Search results for "MITO"
showing 10 items of 2513 documents
Active Fragments from Pro- and Antiapoptotic BCL-2 Proteins Have Distinct Membrane Behavior Reflecting Their Functional Divergence
2010
International audience; BACKGROUND:The BCL-2 family of proteins includes pro- and antiapoptotic members acting by controlling the permeabilization of mitochondria. Although the association of these proteins with the outer mitochondrial membrane is crucial for their function, little is known about the characteristics of this interaction.METHODOLOGY/PRINCIPAL FINDINGS:Here, we followed a reductionist approach to clarify to what extent membrane-active regions of homologous BCL-2 family proteins contribute to their functional divergence. Using isolated mitochondria as well as model lipid Langmuir monolayers coupled with Brewster Angle Microscopy, we explored systematically and comparatively the…
Fluorescent styrylpyrylium probes for the imaging of mitochondria in live cells
2021
Eight styrylpyrylium tetrafluoroborate salts have been synthesized and fully optically characterized by UV-vis absorption and fluorescence steady-state/time-resolved spectroscopies. The new dyes exhibit strong emission bands with yellow–orange colours, depending on the substituents present in the structure. Notably, the Stokes shift recorded for some of them exceeds 100 nm, a very valuable feature for biological imaging. Four of them have been assayed as biological imaging agents by confocal laser scanning microscopy (CLSM) in the human hepatoma cell line Hep3B. It has been found that all the compounds efficiently stain intracellular structures which have been identified as mitochondria thr…
Distinct effects of atypical 1,4-dihydropyridines on 1-methyl-4-phenylpyridinium-induced toxicity.
2006
Our previous data obtained from in vivo experiments demonstrated high neuroprotective effects of three novel atypical neuronal non-calcium antagonistic 1,4-dihydropyridine (DHP) derivatives cerebrocrast, glutapyrone and tauropyrone. The present studies were carried out in vitro to clarify, at least in part, their mechanism of action in primary culture of cerebellar granule cells by use of 1-methyl-4-phenylpyridinium (MPP+) as a neurotoxic agent which causes dramatic oxidative stress. Cerebrocrast (highly lipophilic, with a classical two-ring structure) dose-dependently (0.01-10.0 microM, EC50 = 13 nM) reduced MPP+-induced cell death. At the same time, the calcium antagonist nimodipine (refe…
Polymeric Oriented Monolayers and Multilayers as Model Surfaces
1985
All living cells are surrounded by a lipid bilayer membrane in which a variety of proteins (e.g., enzymes) are embedded (fluid mosaic model; Figure 1). Phospholipids and cholesterol represent the major part of the lipids of a biomembrane. Figure 2 illustrates the structure of some typical amphiphilic membrane components with hydrophobic alkyl chains and hydrophilic head groups. The amount of protein in biological membranes varies between 40 and 60%(3); however, in highly specialized membranes values between 20% (myelin sheath of nerve axons; electrical isolator) and 75% (mitochondrial inner membrane; enzyme system of the respiratory chain) may occur. Furthermore, the incorporation of protei…
“I nipoti non nati”: la nascita e il fantasma dell’assenza. Riscritture dell’identità come anticipazione narrativa della storia del Novecento – Lebed…
2022
The paper questions the theme of identity and the configuration of historical time starting with two of the most significant authors of contemporary Russian literature, Sergej Lebedev and Marija Stepanova. Sergej Lebedev’s debut novel, The border of oblivion, is entirely based on the elaboration of post- memory, the dynamics of memory and oblivion experienced by the generations that inherit the most traumatic events of the twentieth century, entrusted to one style and a formal work that lead to an unusual icasticity and verbal splendor by probing the darkest recesses of history as the most painful twists of identity and self-recognition and by dwelling on images of shocking plasticity. At t…
Isolation and characterization of a Paracentrotus lividus cDNA encoding a stress-inducible chaperonin
2001
Chaperonins are ubiquitous proteins that facilitate protein folding in an adenosine triphosphate–dependent manner. Here we report the isolation of a sea urchin cDNA (Plhsp60) coding for mitochondrial chaperonin (Cpn60), whose basal expression is further enhanced by heat shock. The described cDNA corresponds to a full-length mRNA encoding a protein of 582 amino acids, the first 32 of which constitute a putative mitochondrial targeting leader sequence. Comparative analysis has demonstrated that this protein is highly conserved in evolution.
Papel de COX-2 en la fisiopatología cardíaca
2015
184 págs., 57 fig. y tablas.
Xrcc2 deficiency sensitizes cells to apoptosis by MNNG and the alkylating anticancer drugs temozolomide, fotemustine and mafosfamide
2006
DNA double-strand breaks (DSBs) are potent killing lesions, and inefficient repair of DSBs does not only lead to cell death but also to genomic instability and tumorigenesis. DSBs are repaired by non-homologous end-joining and homologous recombination (HR). A key player in HR is Xrcc2, a Rad51-like protein. Cells deficient in Xrcc2 are hypersensitive to X-rays and mitomycin C and display increased chromosomal aberration frequencies. In order to elucidate the role of Xrcc2 in resistance to anticancer drugs, we compared Xrcc2 knockout (Xrcc2-/-) mouse embryonic fibroblasts with the corresponding isogenic wild-type and Xrcc2 complemented knockout cells. We show that Xrcc2-/- cells are hypersen…
Apoptosis induced by MNNG in human TK6 lymphoblastoid cells is p53 and Fas/CD95/Apo-1 related.
2003
Agents inducing O(6)-methylguanine (O(6)MeG) in DNA, such as N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), are not only highly mutagenic and carcinogenic but also cytotoxic because of the induction of apoptosis. In CHO fibroblasts, apoptosis triggered by O(6)MeG requires cell proliferation and MutSalpha-dependent mismatch repair and is related to the induction of DNA double-strand breaks (DSBs). Furthermore, it is mediated by Bcl-2 degradation and does not require p53 for which the cells were mutated [Cancer Res. 60 (2000) 5815]. Here we studied cytotoxicity and apoptosis induced by MNNG in a pair of human lymphoblastoid cells expressing wild-type p53 (TK6) and mutant p53 (WTK1) and show tha…
Mitochondrial dynamics in type 2 diabetes: Pathophysiological implications
2017
Mitochondria play a key role in maintaining cellular metabolic homeostasis. These organelles have a high plasticity and are involved in dynamic processes such as mitochondrial fusion and fission, mitophagy and mitochondrial biogenesis. Type 2 diabetes is characterised by mitochondrial dysfunction, high production of reactive oxygen species (ROS) and low levels of ATP. Mitochondrial fusion is modulated by different proteins, including mitofusin-1 (MFN1), mitofusin-2 (MFN2) and optic atrophy (OPA-1), while fission is controlled by mitochondrial fission 1 (FIS1), dynamin-related protein 1 (DRP1) and mitochondrial fission factor (MFF). PARKIN and (PTEN)-induced putative kinase 1 (PINK1) partici…