotetrameric complex is composed of 2 catalytic FXIII-A and 2 protective FXIII-B subunits. Structural etiology underlying FXIII deficiency has so far been derived from crystallographic structures, all of which are currently available for the FXIII-A2 homodimer only.

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The extracellular matrix plays an integrative role in cellular responses in plants, but its contribution to the signalling of extracellular ligands largely remains to be explored. Rapid alkalinisation factors (RALFs) are extracellular peptide hormones that play pivotal roles in various physiological processes. Here, we address a crucial connection between the de-methylesterification machinery of the cell wall component pectin and RALF1 activity.

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Plant growth: The heavy matter of weight-induced plant stem thickening.

Curr Biol

September 2024

Institute of Biology II, University of Freiburg, Schänzlerstr. 1, 79104 Freiburg, Germany. Electronic address:

As plant stems grow taller and heavier, they adapt by promoting stem thickening. A new study shows that weight-induced radial growth is mediated by the auxin efflux transporter PIN3.

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Phytochrome C and Low Temperature Promote the Protein Accumulation and Red-Light Signaling of Phytochrome D.

Plant Cell Physiol

November 2024

Laboratory of Photo and Chronobiology, Institute of Plant Biology, Biological Research Centre, Hungarian Research Network (HUN-REN), Temesvari krt. 62, Szeged H-6726, Hungary.

Light affects almost every aspect of plant development. It is perceived by photoreceptors, among which phytochromes (PHY) are responsible for monitoring the red and far-red spectrum. Arabidopsis thaliana possesses five phytochrome genes (phyA-phyE).

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Spider silk is a tough and versatile biological material combining high tensile strength and extensibility through nanocomposite structure and its nonlinear elastic behaviour. Notably, spiders rarely use single silk fibres in isolation, but instead process them into more complex composites, such as silk fibre bundles, sheets and anchorages, involving a combination of spinneret, leg and body movements. While the material properties of single silk fibres have been extensively studied, the mechanical properties of silk composites and meta-structures are poorly understood and exhibit a hereto largely untapped potential for the bio-inspired design of novel fabrics with outstanding mechanical properties.

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Type IV pili are filamentous appendages found in most bacteria and archaea, where they can support functions such as surface adhesion, DNA uptake, aggregation, and motility. In most bacteria, PilT-family ATPases disassemble adhesion pili, causing them to rapidly retract and produce twitching motility, important for surface colonization. As archaea do not possess PilT homologs, it was thought that archaeal pili cannot retract and that archaea do not exhibit twitching motility.

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This article comments on: Busch A, Gerbracht JV, Davies K, Hoecker U, Hess S. 2024. Comparative transcriptomics elucidates the cellular responses of an aeroterrestrial zygnematophyte to UV radiation.

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Inteins are proteins that excise themselves out of host proteins and ligate the flanking polypeptides in an auto-catalytic process called protein splicing. In nature, inteins are either contiguous or split. In the case of split inteins, the two fragments must first form a complex for the splicing to occur.

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Members of the PII superfamily are versatile, multitasking signaling proteins ubiquitously found in all domains of life. They adeptly monitor and synchronize the cell's carbon, nitrogen, energy, redox, and diurnal states, primarily by binding interdependently to adenyl-nucleotides, including charged nucleotides (ATP, ADP, and AMP) and second messengers such as cyclic adenosine monophosphate (cAMP), cyclic di-adenosine monophosphate (c-di-AMP), and S-adenosylmethionine-AMP (SAM-AMP). These proteins also undergo a variety of posttranslational modifications, such as phosphorylation, adenylation, uridylation, carboxylation, and disulfide bond formation, which further provide cues on the metabolic state of the cell.

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Editorial: Molecular Biology of Archaea - 2022.

Front Microbiol

April 2024

Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA, United States.

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Measurement of Phytochrome B Thermal Reversion Rates In Vivo.

Methods Mol Biol

April 2024

Institute of Biology II, Faculty of Biology, University of Freiburg, Freiburg, Germany.

Thermal reversion of phytochromes is the light-independent but strongly temperature-dependent relaxation of the light-activated Pfr form of phytochromes back into the inactive Pr ground state. The thermal reversion rates of different phytochromes vary considerably. For phytochrome B (phyB), thermal reversion represents a critical parameter affecting phyB activity as it reduces the active phyB Pfr pool, accelerated by increasing temperatures.

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The silent flight of barn owls is associated with wing and feather specialisations. Three special features are known: a serrated leading edge that is formed by free-standing barb tips which appears as a comb-like structure, a soft dorsal surface, and a fringed trailing edge. We used a model of the leading edge comb with 3D-curved serrations that was designed based on 3D micro-scans of rows of barbs from selected barn-owl feathers.

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Synchronized assembly of the oxidative phosphorylation system controls mitochondrial respiration in yeast.

Dev Cell

April 2024

Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, 69120 Heidelberg, Germany; Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany; CIBSS-Centre for Integrative Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany; Network Aging Research, Heidelberg University, 69120 Heidelberg, Germany. Electronic address:

Control of protein stoichiometry is essential for cell function. Mitochondrial oxidative phosphorylation (OXPHOS) presents a complex stoichiometric challenge as the ratio of the electron transport chain (ETC) and ATP synthase must be tightly controlled, and assembly requires coordinated integration of proteins encoded in the nuclear and mitochondrial genome. How correct OXPHOS stoichiometry is achieved is unknown.

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Organ-Specific Microsomes from Dark-Grown Hypocotyls of Arabidopsis thaliana.

Methods Mol Biol

February 2024

Institute of Biology II, Chair group of Molecular Plant Physiology (MoPP), University of Freiburg, Freiburg, Germany.

Article Synopsis
  • The chapter outlines a method for isolating microsomes from the hypocotyl tissue of dark-grown Arabidopsis thaliana.
  • Microsomes are mainly made up of membranes from the endoplasmic reticulum and appear as vesicle-like structures.
  • The authors detail the experimental process, including steps for sample preparation, homogenization, and differential centrifugation, along with quality control measures post-isolation.
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The patch-clamp technique has revolutionized neurophysiology by allowing to study single neuronal excitability, synaptic connectivity, morphology, and the transcriptomic profile. However, the throughput in recordings is limited because of the manual replacement of patch-pipettes after each attempt which are often also unsuccessful. This has been overcome by automated cleaning the tips in detergent solutions, allowing to reuse the pipette for further recordings.

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Model organisms and systems in neuroethology: one hundred years of history and a look into the future.

J Comp Physiol A Neuroethol Sens Neural Behav Physiol

March 2024

Department of Biology, University of Maryland at College Park, College Park, USA.

The Journal of Comparative Physiology lived up to its name in the last 100 years by including more than 1500 different taxa in almost 10,000 publications. Seventeen phyla of the animal kingdom were represented. The honeybee (Apis mellifera) is the taxon with most publications, followed by locust (Locusta migratoria), crayfishes (Cambarus spp.

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The phytochrome (phy) system enables plants to adapt to canopy shade. By sensing the reduction of the red:far-red light ratio in shade, phyA and phyB trigger downstream signalling cascades which eventually lead to enhanced elongation growth. In this study, we show that the F-box protein EID1 takes on an essential function within the shade avoidance response in by repressing phyA action and thereby allowing seedlings to elongate in shade.

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The continuous growth of roots depends on their ability to maintain a balanced ratio between cell production and cell differentiation at the tip. This process is regulated by the hormonal balance of cytokinin and auxin. However, other important regulators, such as plant folates, also play a regulatory role.

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Gravitropism: The LAZY way of intracellular hitchhiking.

Curr Biol

December 2023

Institute of Biology II, Chair of Molecular Plant Physiology (MoPP), University of Freiburg, 79104 Freiburg, Germany; Center for Integrative Biological Signalling Studies (CIBSS), University of Freiburg, 79104 Freiburg, Germany. Electronic address:

Plant gravitropism has fascinated scientists for centuries. A new study provides a major mechanistic update of the so-called starch/statolith hypothesis, revealing how gravity perception is converted into a physiological response.

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The incorporation of non-canonical amino acids (ncAAs) into proteins is a powerful technique used in various research fields. Genetic code expansion (GCE) is the most common way to achieve this: a specific codon is selected to be decoded by a dedicated tRNA orthogonal to the endogenous ones. In the past 30 years, great progress has been made to obtain novel tRNA synthetases (aaRSs) accepting a variety of ncAAs with distinct physicochemical properties, to develop robust in vitro assays or approaches for codon reassignment.

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Article Synopsis
  • ReverseDock is a web server designed for reverse molecular docking, allowing users to dock a single ligand to multiple protein targets easily, contrary to limited current available tools.
  • The platform is based on AutoDock Vina and caters to users without computational expertise, expanding the scope of proteins a ligand can be tested against.
  • By enabling efficient predictions of ligand-protein interactions, ReverseDock aims to optimize drug screening processes, potentially lowering experimental costs and improving research workflows.
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