keyword
MENU ▼
Read by QxMD icon Read
search

Chaperones

keyword
https://www.readbyqxmd.com/read/29244160/interplay-between-the-catabolite-repression-control-protein-crc-hfq-and-rna-in-hfq-dependent-translational-regulation-in-pseudomonas-aeruginosa
#1
Elisabeth Sonnleitner, Alexander Wulf, Sébastien Campagne, Xue-Yuan Pei, Michael T Wolfinger, Giada Forlani, Konstantin Prindl, Laetitia Abdou, Armin Resch, Frederic H-T Allain, Ben F Luisi, Henning Urlaub, Udo Bläsi
In Pseudomonas aeruginosa the RNA chaperone Hfq and the catabolite repression control protein (Crc) act as post-transcriptional regulators during carbon catabolite repression (CCR). In this regard Crc is required for full-fledged Hfq-mediated translational repression of catabolic genes. RNAseq based transcriptome analyses revealed a significant overlap between the Crc and Hfq regulons, which in conjunction with genetic data supported a concerted action of both proteins. Biochemical and biophysical approaches further suggest that Crc and Hfq form an assembly in the presence of RNAs containing A-rich motifs, and that Crc interacts with both, Hfq and RNA...
December 13, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/29243089/structural-insights-on-the-dynamics-of-proteasome-formation
#2
REVIEW
Koichi Kato, Tadashi Satoh
Molecular organization in biological systems comprises elaborately programmed processes involving metastable complex formation of biomolecules. This is exemplified by the formation of the proteasome, which is one of the largest and most complicated biological supramolecular complexes. This biomolecular machinery comprises approximately 70 subunits, including structurally homologous, but functionally distinct, ones, thereby exerting versatile proteolytic functions. In eukaryotes, proteasome formation is non-autonomous and is assisted by assembly chaperones, which transiently associate with assembly intermediates, operating as molecular matchmakers and checkpoints for the correct assembly of proteasome subunits...
December 14, 2017: Biophysical Reviews
https://www.readbyqxmd.com/read/29242535/lipid-bodies-containing-oxidatively-truncated-lipids-block-antigen-cross-presentation-by-dendritic-cells-in-cancer
#3
Filippo Veglia, Vladimir A Tyurin, Dariush Mohammadyani, Maria Blasi, Elizabeth K Duperret, Laxminarasimha Donthireddy, Ayumi Hashimoto, Alexandr Kapralov, Andrew Amoscato, Roberto Angelini, Sima Patel, Kevin Alicea-Torres, David Weiner, Maureen E Murphy, Judith Klein-Seetharaman, Esteban Celis, Valerian E Kagan, Dmitry I Gabrilovich
Cross-presentation is a critical function of dendritic cells (DCs) required for induction of antitumor immune responses and success of cancer immunotherapy. It is established that tumor-associated DCs are defective in their ability to cross-present antigens. However, the mechanisms driving these defects are still unknown. We find that impaired cross-presentation in DCs is largely associated with defect in trafficking of peptide-MHC class I (pMHC) complexes to the cell surface. DCs in tumor-bearing hosts accumulate lipid bodies (LB) containing electrophilic oxidatively truncated (ox-tr) lipids...
December 14, 2017: Nature Communications
https://www.readbyqxmd.com/read/29242277/endoplasmic-reticulum-chaperone-grp78-regulates-macrophage-function-and-insulin-resistance-in-diet-induced-obesity
#4
Jong Hun Kim, Eunjung Lee, Randall H Friedline, Sujin Suk, Dae Young Jung, Sezin Dagdeviren, Xiaodi Hu, Kunikazu Inashima, Hye Lim Noh, Jung Yeon Kwon, Aya Nambu, Jun R Huh, Myoung Sook Han, Roger J Davis, Amy S Lee, Ki Won Lee, Jason K Kim
Obesity-mediated inflammation is a major cause of insulin resistance, and macrophages play an important role in this process. The 78-kDa glucose-regulated protein (GRP78) is a major endoplasmic reticulum chaperone that modulates unfolded protein response (UPR), and mice with GRP78 heterozygosity were resistant to diet-induced obesity. Here, we show that mice with macrophage-selective ablation of GRP78 (Lyz-GRP78-/-) are protected from skeletal muscle insulin resistance without changes in obesity compared with wild-type mice after 9 wk of high-fat diet...
December 14, 2017: FASEB Journal: Official Publication of the Federation of American Societies for Experimental Biology
https://www.readbyqxmd.com/read/29241555/inhibiting-the-ca2-influx-induced-by-human-csf
#5
Anna Drews, Suman De, Patrick Flagmeier, David C Wirthensohn, Wei-Hsin Chen, Daniel R Whiten, Margarida Rodrigues, Cécile Vincke, Serge Muyldermans, Ross W Paterson, Catherine F Slattery, Nick C Fox, Jonathan M Schott, Henrik Zetterberg, Christopher M Dobson, Sonia Gandhi, David Klenerman
One potential therapeutic strategy for Alzheimer's disease (AD) is to use antibodies that bind to small soluble protein aggregates to reduce their toxic effects. However, these therapies are rarely tested in human CSF before clinical trials because of the lack of sensitive methods that enable the measurement of aggregate-induced toxicity at low concentrations. We have developed highly sensitive single vesicle and single-cell-based assays that detect the Ca2+ influx caused by the CSF of individuals affected with AD and healthy controls, and we have found comparable effects for both types of samples...
December 12, 2017: Cell Reports
https://www.readbyqxmd.com/read/29239106/er-stress-in-skeletal-muscle-remodeling-and-myopathies
#6
REVIEW
Dil Afroze, Ashok Kumar
Skeletal muscle is a highly plastic tissue in the human body that undergoes extensive adaptation in response to environmental cues, such as physical activity, metabolic perturbation, and disease conditions. The endoplasmic reticulum (ER) plays a pivotal role in protein folding and calcium homeostasis in many mammalian cell types including skeletal muscle. However, overload of misfolded or unfolded proteins in the ER lumen cause stress, which results in the activation of a signaling network called the unfolded protein response (UPR)...
December 14, 2017: FEBS Journal
https://www.readbyqxmd.com/read/29239069/the-antiviral-role-of-zinc-and-metallothioneins-in-hepatitis-c-infection
#7
Scott A Read, Grant Parnell, David Booth, Mark W Douglas, Jacob George, Golo Ahlenstiel
Metallothioneins (MTs) are small, cysteine rich proteins characterized by a high affinity for monovalent and divalent cations, such as copper and zinc. Of the four known metallothionein isoforms, only members of the metallothionein 1 and 2 subfamilies are widely expressed, acting as metal chaperones whose primary role is to mediate intracellular zinc homeostasis. Metallothioneins are potently induced by heavy metals and other sources of oxidative stress where they facilitate metal binding and detoxification as well as free radical scavenging...
December 14, 2017: Journal of Viral Hepatitis
https://www.readbyqxmd.com/read/29237842/human-norovirus-ns3-has-rna-helicase-and-chaperoning-activities
#8
Teng-Feng Li, Myra Hosmillo, Hella Schwanke, Ting Shu, Zhaowei Wang, Lei Yin, Stephen Curry, Ian G Goodfellow, Xi Zhou
RNA remodeling proteins, including RNA helicases and chaperones, act to remodel RNA structures and/or protein-RNA interactions, and are required for all processes involving RNAs. Although many viruses encode RNA helicases and chaperones, their in vitro activities and their roles in infected cells largely remain elusive. Noroviruses are a diverse group of positive-stranded RNA viruses in the family Caliciviridae, and constitute a significant and potentially fatal threat to human health. Here we report that protein NS3 encoded by human norovirus has both ATP-dependent RNA helicase activity that unwinds RNA helices and ATP-independent RNA chaperoning activity that can remodel structured RNAs and facilitate strand-annealing...
December 13, 2017: Journal of Virology
https://www.readbyqxmd.com/read/29237836/structure-of-the-paramyxovirus-piv5-nucleoprotein-in-complex-with-an-amino-terminal-peptide-of-the-phosphoprotein
#9
Megha Aggarwal, George P Leser, Christopher A Kors, Robert A Lamb
Parainfluenza virus 5 (PIV5) belongs to the family Paramyxoviridae, which consists of enveloped viruses with a non-segmented negative strand RNA genome encapsidated by the nucleoprotein (N). Paramyxovirus replication is regulated by the phosphoprotein (P) through protein-protein interactions with N and the RNA polymerase (L). The chaperone activity of P is essential to maintain the unassembled RNA-free form of N in order to prevent non-specific RNA binding and premature N oligomerization. Here, we determined the crystal structure of unassembled PIV5 N in complex with a P peptide (N0P) derived from the N-terminus of P (P50) at 2...
December 13, 2017: Journal of Virology
https://www.readbyqxmd.com/read/29235845/structure-based-identification-of-hiv-1-nucleocapsid-protein-inhibitors-active-against-wild-type-and-drug-resistant-hiv-1-strains
#10
Mattia Mori, Lesia Kovalenko, Savina Malancona, Francesco Saladini, Davide De Forni, Manuel Pires, Nicolas Humbert, Eleonore Real, Thomas Botzanowski, Sarah Cianférani, Alessia Giannini, Maria Chiara Dasso Lang, Giulia Cugia, Barbara Poddesu, Franco Lori, Maurizio Zazzi, Steven Harper, Vincenzo Summa, Yves Mély, Maurizio Botta
HIV/AIDS is still one of the leading causes of death worldwide. Current drugs that target the canonical steps of HIV-1 life cycle are efficient in blocking viral replication, but are unable to eradicate HIV-1 from infected patients. Moreover, drug resistance (DR) is often associated with the clinical use of these molecules, thus raising the need for novel drug candidates as well as novel putative drug targets. In this respect, pharmacological inhibition of the highly conserved and multifunctional nucleocapsid protein (NC) of HIV-1 is considered a promising alternative to current drugs, particularly to overcome DR...
December 13, 2017: ACS Chemical Biology
https://www.readbyqxmd.com/read/29235576/the-unfolded-protein-response-impacts-melanoma-progression-by-enhancing-fgf-expression-and-can-be-antagonized-by-a-chemical-chaperone
#11
Karin Eigner, Yüksel Filik, Florian Mark, Birgit Schütz, Günter Klambauer, Richard Moriggl, Markus Hengstschläger, Herbert Stangl, Mario Mikula, Clemens Röhrl
The mechanisms hallmarking melanoma progression are insufficiently understood. Here we studied the impact of the unfolded protein response (UPR) - a signalling cascade playing ambiguous roles in carcinogenesis - in melanoma malignancy. We identified isogenic patient-derived melanoma cell lines harboring BRAFV600E-mutations as a model system to study the role of intrinsic UPR in melanoma progression. We show that the activity of the three effector pathways of the UPR (ATF6, PERK and IRE1) was increased in metastatic compared to non-metastatic cells...
December 13, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29235503/inactivation-of-the-dnak-gene-in-clostridium-difficile-630-%C3%AE-erm-yields-a-temperature-sensitive-phenotype-and-increases-biofilm-forming-ability
#12
Shailesh Jain, Deborah Smyth, Barry M G O'Hagan, John T Heap, Geoff McMullan, Nigel P Minton, Nigel G Ternan
Clostridium difficile infection is a growing problem in healthcare settings worldwide and results in a considerable socioeconomic impact. New hypervirulent strains and acquisition of antibiotic resistance exacerbates pathogenesis; however, the survival strategy of C. difficile in the challenging gut environment still remains incompletely understood. We previously reported that clinically relevant heat-stress (37-41 °C) resulted in a classical heat-stress response with up-regulation of cellular chaperones...
December 13, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29235276/-anti-tumor-target-identification-and-molecular-mechanism-study-of-total-saponins-from-albizia-julibrissin
#13
Yi Qian, Qing-Hua Han, Dan Liu, Peng-Fei Tu, Ke-Wu Zeng, Hong Liang
Dried stem bark from Albizia julibrissin(AJ) is a common traditional Chinese herb with several therapy effects including insomnia, anxiety and anti-tumor. Recently, the anti-tumor effect and mechanism studies of AJ have drawn much attention; however, there are still some troubles in chemical composition separation, which leads to the difficulties in pharmacological research of AJ. In this study, we firstly confirmed the proliferation inhibitory effect of total saponins from AJ(TSAJ)on human hepatocarcinoma(HepG2) cells, and also tested the apoptosis induction effect of TSAJ...
October 2017: Zhongguo Zhong Yao za Zhi, Zhongguo Zhongyao Zazhi, China Journal of Chinese Materia Medica
https://www.readbyqxmd.com/read/29235217/heterologous-protein-expression-in-pichia-pastoris-latest-research-progress-and-applications
#14
REVIEW
Veeresh Juturu, Jin Chuan Wu
Pichia pastoris is a well-known platform strain for heterologous protein expression. Over the past five years, different strategies to improve the efficiency of recombinant protein expression by this yeast strain have been developed; these include a patent-free protein expression kit, construction of the P. pastoris CBS7435Ku70 platform strain with its high efficiency in site-specific recombination of plasmid DNA into the genomic DNA, the design of synthetic promoters and their variants by combining different core promoters with multiple putative transcription factors, the generation of mutant GAP promoter variants with various promoter strengths, codon optimization, engineering the α-factor signal sequence by replacing the native glutamic acid at the Kex2 cleavage site with the other 19 natural amino acids and the addition of mammalian signal sequence to the yeast signal sequence, and the co-expression of single chaperones, multiple chaperones or helper proteins that aid in recombinant protein folding...
December 13, 2017: Chembiochem: a European Journal of Chemical Biology
https://www.readbyqxmd.com/read/29234142/a-molecular-chaperone-activity-of-ccs-restores-the-maturation-of-sod1-fals-mutants
#15
Enrico Luchinat, Letizia Barbieri, Lucia Banci
Superoxide dismutase 1 (SOD1) is an important metalloprotein for cellular oxidative stress defence, that is mutated in familiar variants of Amyotrophic Lateral Sclerosis (fALS). Some mutations destabilize the apo protein, leading to the formation of misfolded, toxic species. The Copper Chaperone for SOD1 (CCS) transiently interacts with SOD1 and promotes its correct maturation by transferring copper and catalyzing disulfide bond formation. By in vitro and in-cell NMR, we investigated the role of the SOD-like domain of CCS (CCS-D2)...
December 12, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29234026/bri2-brichos-client-specificity-and-chaperone-activity-are-governed-by-assembly-state
#16
Gefei Chen, Axel Abelein, Harriet E Nilsson, Axel Leppert, Yuniesky Andrade-Talavera, Simone Tambaro, Lovisa Hemmingsson, Firoz Roshan, Michael Landreh, Henrik Biverstål, Philip J B Koeck, Jenny Presto, Hans Hebert, André Fisahn, Jan Johansson
Protein misfolding and aggregation is increasingly being recognized as a cause of disease. In Alzheimer's disease the amyloid-β peptide (Aβ) misfolds into neurotoxic oligomers and assembles into amyloid fibrils. The Bri2 protein associated with Familial British and Danish dementias contains a BRICHOS domain, which reduces Aβ fibrillization as well as neurotoxicity in vitro and in a Drosophila model, but also rescues proteins from irreversible non-fibrillar aggregation. How these different activities are mediated is not known...
December 12, 2017: Nature Communications
https://www.readbyqxmd.com/read/29233876/molecular-control-of-chaperone-mediated-autophagy
#17
REVIEW
Steve Catarino, Paulo Pereira, Henrique Girão
Chaperone-mediated autophagy (CMA) is a selective form of autophagy in which cytosolic proteins bearing a pentapeptide motif biochemically related to the KFERQ sequence, are recognized by the heat shock protein family A member 8 (HSPA8) chaperone, delivered to the lysomal membrane, and directly translocated across the lysosomal membrane by a protein complex containing lysosomal associated membrane protein 2a (Lamp2a). Since its discovery over two decades ago, the importance of this pathway in cell proteostasis has been made increasingly apparent...
December 12, 2017: Essays in Biochemistry
https://www.readbyqxmd.com/read/29233861/restoration-of-metabolic-inflammation-related-ghrelin-resistance-by-weight-loss
#18
Farhana Naznin, Koji Toshinai, Tm Zaved Waise, Tadashi Okada, Hideyuki Sakoda, Masamitsu Nakazato
High-fat diet (HFD)-induced metabolic inflammation in the central and peripheral organs contributes to the pathogenesis of obesity. Long-term HFD blunts signaling by ghrelin, a gastric-derived orexigenic peptide, in the vagal afferent nerve via a mechanism involving in situ activation of inflammation. This study was undertaken to investigate whether ghrelin resistance is associated with progressive development of metabolic inflammation. In mice, ghrelin's orexigenic activity was abolished 2 to 4 weeks after the commencement of HFD (60% of energy from fat), consistent with the timing of accumulation and activation of macrophages and microglia in the nodose ganglion and hypothalamus...
December 12, 2017: Journal of Molecular Endocrinology
https://www.readbyqxmd.com/read/29232016/characterization-of-h3-3-and-hira-expression-and-function-in-bovine-early-embryos
#19
Kun Zhang, Han Wang, Sandeep K Rajput, Joseph K Folger, George W Smith
Histone variant H3.3 is encoded by two distinct genes, H3F3A and H3F3B, that are closely associated with actively transcribed genes. H3.3 replacement is continuous and essential for maintaining correct chromatin structure during mouse oogenesis. Upon fertilization, H3.3 is incorporated to parental chromatin, and is required for blastocyst formation in mice. The H3.3 exchange process is facilitated by the chaperone HIRA, particularly during zygote development. We previously demonstrated that H3.3 is required for bovine early embryonic development; here, we explored the mechanisms of its functional requirement...
December 12, 2017: Molecular Reproduction and Development
https://www.readbyqxmd.com/read/29229758/the-stress-sigma-factor-of-rna-polymerase-rpos-%C3%AF-s-is-a-solvent-exposed-open-molecule-in-solution
#20
Paola Cavaliere, Sébastien Brier, Petr Filipenko, Christina Sizun, Bertrand Raynal, Françoise Bonneté, Fabienne Levi-Acobas, Jacques Bellalou, Patrick England, Julia Chamot-Rooke, Claudine Mayer, Françoise Norel
In bacteria, one primary and multiple alternative σ factors associate with the RNA polymerase core enzyme (E) to form holoenzymes (Eσ) with different promoter recognition specificities. The alternative σ factor RpoS/σS is produced in stationary phase and under stress conditions and reprograms global gene expression to promote bacterial survival. To date, the three-dimensional structure of a full-length free σ factor remains elusive. The current model suggests that extensive interdomain contacts in a free σ factor result in a compact conformation that masks the DNA-binding determinants of σ, explaining why a free σ factor does not bind double stranded promoter DNA efficiently...
December 11, 2017: Biochemical Journal
keyword
keyword
33199
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"