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Jay M Bhatt, Adrian S Enriquez, Jinliang Wang, Humberto M Rojo, Sudheer K Molugu, Zacariah L Hildenbrand, Ricardo A Bernal
Chaperonins are macromolecular complexes found throughout all kingdoms of life that assist unfolded proteins reach a biologically active state. Historically, chaperonins have been classified into two groups based on sequence, subunit structure, and the requirement for a co-chaperonin. Here, we present a brief review of chaperonins that can form double- and single-ring conformational intermediates in their protein-folding catalytic pathway. To date, the bacteriophage encoded chaperonins ϕ-EL and OBP, human mitochondrial chaperonin and most recently, the bacterial groEL/ES systems, have been reported to form single-ring intermediates as part of their normal protein-folding activity...
2018: Frontiers in Molecular Biosciences
Andrey Dyachenko, Sem Tamara, Albert J R Heck
The GroES heptamer is the molecular co-chaperonin that partners with the tetradecamer chaperonin GroEL, which assists in the folding of various nonnative polypeptide chains in Escherichia coli. Gp31 is a structural and functional analogue of GroES encoded by the bacteriophage T4, becoming highly expressed in T4-infected E. coli, taking over the role of GroES, favoring the folding of bacteriophage proteins. Despite being slightly larger, gp31 is quite homologous to GroES in terms of its tertiary and quaternary structure, as well as in its function and mode of interaction with the chaperonin GroEL...
May 7, 2018: Journal of the American Society for Mass Spectrometry
Keith R Willison
The cytosolic chaperonin CCT (chaperonin containing TCP-1) is an ATP-dependent double-ring protein machine mediating the folding of members of the eukaryotic cytoskeletal protein families. The actins and tubulins are obligate substrates of CCT because they are completely dependent on CCT activity to reach their native states. Genetic and proteomic analysis of the CCT interactome in the yeast Saccharomyces cerevisiae revealed a CCT network of approximately 300 genes and proteins involved in many fundamental biological processes...
June 19, 2018: Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences
D Thirumalai, Changbong Hyeon
Signal transmission at the molecular level in many biological complexes occurs through allosteric transitions. Allostery describes the responses of a complex to binding of ligands at sites that are spatially well separated from the binding region. We describe the structural perturbation method, based on phonon propagation in solids, which can be used to determine the signal-transmitting allostery wiring diagram (AWD) in large but finite-sized biological complexes. Application to the bacterial chaperonin GroEL-GroES complex shows that the AWD determined from structures also drives the allosteric transitions dynamically...
June 19, 2018: Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences
Daisuke Noshiro, Toshio Ando
A double-ring-shaped tetradecameric GroEL complex assists proper protein folding in cooperation with the cochaperonin GroES. The dynamic GroEL-GroES interaction reflects the allosteric intra- and inter-ring communications and the chaperonin reaction. Therefore, revealing this dynamic interaction is essential to understanding the allosteric communications and the operation mechanism of GroEL. Nevertheless, how this interaction proceeds in the chaperonin cycle has long been controversial. Here, we directly image the dynamic GroEL-GroES interaction under conditions with and without foldable substrate protein using high-speed atomic force microscopy...
June 19, 2018: Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences
George H Lorimer, Xue Fei, Xiang Ye
In response to the binding of ATP, the two heptameric rings of the GroEL chaperonin protein interact with one another in a negatively cooperative manner. Owing to the helix dipole, the positively charged nitrogen of glycine 88 at the N-terminus of helix D binds to oxygen atoms on the β and γ phosphorus atoms of ATP. In apo-GroEL, the nucleotide-binding sites of different rings are connected to one another by the interaction of the ɛ-amino group of lysine 105 of one helix D across the twofold axis with the negatively charged carbonyl oxygen atom of alanine 109 at the C-terminus of the other helix D...
June 19, 2018: Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences
Qianli Meng, Bingbing X Li, Xiangshu Xiao
The 60 kDa heat shock protein (Hsp60) is classically known as a mitochondrial chaperonin protein working together with co-chaperonin 10 kDa heat shock protein (Hsp10). This chaperonin complex is essential for folding proteins newly imported into mitochondria. However, Hsp60, and/or Hsp10 have also been shown to reside in other subcellular compartments including extracellular space, cytosol, and nucleus. The proteins in these extra-mitochondrial compartments may possess a wide range of functions dependent or independent of its chaperoning activity...
2018: Frontiers in Molecular Biosciences
Xu Dong-Po, Fang Di-An, Zhao Chang-Sheng, Jiang Shu-Lun, Hu Hao-Yuan
HSP90β1 (known as glyco-protein 96, GP96) is a vital endoplasmic reticulum (ER) depended chaperonin among the HSPs (heat shock proteins) family. Furthermore, it always processes and presents antigen of the tumor and keeps balance for the intracellular environment. In the present study, we explored the effect of tributyltin chloride (TBT-Cl) exposure on HSP90β1 expression in river pufferfish, Takifugu obscurus. The full length of To-HSP90β1 was gained with 2775 bp in length, with an ORF (open reading frame) encoding an 803 aa polypeptide...
April 30, 2018: Gene
Mohammed Y Ansari, Shekhar C Mande
Chaperonins are a subclass of molecular chaperones that assist cellular proteins to fold and assemble into their native shape. Much work has been done on Type I chaperonins, which has elucidated their elegant mechanism. Some debate remains about the details in these mechanisms, but nonetheless the roles of these in helping protein folding have been understood in great depth. In this review we discuss the known functions of atypical Type I chaperonins, highlighting evolutionary aspects that might lead chaperonins to perform alternate functions...
2018: Frontiers in Molecular Biosciences
Xiong Deng, Yue Liu, Xuexin Xu, Dongmiao Liu, Genrui Zhu, Xing Yan, Zhimin Wang, Yueming Yan
In this study, we performed the first comparative proteomic analysis of wheat flag leaves and developing grains in response to drought stress. Drought stress caused a significant decrease in several important physiological and biochemical parameters and grain yield traits, particularly those related to photosynthesis and starch biosynthesis. In contrast, some key indicators related to drought stress were significantly increased, including malondialdehyde, soluble sugar, proline, glycine betaine, abscisic acid content, and peroxidase activity...
2018: Frontiers in Plant Science
Peng Zeng, Tao Shen
Bardet-Biedl syndrome (BBS) is a rare genetic disease caused by ciliary structure abnormality or dysfunction. To date, more than 21 BBS genes (BBS1 - 21) have been reported to independently cause the disorder. Although the cellular functions of BBS proteins are not yet fully understood, model organisms have revealed that such proteins are involved in ciliary functions and intracellular transport. Among the 21 BBS genes, BBS7 is unique in that its product is a subunit of the BBSome and can directly interact with the BBS chaperonin complex...
April 10, 2018: Zhonghua Yi Xue Yi Chuan Xue za Zhi, Zhonghua Yixue Yichuanxue Zazhi, Chinese Journal of Medical Genetics
Amie Maher, Kara Staunton, Kevin Kavanagh
A potential role for bacteria in the induction of rosacea has been suggested. The aim of this work was to characterize the effect of temperature on the production of immunostimulatory proteins by Bacillus oleronius-a bacterium to which rosacea patients show sera reactivity and which was originally isolated from a Demodex mite from a rosacea patient. The affected skin of rosacea patients is at a higher temperature than unaffected skin and it was postulated that this might alter the protein expression pattern of B...
April 10, 2018: Pathogens and Disease
Haixia Chi, Baomei Xu, Zhenzhen Liu, Junting Wei, Shixin Li, Hao Ren, Yan Xu, Xinwei Lu, Xiaojuan Wang, Xiaoqiang Wang, Fang Huang
GroEL along with ATP and its co-chaperonin GroES has been demonstrated to significantly enhance the folding of newly translated G-protein-coupled receptors (GPCRs). This work extends the previous studies to explore the guest capture and release processes in GroEL-assisted folding of GPCRs, by the reduced approach of employing CXCR4 transmembrane peptides as model substrates. Each of the CXCR4-derived peptides exhibited high affinity for GroEL with a binding stoichiometry near seven. It is found that the peptides interact with the paired α helices in the apical domain of the chaperonin which are similar with the binding sites of SBP (strongly binding peptide: SWMTTPWGFLHP)...
April 5, 2018: Biochimica et Biophysica Acta
Huping Wang, Wenyu Han, Junichi Takagi, Yao Cong
Cryo-electron microscopy (cryo-EM) has been established as one of the central tools in the structural study of macromolecular complexes. Although intermediate- or low-resolution structural information through negative staining (NS) or cryo-EM analysis remains highly valuable, we lack general and efficient ways to achieve unambiguous subunit identification in these applications. Here, we took advantage of the extremely high affinity between a dodecapeptide "PA" tag and the NZ-1 antibody Fab fragment to develop an efficient "yeast inner-subunit PA-NZ-1 labeling" (YISPANL) strategy that when combined with cryo-EM could precisely identify subunits in macromolecular complexes...
April 3, 2018: Journal of Molecular Biology
Xiaojing Yang, Hanru Ren, Yuhui Shao, Yi Sun, Lihua Zhang, Hongling Li, Xiulong Zhang, Xinmiao Yang, Weiwei Yu, Jie Fu
The chaperonin-containing T‑complex protein 1 (CCT) has eight subunits, CCT 1-8, which are dysregulated in several types of cancer. To determine how subunit 8 (CCT8) influences the development of esophageal squamous cell carcinoma (ESCC), immunohistochemistry and western blot analysis were performed on 128 ESCC samples in the present study to measure the expression of CCT8. The prognostic value of CCT8 was analyzed using univariate and multivariate survival analyses. CCT8 knockdown in ESCC cells was performed and subsequently, the migration and invasion of ESCC cells was assessed...
March 27, 2018: International Journal of Oncology
Anna Vitlin Gruber, Leila Feiz
Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) catalyzes the rate-limiting step in the Calvin-Benson cycle, which transforms atmospheric carbon into a biologically useful carbon source. The slow catalytic rate of Rubisco and low substrate specificity necessitate the production of high levels of this enzyme. In order to engineer a more efficient plant Rubisco, we need to better understand its folding and assembly process. Form I Rubisco, found in green algae and vascular plants, is a hexadecamer composed of 8 large subunits (RbcL), encoded by the chloroplast genome and 8 small, nuclear-encoded subunits (RbcS)...
2018: Frontiers in Molecular Biosciences
Robert H Wilson, Manajit Hayer-Hartl
Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), a ~550 kDa complex of eight large (RbcL) and eight small subunits (RbcS), mediates the fixation of atmospheric CO2 into usable sugars during photosynthesis. Despite its fundamental role, Rubisco is a remarkably inefficient enzyme and thus is produced by plants in huge amounts. It has long been a key target for bioengineering with the goal to increase crop yields. However, such efforts have been hampered by the complex requirement of Rubisco biogenesis for molecular chaperones...
March 28, 2018: Biochemistry
Naoki Ogawa, Yohei Y Yamamoto, Keisuke Abe, Hiroshi Sekiguchi, Yuji C Sasaki, Akira Ishikawa, Judith Frydman, Masafumi Yohda
Previously, we demonstrated the ATP-dependent dynamics of a group II chaperonin at the single-molecule level by diffracted X-ray tracking (DXT). The disadvantage of DXT is that it requires a strong X-ray source and also perfect gold nano-crystals. To resolve this problem, we developed diffracted electron tracking (DET). Electron beams have scattering cross-sections that are approximately 1000 times larger than those of X-rays. Thus, DET enables us to perform super-accurate measurements of the time-resolved 3D motion of proteins labeled with commercially available gold nanorods using a scanning electron microscope...
March 22, 2018: International Journal of Molecular Sciences
Dario Spigolon, D Travis Gallagher, Adrian Velazquez-Campoy, Donatella Bulone, Jatin Narang, Pier Luigi San Biagio, Francesco Cappello, Alberto J L Macario, Everly Conway de Macario, Frank T Robb
The human chaperonin complex is a ~ 1 MDa nanomachine composed of two octameric rings formed from eight similar but non-identical subunits called CCT. Here, we are elucidating the mechanism of a heritable CCT5 subunit mutation that causes profound neuropathy in humans. In previous work, we introduced an equivalent mutation in an archaeal chaperonin that assembles into two octameric rings like in humans but in which all subunits are identical. We reported that the hexadecamer formed by the mutant subunit is unstable with impaired chaperoning functions...
December 2017: Biochemistry and Biophysics Reports
Yani Zhao, Pawel Dabrowski-Tumanski, Szymon Niewieczerzal, Joanna I Sulkowska
The folding of proteins with a complex knot is still an unresolved question. Based on representative members of Ubiquitin C-terminal Hydrolases (UCHs) that contain the 52 knot in the native state, we explain how UCHs are able to unfold and refold in vitro reversibly within the structure-based model. In particular, we identify two, topologically different folding/unfolding pathways and corroborate our results with experiment, recreating the chevron plot. We show that confinement effect of chaperonin or weak crowding greatly facilitates folding, simultaneously slowing down the unfolding process of UCHs, compared with bulk conditions...
March 16, 2018: PLoS Computational Biology
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