Search results for "Integrin"
showing 10 items of 286 documents
Production, crystallization and preliminary X-ray analysis of the human integrin alpha1 I domain.
1999
Integrin α1β1 is one of the main collagen receptors in many cell types. A fast large-scale production, purification and crystallization method for the integrin α1 I domain is reported here. The α1 I domain was crystallized using the vapour-diffusion method with a reservoir solution containing a mixture of PEG 4000, sodium acetate, glycerol and Tris–HCl buffer. The crystals beong to the C2 space group, with unit-cell parameters a = 74.5, b = 81.9, c = 37.3 Å, α = γ = 90.0, β = 90.8°. The crystals diffract to 2.0 Å and a 94.2% complete data set to 2.2 Å has been collected from a single crystal with an R merge of 5.8%.
Rôle de l’inflammasome dans les pathologies cardiovasculaires
2011
NOD-like receptors (NLRs) constitute a recently identified family of intracellular pattern recognition receptors which contains more than 20 members in mammals. Some of the NLRs, the NALP subfamily, constituted from 14 members, many of them without actual identified role, form multiproteic complex known as inflammasome, that initiate inflammation by processing inactive pro-caspase-1 to its active form, allowing the cleavage and subsequent activation of pro-IL-1β and pro-IL-18. We review the identified roles of NLRs in pathologies and argue for the role of inflammasome in the development of cardiovascular diseases. The atherogenic cytokines IL-1β and IL-18 are matured in NLRPs inflammasomes.…
Impact of Reactive Oxygen Species on the Expression of Adhesion Molecules in Vivo
2008
Many non-surgical tumor treatments induce reactive oxygen species (ROS) which result in cell damage. This study investigated the impact of ROS induction on the expression of adhesion molecules and whether alpha-tocopherol pre-treatment could have a protective effect. Experimental rat DS-sarcomas were treated with a combination of localized 44 degrees C-hyperthermia, inspiratory hyperoxia and xanthine oxidase which together lead to a pronounced ROS induction. Further animals were pre-treated with alpha-tocopherol. The in vivo expression of E- and N-cadherin, alpha-catenin, integrins alpha v, beta 3 and beta 5 as well as of the integrin dimer alpha v beta 3 was assessed by flow cytometry. The…
Amino acid sequence and homology modeling of obtustatin, a novel non-RGD-containing short disintegrin isolated from the venom of Vipera lebetina obtu…
2003
Disintegrins represent a group of cysteine-rich peptides occurring in Crotalidae and Viperidae snake venoms, and are potent antagonists of several integrin receptors. A novel disintegrin, obtustatin, was isolated from the venom of the Vipera lebetina obtusa viper, and represents the first potent and selective inhibitor of the binding of integrin alpha(1)beta(1) to collagen IV. The primary structure of obtustatin contains 41 amino acids and is the shortest disintegrin described to date. Obtustatin shares the pattern of cysteines of other short disintegrins. However, in contrast to known short disintegrins, the integrin-binding loop of obtustatin is two residues shorter and does not express t…
Integrin α2β1 Mediates Isoform-Specific Activation of p38 and Upregulation of Collagen Gene Transcription by a Mechanism Involving the α2 Cytoplasmic…
1999
Two collagen receptors, integrins alpha1beta1 and alpha2beta1, can regulate distinct functions in cells. Ligation of alpha1beta1, unlike alpha2beta1, has been shown to result in recruitment of Shc and activation of the Ras/ERK pathway. To identify the downstream signaling molecules activated by alpha2beta1 integrin, we have overexpressed wild-type alpha2, or chimeric alpha2 subunit with alpha1 integrin cytoplasmic domain in human osteosarcoma cells (Saos-2) lacking endogenous alpha2beta1. The chimeric alpha2/alpha1 chain formed a functional heterodimer with beta1. In contrast to alpha2/alpha1 chimera, forced expression of alpha2 integrin resulted in upregulation of alpha1 (I) collagen gene …
Cholesterol Dependence of Collagen and Echovirus 1 Trafficking along the Novel alpha2beta1 Integrin Internalization Pathway
2013
We have previously shown that soluble collagen and a human pathogen, echovirus 1 (EV1) cluster α2β1 integrin on the plasma membrane and cause their internalization into cytoplasmic endosomes. Here we show that cholesterol plays a major role not only in the uptake of α2β1 integrin and its ligands but also in the formation of α2 integrin-specific multivesicular bodies (α2-MVBs) and virus infection. EV1 infection and α2β1 integrin internalization were totally halted by low amounts of the cholesterol-aggregating drugs filipin or nystatin. Inhibition of cholesterol synthesis and accumulation of lanosterol after ketoconazole treatment inhibited uptake of collagen, virus and clustered integrin, an…
Cancer Signaling Transcriptome Is Upregulated in Type 2 Diabetes Mellitus
2020
We aimed to explore the differences in the whole transcriptome of peripheral blood mononuclear cells between elderly individuals with and without type 2 diabetes (T2D). We conducted a microarray-based transcriptome analysis of 19 individuals with T2D and 15 without. Differentially expressed genes according to linear models were submitted to the Ingenuity Pathway Analysis system to conduct a functional enrichment analysis. We established that diseases, biological functions, and canonical signaling pathways were significantly associated with T2D patients when their logarithms of Benjamini&ndash
Retinoids as a Perspective in Treatment of Alzheimer’s Disease
2010
<i>Background:</i> In the past, we demonstrated that the disintegrin metalloproteinase ADAM10 has α-secretase activity in vitro and in cultured cells. We also found out that moderate overexpression of this proteinase inhibits Aβ peptide production and prevents the formation of amyloid plaques in an Alzheimer’s disease (AD) mouse model. Moreover, it corrects early hippocampal defects like LTP impairment and increases cortical synaptogenesis. <i>Objective:</i> Upregulation of ADAM10 might be an alternative approach concerning AD therapy. Our current research therefore focuses on substances and/or pathways which regulate ADAM10 gene expression. <i>Methods:</i&g…
Human recombinant vasostatin-1 may interfere with cell-extracellular matrix interactions
2006
Vasostatin-1 (VS-1), the N-terminal fragment derived from the cleavage of chromogranin A (CgA), has been shown to exert several biological activities on several tissues and organs. Recently, it has been reported that human recombinant VS-1 (STA-CGA(1-78)) may alter myocardial contractility in eel, frog., and rat hearts. In this article we have explored if STA-CGA(1-78) can induce intracellular cascades interacting both with adhesion molecules and/or extracellular matrix (ECM), components, that is, involvement of the heat shock protein 90 (HSP90) and the endothelial NOS (eNOS), known to be implicated in signal transduction mechanisms affecting myocardial contractility. We used 3D cultured ad…
Binding Properties and Stability of the Ras-Association Domain of Rap1-GTP Interacting Adapter Molecule (RIAM)
2012
The Rap1-GTP interacting adapter protein (RIAM) is an important protein in Rap1-mediated integrin activation. By binding to both Rap1 GTPase and talin, RIAM recruits talin to the cell membrane, thus facilitating talin-dependent integrin activation. In this article, we studied the role of the RIAM Ras-association (RA) and pleckstrin-homology (PH) domains in the interaction with Rap1. We found that the RA domain was sufficient for GTP-dependent interaction with Rap1B, and the addition of the PH domain did not change the binding affinity. We also detected GTP-independent interaction of Rap1B with the N-terminus of RIAM. In addition, we found that the PH domain stabilized the RA domain both in …