Search results for "BP"

Closed-Locked and Apo-Resting State Structures of the Human α7 Nicotinic Receptor: A Computational Study

2018

International audience; Nicotinic acetylcholine receptors, belonging to the Cys-loop super-family of ligand-gated ion channels (LGICs), are membrane proteins present in neurons and at neuromuscular junctions. They are responsible for signal transmission, and their function is regulated by neurotransmitters, agonists and antagonists drugs. A detailed knowledge of their conformational transition in response to ligand binding is critical to understand the basis of ligand-receptor interaction, in view of new pharmacological approaches to control receptor activity. However, the scarcity of experimentally derived structures of human channels makes this perspective extremely challenging. To contri…

A possible desensitized state conformation of the human α7 nicotinic receptor: A molecular dynamics study

2017

International audience; The determination of the conformational states corresponding to diverse functional roles of ligand gated ion channels is subject of intense investigation with various techniques, from X-rays structure determination to electrophysiology and computational modeling. Even with a certain number of structures becoming recently available, only few major structural features distinguishing conductive open channel from the non conductive resting protein have been highlighted, while high-resolution details are still missing. The characterization of the desensitized conformation(s) is even more complex, and only few specific characteristics have been identified. Furthermore, exp…

Complex Destabilization in the Mitochondrial Chaperonin Hsp60 Leads to Disease.

2020

Several neurological disorders have been linked to mutations in chaperonin genes and more specifically to the HSPD1 gene. In humans, HSPD1 encodes for the mitochondrial Heat Shock Protein 60 (mtHsp60) chaperonin, which carries out essential protein refolding reactions that help maintain mitochondrial and cellular homeostasis. It functions as a macromolecular complex that provides client proteins an environment that favors proper folding in an ATP dependent manner. It has been established that mtHsp60 plays a crucial role in the proper folding of mitochondrial proteins involved in ATP producing pathways. Recently, various single-point mutations in the mtHsp60 encoding gene have been directly…

Human Mesenchymal Stem Cells Prevent Neurological Complications of Radiotherapy

2019

Radiotherapy is a highly effective tool for the treatment of brain cancer. However, radiation also causes detrimental effects in the healthy tissue, leading to neurocognitive sequelae that compromise the quality of life of brain cancer patients. Despite the recognition of this serious complication, no satisfactory solutions exist at present. Here we investigated the effects of intranasal administration of human mesenchymal stem cells (hMSCs) as a neuroprotective strategy for cranial radiation in mice. Our results demonstrated that intranasally delivered hMSCs promote radiation-induced brain injury repair, improving neurological function. This intervention confers protection against inflamma…

FRET-based dynamic structural biology: Challenges, perspectives and an appeal for open-science practices.

2021

International audience; Single-molecule FRET (smFRET) has become a mainstream technique for studying biomolecular structural dynamics. The rapid and wide adoption of smFRET experiments by an ever- increasing number of groups has generated significant progress in sample preparation, measurement procedures, data analysis, algorithms and documentation. Several labs that employ smFRET approaches have joined forces to inform the smFRET community about streamlining how to perform experiments and analyze results for obtaining quantitative information on biomolecular structure and dynamics. The recent efforts include blind tests to assess the accuracy and the precision of smFRET experiments among d…

2018

During early development the structure and function of the cerebral cortex is critically organized by subplate neurons (SPNs), a mostly transient population of glutamatergic and GABAergic neurons located below the cortical plate. At the molecular and morphological level SPNs represent a rather diverse population of cells expressing a variety of genetic markers and revealing different axonal-dendritic morphologies. Electrophysiologically SPNs are characterized by their rather mature intrinsic membrane properties and firing patterns. They are connected via electrical and chemical synapses to local and remote neurons, e.g., thalamic relay neurons forming the first thalamocortical input to the …

Cryptotanshinone deregulates unfolded protein response and eukaryotic initiation factor signaling in acute lymphoblastic leukemia cells.

2015

Abstract Background: Unfolded protein responses (UPR) determine cell fate and are recognized as anticancer targets. In a previous research, we reported that cryptotanshinone (CPT) exerted cytotoxic effects toward acute lymphoblastic leukemia cells through mitochondria-mediated apoptosis. Purpose: In the present study, we further investigated the role of UPR in CPT-induced cytotoxicity on acute lymphoblastic leukemia cells by applying tools of pharmacogenomics and bioinformatics. Methods: Gene expression profiling was performed by mRNA microarray hybridization. Potential transcription factor binding motifs were identified in the promoter regions of the deregulated genes by Cistrome software.…

Extracellular Vesicle‐Associated RNA as a Carrier of Epigenetic Information

2017

Post-transcriptional regulation of messenger RNA (mRNA) metabolism and subcellular localization is of the utmost importance both during development and in cell differentiation. Besides carrying genetic information, mRNAs contain cis-acting signals (zip codes), usually present in their 5'- and 3'-untranslated regions (UTRs). By binding to these signals, trans-acting factors, such as RNA-binding proteins (RBPs), and/or non-coding RNAs (ncRNAs), control mRNA localization, translation and stability. RBPs can also form complexes with non-coding RNAs of different sizes. The release of extracellular vesicles (EVs) is a conserved process that allows both normal and cancer cells to horizontally tran…

FROM EPIGENETICS TO ANTI-DOPING APPLICATION: A NEW TOOL OF DETECTION

2017

Eukaryotic genomes transcribe up to 90% of the genomic DNA but only 1–2% of these transcripts encode for proteins, whereas the vast majority are transcribed as non-coding RNAs (ncRNAs). They are divided into short ncRNA, particularly microRNA (miRNA) and small interference RNA (siRNA), and long ncRNAs. Noteworthy, they are unexpectedly stable since they are protected from degradation through different mechanisms: package in exosomes/microvesicles structures, in apoptotic bodies, in HDL lipoprotein, or by RNA binding proteins. For several years already, biomarkers have been used to detect biological disease; in the last years, a requirement appeared to find some of them to unearth the signs …

The Unsolved Conundrum of Optimal Blood Pressure Target During Acute Haemorrhagic Stroke: A Comprehensive Analysis

2019

Intracerebral haemorrhage (ICH) is a devastating cerebrovascular disease, which accounts to 15% of all strokes. Among modifiable risk factors for ICH, hypertension is the most frequent. High blood pressure (BP) is detected in more than 75–80% of patients with ICH. Extremely elevated BP has been associated with early hematoma growth, a relatively frequent occur-rence and powerful predictor of poor outcome in patients with spontaneous ICH. On the other hand, excessively low BP might cause cerebral hypoperfusion and ultimately lead to poor outcome. This review will analyse the most important trials that have tried to establish how far should BP be lowered during acute ICH. These trials have de…