129 research outputs found
Unc119 Protects from Shigella Infection by Inhibiting the Abl Family Kinases
Bacteria engage cell surface receptors and intracellular signaling molecules to enter the cell. Unc119 is an adaptor protein, which interacts with receptors and tyrosine kinases. Its role in bacterial invasion of cells is unknown.We used biochemical, molecular and cell biology approaches to identify the binding partners of Unc119, and to study the effect of Unc119 on Abl family kinases and Shigella infection. We employed loss-of-function and gain-in-function approaches to study the effect of Unc119 in a mouse model of pulmonary shigellosis. Unc119 interacts with Abl family kinases and inhibits their kinase activity. As a consequence, it inhibits Crk phosphorylation, which is essential for Shigella infection. Unc119 co-localizes with Crk and Shigella in infected cells. Shigella infectivity increases in Unc119-deficient epithelial and macrophage cells. In a mouse model of shigellosis cell-permeable TAT-Unc119 inhibits Shigella infection. Conversely, Unc119 knockdown in vivo results in enhanced bacterial invasion and increased lethality. Unc119 is an inducible protein. Its expression is upregulated by probacteria and bacterial products such as lipopolysacharide and sodium butyrate. The latter inhibits Shigella infection in mouse lungs but is ineffective in Unc119 deficiency.Unc119 inhibits signaling pathways that are used by Shigella to enter the cell. As a consequence it provides partial but significant protection from Shigella infections. Unc119 induction in vivo boosts host defense against infections
Recent development of transient electronics
AbstractTransient electronics are an emerging class of electronics with the unique characteristic to completely dissolve within a programmed period of time. Since no harmful byproducts are released, these electronics can be used in the human body as a diagnostic tool, for instance, or they can be used as environmentally friendly alternatives to existing electronics which disintegrate when exposed to water. Thus, the most crucial aspect of transient electronics is their ability to disintegrate in a practical manner and a review of the literature on this topic is essential for understanding the current capabilities of transient electronics and areas of future research. In the past, only partial dissolution of transient electronics was possible, however, total dissolution has been achieved with a recent discovery that silicon nanomembrane undergoes hydrolysis. The use of single- and multi-layered structures has also been explored as a way to extend the lifetime of the electronics. Analytical models have been developed to study the dissolution of various functional materials as well as the devices constructed from this set of functional materials and these models prove to be useful in the design of the transient electronics
Polymerase Chain Reaction: Applications in Gene and Cell Therapy Studies
The rapidly developing fields of gene and cell therapy allow us a platform to repair or replace defective genes or introduce a missing gene. AAV and lentivirus are common viral vectors used in gene therapy to deliver a DNA payload to a tissue of interest. Recently, self-replicating RNA-based vaccines and therapies are also becoming increasingly popular for gene therapy after the success of SARS-CoV-2 vaccines. Cell therapy is the transplantation of human cells without or with ex vivo modification utilizing CAR-T and stem cell technology. Because PCR allows us to detect transgenes with high sensitivity, we can leverage this technology to quantify the efficacy of a therapy and long-term expression in vivo using both qPCR and RT-qPCR, respectively. PCR provides information that is used to justify first in human dose, toxicological evaluations, efficacy through PK/PD relationships, monitor persistency and shedding as well as biomarker and gene expression quantitation. As evaluation of safety endpoints is critical to drug development, PCR is imperative in the field of clinical pharmacology discovery
A transposon present in specific strains of Bacillus subtilis negatively affects nutrient- and dodecylamine-induced spore germination
Spore germination shows a large inter-strain variability. Spores of certain Bacillus subtilis strains, including isolates from spoiled food products, exhibit different germination behavior from spores of the well-studied model organism Bacillus subtilis 168, often for unknown reasons. In this study, we analyzed spore germination efficiencies and kinetics of seventeen B. subtilis strains with previously sequenced genomes. A subsequent gene-trait matching analysis revealed a correlation between a slow germination phenotype and the presence of a mobile genetic element, i.e. a Tn1546-like transposon. A detailed investigation of the transposon elements showed an essential role of a specific operon (spoVA(2mob) ) in inhibiting spore germination with nutrients and with the cationic surfactant dodecylamine. Our results indicate that this operon negatively influences release of Ca-DPA by the SpoVA channel and may additionally alter earlier germination events, potentially by affecting proteins in the spore inner membrane. The spoVA(2mob) operon is an important factor that contributes to inter-strain differences in spore germination. Screening for its genomic presence can be applied for identification of spores that exhibit specific properties that impede spore eradication by industrial processes. This article is protected by copyright. All rights reserved
PhenoHM: human–mouse comparative phenome–genome server
PhenoHM is a human–mouse comparative phenome–genome server that facilitates cross-species identification of genes associated with orthologous phenotypes (http://phenome.cchmc.org; full open access, login not required). Combining and extrapolating the knowledge about the roles of individual gene functions in the determination of phenotype across multiple organisms improves our understanding of gene function in normal and perturbed states and offers the opportunity to complement biologically the rapidly expanding strategies in comparative genomics. The Mammalian Phenotype Ontology (MPO), a structured vocabulary of phenotype terms that leverages observations encompassing the consequences of mouse gene knockout studies, is a principal component of mouse phenotype knowledge source. On the other hand, the Unified Medical Language System (UMLS) is a composite collection of various human-centered biomedical terminologies. In the present study, we mapped terms reciprocally from the MPO to human disease concepts such as clinical findings from the UMLS and clinical phenotypes from the Online Mendelian Inheritance in Man knowledgebase. By cross-mapping mouse–human phenotype terms, extracting implicated genes and extrapolating phenotype-gene associations between species PhenoHM provides a resource that enables rapid identification of genes that trigger similar outcomes in human and mouse and facilitates identification of potentially novel disease causal genes. The PhenoHM server can be accessed freely at http://phenome.cchmc.org
TbUNC119 and Its Binding Protein Complex Are Essential for Propagation, Motility, and Morphogenesis of Trypanosoma brucei Procyclic Form Cells
Flagellum-mediated motility of Trypanosoma brucei is considered to be essential for the parasite to complete stage development in the tsetse fly vector, while the mechanism by which flagellum-mediated motility is controlled are not fully understood. We thus compared T. brucei whole gene products (amino acid sequence) with Caenorhabditis elegans UNC (uncoordinated) proteins, in order to find uncharacterized motility-related T. brucei genes. Through in silico analysis, we found 88 gene products which were highly similar to C. elegans UNC proteins and categorized them as TbCEUN (T. brucei gene products which have high similarity to C. elegans UNC proteins). Approximately two thirds of the 88 TbCEUN gene products were kinesin-related molecules. A gene product highly similar to C. elegans UNC119 protein was designated as TbUNC119. RNAi-mediated depletion of TbUNC119 showed no apparent phenotype. However, knock-down analysis of both TbUNC119 and its binding protein (TbUNC119BP) which was found by yeast two-hybrid analysis showed characteristic phenotypes, including reduced motility, morphological change (extended cell shape), and cellular apoptosis. Based on the observed phenotypes, possible function of the TbUNC119 and TbUNC119BP is discussed
Role of SpoVA Proteins in Release of Dipicolinic Acid during Germination of Bacillus subtilis Spores Triggered by Dodecylamine or Lysozyme
The release of dipicolinic acid (DPA) during the germination of Bacillus subtilis spores by the cationic surfactant dodecylamine exhibited a pH optimum of ∼9 and a temperature optimum of 60°C. DPA release during dodecylamine germination of B. subtilis spores with fourfold-elevated levels of the SpoVA proteins that have been suggested to be involved in the release of DPA during nutrient germination was about fourfold faster than DPA release during dodecylamine germination of wild-type spores and was inhibited by HgCl(2). Spores carrying temperature-sensitive mutants in the spoVA operon were also temperature sensitive in DPA release during dodecylamine germination as well as in lysozyme germination of decoated spores. In addition to DPA, dodecylamine triggered the release of amounts of Ca(2+) almost equivalent to those of DPA, and at least one other abundant spore small molecule, glutamic acid, was released in parallel with Ca(2+) and DPA. These data indicate that (i) dodecylamine triggers spore germination by opening a channel in the inner membrane for Ca(2+)-DPA and other small molecules, (ii) this channel is composed at least in part of proteins, and (iii) SpoVA proteins are involved in the release of Ca(2+)-DPA and other small molecules during spore germination, perhaps by being a part of a channel in the spore's inner membrane
- …