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Eri Uemura, Tatsuya Niwa, Shintaro Minami, Kazuhiro Takemoto, Satoshi Fukuchi, Kodai Machida, Hiroaki Imataka, Takuya Ueda, Motonori Ota, Hideki Taguchi
A subset of the proteome is prone to aggregate formation, which is prevented by chaperones in the cell. To investigate whether the basic principle underlying the aggregation process is common in prokaryotes and eukaryotes, we conducted a large-scale aggregation analysis of ~500 cytosolic budding yeast proteins using a chaperone-free reconstituted translation system, and compared the obtained data with that of ~3,000 Escherichia coli proteins reported previously. Although the physicochemical properties affecting the aggregation propensity were generally similar in yeast and E...
January 12, 2018: Scientific Reports
Joachim Berger, Silke Berger, Mei Li, Arie S Jacoby, Anders Arner, Navid Bavi, Alastair G Stewart, Peter D Currie
The TCP-1 ring complex (TRiC) is a multi-subunit group II chaperonin that assists nascent or misfolded proteins to attain their native conformation in an ATP-dependent manner. Functional studies in yeast have suggested that TRiC is an essential and generalized component of the protein-folding machinery of eukaryotic cells. However, TRiC's involvement in specific cellular processes within multicellular organisms is largely unknown because little validation of TRiC function exists in animals. Our in vivo analysis reveals a surprisingly specific role of TRiC in the biogenesis of skeletal muscle α-actin during sarcomere assembly in myofibers...
January 9, 2018: Cell Reports
Shuai Wei, Ramachandran Chelliah, Byung-Jae Park, Joong-Hyun Park, Fereidoun Forghani, Youn-Seo Park, Min-Seok Cho, Dong-Suk Park, Deog-Hwan Oh
The aim of the study was to identify and evaluate specific biomarkers to differentiate within Bacillus cereus group species from contaminated food samples with the use of real-time PCR. A total of 120 strains, comprising of 28 reference, 2 type, 78 wild strains of B. cereus and B. thuringiensis along with 12 strains representing 2 bacterial groups - B. mycoides, B. pseudomycoides, B. weihenstephanensis (B. cereus group); B. amyloliquefaciens, B. subtilis, Enterococcus faecalis, Escherichia coli, Listeria monocytogenes, Micrococcus luteus, Salmonella enterica, Staphylococcus aureus, Streptococcus pyogenes (non-Bacillus sp...
January 3, 2018: Microbial Pathogenesis
Xiaoqiang Wang, Han Chen, Xinwei Lu, Haixia Chi, Shixin Li, Fang Huang
Proper translocation, membrane insertion and folding are crucial biophysical steps in the biogenesis of functional transmembrane peptides/proteins (TMPs). ATP-dependent chaperonins are able to regulate each of these processes, but the underlying mechanisms remain unclear. In this work, interaction between the bacterial chaperonin GroEL and a synthetic fluorescent transmembrane peptide was investigated by fluorescence anisotropy. Binding of the peptide with GroEL resulted in increased fluorescence anisotropy and intensity...
December 29, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
Ana C Carr, Amr S Khaled, Rania Bassiouni, Orielyz Flores, Daniel Nierenberg, Hammad Bhatti, Priya Vishnubhotla, J Perez Manuel, Santimukul Santra, Annette R Khaled
Identifying new druggable targets is desired to meet the needs for effective cancer treatments. To this end, we previously reported the efficacy of a therapeutic peptide called CT20p that displays selective cytotoxicity through inhibition of a multi-subunit, protein-folding complex called Chaperonin-Containing TCP-1 (CCT). To investigate the role of CCT in cancer progression, we examined protein levels of CCT subunits in liver, prostate, and lung cancer using human tissue microarrays. We found that these cancers expressed higher levels of CCT2 as compared to normal tissues...
December 15, 2017: Oncotarget
Yi Yuan, Chong Du, Cuiji Sun, Jin Zhu, Shan Wu, Yinlong Zhang, Tianjiao Ji, Jianlin Lei, Yinmo Yang, Ning Gao, Guangjun Nie
The targeted delivery of hydrophobic therapeutic drugs to tumors is one of the major challenges in drug development. The use of natural proteins as drug delivery vehicles holds great promise due to various functionalities of proteins. In the current study, we exploited a natural protein, GroEL, which possesses a double layer cage structure, as a hydrophobic drug container, which is switchable by ATP binding to a hydrophilic status, to design a novel and intelligent hydrophobic drug delivery molecular machine with a controlled drug release profile...
December 29, 2017: Nano Letters
Mohamed Lamine Hafirassou, Laurent Meertens, Claudia Umaña-Diaz, Athena Labeau, Ophelie Dejarnac, Lucie Bonnet-Madin, Beate M Kümmerer, Constance Delaugerre, Philippe Roingeard, Pierre-Olivier Vidalain, Ali Amara
Dengue virus (DENV) infections cause the most prevalent mosquito-borne viral disease worldwide, for which no therapies are available. DENV encodes seven non-structural (NS) proteins that co-assemble and recruit poorly characterized host factors to form the DENV replication complex essential for viral infection. Here, we provide a global proteomic analysis of the human host factors that interact with the DENV NS1 protein. Combined with a functional RNAi screen, this study reveals a comprehensive network of host cellular processes involved in DENV infection and identifies DENV host restriction and dependency factors...
December 26, 2017: Cell Reports
Deborah K Shoemark, Richard B Sessions, Andrea Brancaccio, Maria Giulia Bigotti
Class II chaperonins are essential multisubunit complexes that aid the folding of nonnative proteins in the cytosol of archaea and eukarya. They use energy derived from ATP to drive a series of structural rearrangements that enable polypeptides to fold within their central cavity. These events are regulated by an elaborate allosteric mechanism in need of elucidation. We employed mutagenesis and experimental analysis in concert with in silico molecular dynamics simulations and interface-binding energy calculations to investigate the class II chaperonin from Thermoplasma acidophilum Here we describe the effects on the asymmetric allosteric mechanism and on hetero-oligomeric complex formation in a panel of mutants in the ATP-binding pocket of the α and β subunits...
December 12, 2017: FASEB Journal: Official Publication of the Federation of American Societies for Experimental Biology
H Aigner, R H Wilson, A Bracher, L Calisse, J Y Bhat, F U Hartl, M Hayer-Hartl
Plant RuBisCo, a complex of eight large and eight small subunits, catalyzes the fixation of CO2 in photosynthesis. The low catalytic efficiency of RuBisCo provides strong motivation to reengineer the enzyme with the goal of increasing crop yields. However, genetic manipulation has been hampered by the failure to express plant RuBisCo in a bacterial host. We achieved the functional expression of Arabidopsis thaliana RuBisCo in Escherichia coli by coexpressing multiple chloroplast chaperones. These include the chaperonins Cpn60/Cpn20, RuBisCo accumulation factors 1 and 2, RbcX, and bundle-sheath defective-2 (BSD2)...
December 8, 2017: Science
Tomohiro Mizobata, Yasushi Kawata
The bacterial chaperonins are highly sophisticated molecular nanomachines, controlled by the hydrolysis of ATP to dynamically trap and remove from the environment unstable protein molecules that are susceptible to denaturation and aggregation. Chaperonins also act to assist in the refolding of these unstable proteins, providing a means by which these proteins may return in active form to the complex environment of the cell. The Escherichia coli GroE chaperonin system is one of the largest protein supramolecular complexes known, whose quaternary structure is required for segregating aggregation-prone proteins...
November 27, 2017: Biophysical Reviews
Francesco Cappello, Everly Conway de Macario, Francesca Rappa, Giovanni Zummo, Alberto J L Macario
Hsp60 (also called Cpn60) is a chaperonin with essential functions for cell physiology and survival. Additionally, its involvement in the pathogenesis of a variety of diseases (e.g., some autoimmune disorders and cancer) is becoming evident with new research. For example, the distribution and levels of Hsp60 in cells and tissues have been found altered in many pathologic conditions, and the significance of these alterations is being investigated in a number of laboratories. The aim of this ongoing research is to determine the meaning of these Hsp60 alterations with regard to pathogenetic mechanisms, diagnosis, classification of lesions, and assessing prognosis and response to treatment...
2018: Methods in Molecular Biology
Eman Elagamey, Kanika Narula, Arunima Sinha, Sudip Ghosh, Magdi A E Abdellatef, Niranjan Chakraborty, Subhra Chakraborty
Extracellular matrix (ECM) is the unique organelle that perceives stress signals and reprograms molecular events of host cell during patho-stress. However, our understanding of how ECM dictates plant immunity is largely unknown. Vascular wilt caused by the soil borne filamentous fungus Fusarium oxysporum is a major impediment for global crop productivity. To elucidate the role of ECM proteins and molecular mechanism associated with cell wall mediated immunity, the temporal changes of ECM proteome was studied in vascular wilt resistant chickpea cultivar upon F...
November 16, 2017: Proteomics
Jenna T Counts, Tasha M Hester, Labib Rouhana
Chaperonin-containing Tail-less complex polypeptide 1 (CCT) is a highly conserved, hetero-oligomeric complex that ensures proper folding of actin, tubulin, and regulators of mitosis. Eight subunits (CCT1-8) make up this complex, and every subunit has a homolog expressed in the testes and somatic tissue of the planarian flatworm Schmidtea mediterranea. Gene duplications of four subunits in the genomes of S. mediterranea and other planarian flatworms created paralogs to CCT1, CCT3, CCT4, and CCT8 that are expressed exclusively in the testes...
November 2, 2017: Molecular Reproduction and Development
Keiko Kashiwagi, Yusuke Terui, Kazuei Igarashi
Polyamines exist mainly as RNA-polyamine complexes in cells. Thus, we looked for proteins whose synthesis is enhanced by polyamines at the level of translation in mammalian cells. Here, we describe how synthesis of Cct2 (T-complex protein 1, β-subunit, a chaperonin assisting in the folding actin, tubulin, and several other proteins) and eEF1A (one of the elongation factors of protein synthesis) is stimulated by polyamines at the level of translation. Polyamines stimulated Cct2 synthesis through the stimulation of ribosome shunting during 5'-processive scanning of 40S ribosomal subunits from the m(7)G-cap to the initiation codon AUG, and eEF1A synthesis through the structural change of the unusual position of a complementary sequence to 18S rRNA in eEF1A mRNA...
2018: Methods in Molecular Biology
Boudhayan Bandyopadhyay, Adi Goldenzweig, Tamar Unger, Orit Adato, Sarel J Fleishman, Ron Unger, Amnon Horovitz
The GroE chaperonin system in Escherichia coli comprises GroEL and GroES and facilitates ATP-dependent protein folding in vivo and in vitro. Proteins with very similar sequences and structures can differ in their dependence on GroEL for efficient folding. One potential but unverified source for GroEL dependence is frustration, wherein not all interactions in the native state are optimized energetically, thereby potentiating slow folding and misfolding. Here, we chose enhanced green fluorescent protein (eGFP) as a model system and subjected it to random mutagenesis, followed by screening for variants whose in vivo folding displays increased or decreased GroEL dependence...
October 24, 2017: Journal of Biological Chemistry
Toshio Takenaka, Takashi Nakamura, Saeko Yanaka, Maho Yagi-Utsumi, Mahesh S Chandak, Kazunobu Takahashi, Subhankar Paul, Koki Makabe, Munehito Arai, Koichi Kato, Kunihiro Kuwajima
We studied the interaction between GroES and a single-ring mutant (SR1) of GroEL by the NMR titration of 15N-labeled GroES with SR1 at three different temperatures (20, 25 and 30°C) in the presence of 3 mM ADP in 100 mM KCl and 10 mM MgCl2 at pH 7.5. We used SR1 instead of wild-type double-ring GroEL to precisely control the stoichiometry of the GroES binding to be 1:1 ([SR1]:[GroES]). Native heptameric GroES was very flexible, showing well resolved cross peaks of the residues in a mobile loop segment (residue 17-34) and at the top of a roof hairpin (Asn51) in the heteronuclear single quantum coherence spectra...
2017: PloS One
S Peng, Z Chu, J Lu, D Li, Y Wang, S Yang, Y Zhang
Aminoglycoside antibiotics affect protein translation fidelity and lead to protein aggregation and an increase in intracellular oxidative stress level as well. The overexpression of the chaperonin GroEL/GroES system promotes short-term tolerance to aminoglycosides in Escherichia coli. Here, we demonstrated that the coexpression of prefoldin or Hsp60 originating from the hyperthermophilic archaeon Pyrococcus furiosus in E. coli cells can rescue cell growth and inhibit protein aggregation induced by streptomycin exposure...
October 2017: Biochemistry. Biokhimii︠a︡
Young Jun An, Sara E Rowland, Jung-Hyun Na, Dario Spigolon, Seung Kon Hong, Yeo Joon Yoon, Jung-Hyun Lee, Frank T Robb, Sun-Shin Cha
The chaperonins (CPNs) are megadalton sized hollow complexes with two cavities that open and close to encapsulate non-native proteins. CPNs are assigned to two sequence-related groups that have distinct allosteric mechanisms. In Group I CPNs a detachable co-chaperone, GroES, closes the chambers whereas in Group II a built-in lid closes the chambers. Group I CPNs have a bacterial ancestry, whereas Group II CPNs are archaeal in origin. Here we describe open and closed crystal structures representing a new phylogenetic branch of CPNs...
October 10, 2017: Nature Communications
Claudia Sangiorgi, Davide Vallese, Isabella Gnemmi, Fabio Bucchieri, Bruno Balbi, Paola Brun, Angelo Leone, Andrea Giordano, Everly Conway de Macario, Alberto Jl Macario, Francesco Cappello, Antonino Di Stefano
HSP60 has been implicated in chronic inflammatory disease pathogenesis, including chronic obstructive pulmonary disease (COPD), but the mechanisms by which this chaperonin would act are poorly understood. A number of studies suggest a role for extracellular HSP60, since it can be secreted from cells and bind Toll-like receptors; however, the effects of this stimulation have never been extensively studied. We investigated the effects (pro- or anti-inflammatory) of HSP60 in human bronchial epithelial cells (16-HBE) alone and in comparison with oxidative, inflammatory, or bacterial challenges...
October 1, 2017: International Journal of Immunopathology and Pharmacology
Xuejun Zhao, Jiangfan Xiu, Yan Li, Huiling Ma, Jianwei Wu, Bo Wang, Guo Guo
Chaperonins, belonging to the T-complex protein-1 (TCP-1) family, assist in the correct folding of nascent and misfolded proteins. It is well-known that in mammals, the zeta subunit of the TCP-1 complex (TCP-1ζ) plays a vital role in the folding and assembly of cytoskeleta proteins. This study reported for the first time the cloning, characterization and expression pattern analysis of the TCP-1ζ from Musca domestica, which was named as MdTCP-1ζ. The MdTCP-1ζ cDNA is 1,803 bp long with a 1,596 bp open reading frame that encodes a protein with 531 bp amino acids...
July 1, 2017: Journal of Insect Science
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