Read by QxMD icon Read

Bidirectional affinity

Tobias Bethge, Elvis Ajuh, Hans H Hirsch
: Rearrangements or point mutations in the noncoding control region (NCCR) of BK polyomavirus (BKPyV) have been associated with higher viral loads and more pronounced organ pathology in immunocompromised patients. The respective alterations affect a multitude of transcription factor binding sites (TFBS) but consistently cause increased expression of the early viral gene region (EVGR) at the expense of late viral gene region (LVGR) expression. By mutating TFBS, we identified three phenotypic groups leading to strong, intermediate, or impaired EVGR expression and corresponding BKPyV replication...
November 15, 2016: Journal of Virology
Roberto Di Maio, Paul J Barrett, Eric K Hoffman, Caitlyn W Barrett, Alevtina Zharikov, Anupom Borah, Xiaoping Hu, Jennifer McCoy, Charleen T Chu, Edward A Burton, Teresa G Hastings, J Timothy Greenamyre
α-Synuclein accumulation and mitochondrial dysfunction have both been strongly implicated in the pathogenesis of Parkinson's disease (PD), and the two appear to be related. Mitochondrial dysfunction leads to accumulation and oligomerization of α-synuclein, and increased levels of α-synuclein cause mitochondrial impairment, but the basis for this bidirectional interaction remains obscure. We now report that certain posttranslationally modified species of α-synuclein bind with high affinity to the TOM20 (translocase of the outer membrane 20) presequence receptor of the mitochondrial protein import machinery...
June 8, 2016: Science Translational Medicine
Nicholas A Willis, Ralph Scully
The Escherichia coli replication fork arrest complex Tus/Ter mediates site-specific replication fork arrest and homologous recombination (HR) on a mammalian chromosome, inducing both conservative "short tract" gene conversion (STGC) and error-prone "long tract" gene conversion (LTGC) products. We showed previously that bidirectional fork arrest is required for the generation of STGC products at Tus/Ter-stalled replication forks and that the HR mediators BRCA1, BRCA2 and Rad51 mediate STGC but suppress LTGC at Tus/Ter-arrested forks...
July 17, 2016: Cell Cycle
Kyung Ah Han, Doyeon Woo, Seungjoon Kim, Gayoung Choii, Sangmin Jeon, Seoung Youn Won, Ho Min Kim, Won Do Heo, Ji Won Um, Jaewon Ko
UNLABELLED: Neurotrophin-3 (NT-3) is a secreted neurotrophic factor that binds neurotrophin receptor tyrosine kinase C (TrkC), which in turn binds to presynaptic protein tyrosine phosphatase σ (PTPσ) to govern excitatory synapse development. However, whether and how NT-3 cooperates with the TrkC-PTPσ synaptic adhesion pathway and TrkC-mediated intracellular signaling pathways in rat cultured neurons has remained unclear. Here, we report that NT-3 enhances TrkC binding affinity for PTPσ...
April 27, 2016: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Matthias P Mayer, Roman Kityk
Hsp70s chaperone an amazing number and variety of cellular protein folding processes. Key to their versatility is the recognition of a short degenerate sequence motif, present in practically all polypeptides, and a bidirectional allosteric intramolecular regulation mechanism linking their N-terminal nucleotide binding domain (NBD) and their C-terminal polypeptide substrate binding domain (SBD). Through this interdomain communication ATP binding to the NBD and ATP hydrolysis control the affinity of the SBD for polypeptide substrates and substrate binding to the SBD triggers ATP hydrolysis...
2015: Frontiers in Molecular Biosciences
Gerhard Prenner, Domingos Cardoso, Charles E Zartman, Luciano P de Queiroz
PREMISE OF THE STUDY: Floral development can help to shed light on puzzling features across flowering plants. The enigmatic Amazonian monospecific genus Petaladenium of the legume family (Leguminosae) had rarely been collected and only recently became available for ontogenetic studies. The fimbriate-glandular wing petals of P. urceoliferum are unique among the more than 19000 legume species. Ontogenetic data illuminate the systematic position of the genus and foster our understanding on floral evolution during the early diversification of the papilionoid legumes...
November 2015: American Journal of Botany
Shuji Kawamoto, Hideo Hirakata, Naoko Sugita, Kazuhiko Fukuda
Platelets express the imidazoline (I)-receptor, I1 and I2, as well as the α2-adrenoceptor. Although dexmedetomidine, a selective α2-adrenoceptor agonist with some affinity for the I-receptor is expected to affect platelet function, the effects of dexmedetomidine on platelet functions remain unclear. In the present study, we investigated the effects of dexmedetomidine on human platelet functions in vitro. The effects of dexmedetomidine on platelet aggregation were examined using aggregometers. The formation of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) in platelets was measured by an enzyme immunoassay...
November 5, 2015: European Journal of Pharmacology
Lianguo Wang, Nicole M De Jesus, Crystal M Ripplinger
Sarcoplasmic reticulum (SR) Ca2+ handling plays a key role in normal excitation-contraction coupling and aberrant SR Ca2+ handling is known to play a significant role in certain types of arrhythmia. Because arrhythmias are spatially distinct, emergent phenomena, they must be investigated at the tissue level. However, methods for directly probing SR Ca2+ in the intact heart remain limited. This article describes the protocol for dual optical mapping of transmembrane potential (Vm) and free intra-SR [Ca2+] ([Ca2+]SR) in the Langendorff-perfused rabbit heart...
September 10, 2015: Journal of Visualized Experiments: JoVE
Renata Balgley, Sreejith Shankar, Michal Lahav, Milko E van der Boom
We demonstrate how the distance over which electron transfer occurs through organic materials can be controlled and extended. Coating of conductive surfaces with nanoscale layers of redox-active metal complexes allows the electrochemical addressing of distant layers that are otherwise electrochemically silent. Our materials can pass electrons selectively in directions that are determined by positioning of layers of metal complexes and the distances between them. These electron-transfer processes can be made dominantly uni- or bidirectional...
October 12, 2015: Angewandte Chemie
Howard S Hock, Gregor Schöner
Evidence obtained using the dynamic grouping method has shown that the grouping of an object's connected surfaces has properties characteristic of a nonlinear dynamical system. When a surface's luminance changes, one of its boundaries is perceived moving across the surface. The direction of this dynamic grouping (DG) motion indicates which of two flanking surfaces has been grouped with the changing surface. A quantitative measure of overall grouping strength (affinity) for adjacent surfaces is provided by the frequency of DG motion perception in directions promoted by the grouping variables...
September 2016: Vision Research
Daniel V Iwamoto, David A Calderwood
Integrins are heterodimeric transmembrane adhesion receptors that couple the actin cytoskeleton to the extracellular environment and bidirectionally relay signals across the cell membrane. These processes are critical for cell attachment, migration, differentiation, and survival, and therefore play essential roles in metazoan development, physiology, and pathology. Integrin-mediated adhesions are regulated by diverse factors, including the conformation-specific affinities of integrin receptors for their extracellular ligands, the clustering of integrins and their intracellular binding partners into discrete adhesive structures, mechanical forces exerted on the adhesion, and the intracellular trafficking of integrins themselves...
October 2015: Current Opinion in Cell Biology
L Jordaens, M Arias-Alvarez, I Pintelon, S Thys, S Valckx, Y Dezhkam, P E J Bols, J L M R Leroy
Elevated non-esterified fatty acids (NEFAs) have been recognized as an important link between lipolytic metabolic conditions and impaired fertility in high-yielding dairy cows. However, NEFA effects on the oviductal micro-environment currently remain unknown. We hypothesize that elevated NEFAs may contribute to the complex pathology of subfertility by exerting a negative effect on bovine oviductal epithelial cell (BOEC) physiology. Therefore, the objectives of this study were to elucidate direct NEFA effects on BOEC physiology in three different in vitro cell culture systems...
October 1, 2015: Theriogenology
Matthew C Jones, Jonathan D Humphries, Adam Byron, Angélique Millon-Frémillon, Joseph Robertson, Nikki R Paul, Daniel H J Ng, Janet A Askari, Martin J Humphries
The integration of cells with their extracellular environment is facilitated by cell surface adhesion receptors, such as integrins, which play important roles in both normal development and the onset of pathologies. Engagement of integrins with their ligands in the extracellular matrix, or counter-receptors on other cells, initiates the intracellular assembly of a wide variety of proteins into adhesion complexes such as focal contacts, focal adhesions, and fibrillar adhesions. The proteins recruited to these complexes mediate bidirectional signaling across the plasma membrane, and, as such, help to coordinate and/or modulate the multitude of physical and chemical signals to which the cell is subjected...
March 2, 2015: Current Protocols in Cell Biology
Norelle C Wildburger, Syed R Ali, Wei-Chun J Hsu, Alexander S Shavkunov, Miroslav N Nenov, Cheryl F Lichti, Richard D LeDuc, Ekaterina Mostovenko, Neli I Panova-Elektronova, Mark R Emmett, Carol L Nilsson, Fernanda Laezza
Voltage-gated sodium channels (Nav1.1-Nav1.9) are responsible for the initiation and propagation of action potentials in neurons, controlling firing patterns, synaptic transmission and plasticity of the brain circuit. Yet, it is the protein-protein interactions of the macromolecular complex that exert diverse modulatory actions on the channel, dictating its ultimate functional outcome. Despite the fundamental role of Nav channels in the brain, information on its proteome is still lacking. Here we used affinity purification from crude membrane extracts of whole brain followed by quantitative high-resolution mass spectrometry to resolve the identity of Nav1...
May 2015: Molecular & Cellular Proteomics: MCP
Simone Bonetti, Assunta Pistone, Marco Brucale, Saskia Karges, Laura Favaretto, Massimo Zambianchi, Tamara Posati, Anna Sagnella, Marco Caprini, Stefano Toffanin, Roberto Zamboni, Nadia Camaioni, Michele Muccini, Manuela Melucci, Valentina Benfenati
Lysinated molecular organic semiconductors are introduced as valuable multifunctional platforms for neural cells growth and interfacing. Cast films of quaterthiophene (T4) semiconductor covalently modified with lysine-end moieties (T4Lys) are fabricated and their stability, morphology, optical/electrical, and biocompatibility properties are characterized. T4Lys films exhibit fluorescence and electronic transport as generally observed for unsubstituted oligothiophenes combined to humidity-activated ionic conduction promoted by the charged lysine-end moieties...
June 3, 2015: Advanced Healthcare Materials
Vinnie Gaul, Sergio G Lopez, Barry R Lentz, Niamh Moran, Robert J Forster, Tia E Keyes
Platelet integrin αIIbβ3 is a key mediator of platelet activation and thrombosis. Upon activation αIIbβ3 undergoes significant conformational rearrangement, inducing complex bidirectional signalling and protein recruitment leading to platelet activation. Reconstituted lipid models of the integrin can enhance our understanding of the structural and mechanistic details of αIIbβ3 behaviour away from the complexity of the platelet machinery. Here, a novel method of αIIbβ3 insertion into Giant Unilamellar Vesicles (GUVs) is described that allows for effective integrin reconstitution unrestricted by lipid composition...
April 2015: Integrative Biology: Quantitative Biosciences From Nano to Macro
Geng-Yuan Chen, David F J Arginteanu, William O Hancock
The kinesin-2 family motor KIF3A/B works together with dynein to bidirectionally transport intraflagellar particles, melanosomes, and neuronal vesicles. Compared with kinesin-1, kinesin-2 is less processive, and its processivity is more sensitive to load, suggesting that processivity may be controlled by different gating mechanisms. We used stopped-flow and steady-state kinetics experiments, along with single-molecule and multimotor assays to characterize the entire kinetic cycle of a KIF3A homodimer that exhibits motility similar to that of full-length KIF3A/B...
April 17, 2015: Journal of Biological Chemistry
Michele Visentin, Ersin Selcuk Unal, Mitra Najmi, Andras Fiser, Rongbao Zhao, I David Goldman
The proton-coupled folate transporter (PCFT) mediates intestinal folate absorption and transport of folates across the choroid plexus. This study focuses on the role of Tyr residues in PCFT function. The substituted Cys-accessibility method identified four Tyr residues (Y291, Y362, Y315, and Y414) that are accessible to the extracellular compartment; three of these (Y291, Y362, and Y315) are located within or near the folate binding pocket. When the Tyr residues were replaced with Cys or Ala, these mutants showed similar (up to 6-fold) increases in influx Vmax and Kt/Ki for [(3)H]methotrexate and [(3)H]pemetrexed...
April 15, 2015: American Journal of Physiology. Cell Physiology
Inji Park, Hyun-Shik Lee
Eph receptors and their ligands, ephrins, represent the largest group of the receptor tyrosine kinase (RTK) family, and they mediate numerous developmental processes in a variety of organisms. Ephrins are membrane-bound proteins that are mainly divided into two classes: A class ephrins, which are linked to the membrane by a glycosylphosphatidylinositol (GPI) linkage, and B class ephrins, which are transmembrane ligands. Based on their domain structures and affinities for ligand binding, the Eph receptors are also divided into two groups...
January 31, 2015: Molecules and Cells
Nina Grossmann, Ahmet S Vakkasoglu, Sabine Hulpke, Rupert Abele, Rachelle Gaudet, Robert Tampé
The ATP-binding cassette (ABC) transporter associated with antigen processing (TAP) participates in immune surveillance by moving proteasomal products into the endoplasmic reticulum (ER) lumen for major histocompatibility complex class I loading and cell surface presentation to cytotoxic T cells. Here we delineate the mechanistic basis for antigen translocation. Notably, TAP works as a molecular diode, translocating peptide substrates against the gradient in a strict unidirectional way. We reveal the importance of the D-loop at the dimer interface of the two nucleotide-binding domains (NBDs) in coupling substrate translocation with ATP hydrolysis and defining transport vectoriality...
2014: Nature Communications
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"