Search results for "Motif"
showing 10 items of 290 documents
Nimrod, a Putative Phagocytosis Receptor with EGF Repeats in Drosophila Plasmatocytes
2007
SummaryThe hemocytes, the blood cells of Drosophila, participate in the humoral and cellular immune defense reactions against microbes and parasites [1–8]. The plasmatocytes, one class of hemocytes, are phagocytically active and play an important role in immunity and development by removing microorganisms as well as apoptotic cells. On the surface of circulating and sessile plasmatocytes, we have now identified a protein, Nimrod C1 (NimC1), which is involved in the phagocytosis of bacteria. Suppression of NimC1 expression in plasmatocytes inhibited the phagocytosis of Staphylococcus aureus. Conversely, overexpression of NimC1 in S2 cells stimulated the phagocytosis of both S. aureus and Esc…
Putative identification of an amphipathic alpha-helical sequence in hemolysin of Escherichia coli (HlyA) involved in transmembrane pore formation.
2008
Abstract Escherichia coli hemolysin is a pore-forming protein belonging to the RTX toxin family. Cysteine scanning mutagenesis was performed to characterize the putative pore-forming domain of the molecule. A single cysteine residue was introduced at 48 positions within the sequence spanning residues 170–400 and labeled with the polarity-sensitive dye badan. Spectrofluorimetric analyses indicated that several amino acids in this domain are inserted into the lipid bilayer during pore formation. An amphipathic α-helix spanning residues 272–298 was identified that may line the aqueous pore. The importance of this sequence was highlighted by the introduction of two prolines at positions 284 and…
Crystal structures of three ortho-substituted N-acylhydrazone derivatives
2017
To explore the effect of the nature of substitutions on the structural parameters and hydrogen-bond interactions inN-acylhydrazone derivatives, the crystal structures of threeortho-substitutedN-acylhydrazone derivatives, namely (E)-N-{2-[2-(2-chlorobenzylidene)hydrazinyl]-2-oxoethyl}-4-methylbenzenesulfonamide, C16H16ClN3O3S (I), (E)-N-{2-[2-(2-methylbenzylidene)hydrazinyl]-2-oxoethyl}-4-methylbenzenesulfonamide, C17H19N3O3S (II), and (E)-N-{2-[2-(2-nitrobenzylidene)hydrazinyl]-2-oxoethyl}-4-methylbenzenesulfonamide, C16H16N4O5S (III), have been determined. The structures of the three compounds display similar molecular conformations and hydrogen-bond patterns. The hydrazone part of the mol…
The Mitochondrial Targeting Chaperone 14-3-3ε Regulates a RIG-I Translocon that Mediates Membrane Association and Innate Antiviral Immunity
2012
SummaryRIG-I is a cytosolic pathogen recognition receptor that initiates immune responses against RNA viruses. Upon viral RNA recognition, antiviral signaling requires RIG-I redistribution from the cytosol to membranes where it binds the adaptor protein, MAVS. Here we identify the mitochondrial targeting chaperone protein, 14-3-3ε, as a RIG-I-binding partner and essential component of a translocation complex or “translocon” containing RIG-I, 14-3-3ε, and the TRIM25 ubiquitin ligase. The RIG-I translocon directs RIG-I redistribution from the cytosol to membranes where it mediates MAVS-dependent innate immune signaling during acute RNA virus infection. 14-3-3ε is essential for the stable inte…
Asymmetric Comparison and Querying of Biological Networks
2011
Comparing and querying the protein-protein interaction (PPI) networks of different organisms is important to infer knowledge about conservation across species. Known methods that perform these tasks operate symmetrically, i.e., they do not assign a distinct role to the input PPI networks. However, in most cases, the input networks are indeed distinguishable on the basis of how the corresponding organism is biologically well characterized. In this paper a new idea is developed, that is, to exploit differences in the characterization of organisms at hand in order to devise methods for comparing their PPI networks. We use the PPI network (called Master) of the best characterized organism as a …
Extracting string motif bases for quorum higher than two
2012
Bases of generators of motifs consisting of strings in which some positions can be occupied by a don’t care provide a useful conceptual tool for their description and a way to reduce the time and space involved in the discovery process. In the last few years, a few algorithms have been proposed for the extraction of a basis, building in large part on combinatorial properties of strings and their autocorrelations. Currently, the most efficient techniques for binary alphabets and quorum q = 2 require time quadratic in the length of the host string. The present paper explores properties of motif bases for quorum q ≥ 2, both with binary and general alphabets, by also showing that important resu…
Dimerization of visinin-like protein 1 is regulated by oxidative stress and calcium and is a pathological hallmark of amyotrophic lateral sclerosis
2014
AbstractRedox control of proteins that form disulfide bonds upon oxidative challenge is an emerging topic in the physiological and pathophysiological regulation of protein function. We have investigated the role of the neuronal calcium sensor protein visinin-like protein 1 (VILIP-1) as a novel redox sensor in a cellular system. We have found oxidative stress to trigger dimerization of VILIP-1 within a cellular environment and identified thioredoxin reductase as responsible for facilitating the remonomerization of the dimeric protein. Dimerization is modulated by calcium and not dependent on the myristoylation of VILIP-1. Furthermore, we show by site-directed mutagenesis that dimerization is…
Australia: An Inescapable Cultural Paradigm? Cross- and Transcultural Elements in Tim Winton’s Fiction
2016
The article considers Tim Winton’s fiction in terms of its cross- and transcultural character. Despite the fact that local Australian settings permeate the writer’s narratives, Winton creates an imaginary space that is both local and transnational in terms of its quality of the domestic culture, which Winton extends beyond its original field of practice. Winton achieves the transcultural quality of his fiction through transgressions and boundary breaking that are possible due to his frequent reworking of the traditional Australian themes and concepts of the unknown, supernatural, mystical, numinous and sacred, exploitation of leitmotifs of journey, transit and in-betweenness, use of cross-c…
Recombinant mussel protein Pvfp5β enhances cell adhesion of poly(vinyl alcohol)/k-carrageenan hydrogel scaffolds
2022
Polymeric hydrogels are increasingly considered as scaffolds for tissue engineering due to their extraordinary resemblance with the extracellular matrix (ECM) of many tissues. As cell adhesion is a key factor in regulating important cell functions, hydrogel scaffolds are often functionalized or loaded with a variety of bioactive molecules that can promote adhesion. Interesting biomimetic approaches exploit the properties of mussel-inspired recombinant adhesive proteins. In this work, we prepared hydrogel scaffolds with a 50%w mixture of k-carrageenan (kC) and polyvinyl alcohol (PVA), by a two-step physical gelation process, and we coated them with Perna viridis foot protein-5 beta (Pvfp5 be…
Synthetic retinoids dissociate coactivator binding from corepressor release.
2002
The ligand-activated retinoid receptors RXR and RAR control development, homeostasis and disease by regulating transcription of retinoic acid (RA) responsive target genes or crosstalk with other signalling pathways. According to the current model ligand-binding triggers an exchange between corepressor- and coactivator-complexes that inhibit or potentiate transcription by deacetylating and acetylating nucleosomal histones, respectively. Additional cofactors may modify the transcriptional regulatory process by linking liganded retinoid receptors to structural components of chromatin or protein degradation. The desire to specifically influence defined events in RA-signalling, while others are …