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Chatake T, Yanagisawa Y, Inoue R, Sugiyama M, Matsuo T, Fujiwara S, Ohsugi T, Sumi H. Purification and structural characterization of water‐soluble menaquinone‐7 produced by
Bacillus subtilis natto. J Food Biochem 2018. [DOI: 10.1111/jfbc.12630] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Kawahara T, Hanzawa N, Sugiyama M. Effect of Lactobacillus strains on thymus and chemokine expression in keratinocytes and development of atopic dermatitis-like symptoms. Benef Microbes 2018; 9:643-652. [PMID: 29798706 DOI: 10.3920/bm2017.0162] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Lactobacillus strains, a major group of lactic acid bacteria, are representative food microorganisms that have many potential beneficial effects via their interactions with immune and intestinal epithelial cells. However, little is known about the effect of Lactobacillus strains on atopic dermatitis via keratinocytes, which comprise the physical barrier of the skin. In this study, we report that Lactobacillus strains have a significant suppressive effect on tumour necrosis factor (TNF)-α-induced expression and production of thymus and activation-regulated chemokine (TARC), a T helper 2 cell chemokine responsible for atopic dermatitis, in human keratinocytes. An RNA interference study showed that the effect of Lactobacillus reuteri strain Japan Collection of Microorganisms (JCM) 1112, the most suppressive strain, depended on the presence of Toll-like receptor 2 and the induction of A20 (also known as TNF-α-induced protein 3) and cylindromatosis in HaCaT cells. Topical application of a water-soluble extract of homogenised JCM 1112 cells significantly suppressed the development of house dust mite-induced atopic skin lesions and TARC expression at the lesion sites in NC/Nga mice. Our study provides new insights into the use of Lactobacillus strains as suppressive agents against keratinocyte-involved atopic inflammation of the skin.
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Saeki A, Sugiyama M, Hasebe A, Suzuki T, Shibata K. Activation of NLRP3 inflammasome in macrophages by mycoplasmal lipoproteins and lipopeptides. Mol Oral Microbiol 2018; 33:300-311. [PMID: 29682880 DOI: 10.1111/omi.12225] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/17/2018] [Indexed: 12/29/2022]
Abstract
The NLRP3 inflammasome, an intracellular sensor consisting of the nucleotide-binding oligomerization domain-like receptor family, pyrin domain containing 3 (NLRP3), the adaptor protein apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC), and procaspase-1, plays critical roles in host defense against microbial pathogens by inducing production of interleukin-1β (IL-1β) and IL-18. Mycoplasma salivarium and Mycoplasma pneumoniae cells activated murine bone marrow-derived macrophages (BMMs) to induce production of IL-1α, IL-1β, and IL-18. The IL-1β production-inducing activities of these mycoplasmas toward BMMs from Toll-like receptor 2 (TLR2)-deficient mice were significantly attenuated compared with those from C57BL/6 mice (B6BMMs). This result suggests the possibility that their lipoproteins as TLR2 agonists are involved in the activity. Lipoproteins of M. salivarium and M. pneumoniae (MsLP and MpLP), and the M. salivarium-derived lipopeptide FSL-1 induced IL-1β production by B6BMMs, but not by BMMs from caspase-1-, NLRP3- or ASC-deficient mice. The activities of MsLP and MpLP were not downregulated by the proteinase K treatment, suggesting that the active sites are their N-terminal lipopeptide moieties. B6BMMs internalized the mycoplasmal N-terminal lipopeptide FSL-1 at least 30 min after incubation, FSL-1-containing endosomes started to fuse with the lysosomes around 2 hours, and then FSL-1 translocated into the cytosol from LAMP-1+ endosomes. The artificial delivery of FSL-1 into the cytosol of B6BMMs drastically enhanced the IL-1β production-inducing activity. FSL-1 as well as the representative NLRP3 inflammasome activator nigericin induced the NLRP3/ASC speck, but FSL-1 located in a compartment different from the NLRP3/ASC speck.
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Tamori A, Abiru S, Enomoto H, Kioka K, Korenaga M, Tani J, Enomoto M, Sugiyama M, Masaki T, Kawada N, Yatsuhashi H, Nishiguchi S, Mizokami M. Low incidence of hepatitis B virus reactivation and subsequent hepatitis in patients with chronic hepatitis C receiving direct-acting antiviral therapy. J Viral Hepat 2018; 25:608-611. [PMID: 29194858 DOI: 10.1111/jvh.12840] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 10/30/2017] [Indexed: 12/26/2022]
Abstract
To determine the clinical characteristics of hepatitis B virus (HBV) reactivation in patients undergoing interferon-free antihepatitis C virus (HCV) therapy, we examined HBV DNA in 25 HBV co-infected patients and 765 patients with resolved HBV infection during and after treatment with direct-acting antiviral agents (DAAs). Among those with HCV genotype 1, asunaprevir plus daclatasvir was administered to 160 patients, sofosbuvir (SOF) plus ledipasvir to 438 patients and paritaprevir plus ombitasvir and ritonavir to 25 patients. In total, 167 patients with genotype 2 were treated with SOF plus ribavirin. Three patients with an HBV DNA level ≥2000 IU/mL were treated with entecavir before anti-HCV therapy, without reactivation of HBV. In 3 of 22 (12%) HBV surface antigen (HBsAg)-positive patients with an HBV DNA level <2000 IU/mL, the viral load increased during treatment. However, hepatitis flare did not occur in these patients. There was no significant difference in clinical history between patients with and without HBV reactivation. Among 765 patients with resolved HBV infection, HBV reactivation occurred in 1 (0.1%) patient after initial resolution, whose HBV DNA level spontaneously decreased after DAA therapy. We compared anti-HBs titres at baseline with those at post-DAA therapy in 123 patients without HBsAg. There was no significant difference in anti-HBs levels between the two points (P = .79). In conclusion, HBV reactivation was rare in HBsAg-negative patients treated with DAA therapy. Additionally, hepatitis did not occur in HBV-reactivated patients with a baseline HBV DNA level <2000 IU/mL before DAA therapy.
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Takata T, Nakamura-Hirota T, Inoue R, Morishima K, Sato N, Sugiyama M, Fujii N. Asp 58 modulates lens αA-crystallin oligomer formation and chaperone function. FEBS J 2018; 285:2263-2277. [PMID: 29676852 DOI: 10.1111/febs.14475] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 04/02/2018] [Accepted: 04/13/2018] [Indexed: 11/28/2022]
Abstract
Senile cataract onset is caused by insolubilization of lens proteins. The lens crystallin protein family correctly orders the formation of homo- or hetero-oligomers in lens fiber cells. Because lens fiber cells do not divide, covalent post-translational modifications, such as isomerization of aspartate residues, accumulate with aging. Although many isomerization sites of αA-crystallin have been reported, their structural and functional contributions have never been identified. In this study, αA-crystallin was extracted from aged human lens and separated into each oligomeric state by size exclusion chromatography and electrophoresis. The novel combination methodology of in-solution/gel tryptic digestion with liquid chromatography equipped with mass spectrometry (LC-MS/MS) was used to evaluate the isomerization of Asp 58. The contributions of isomerization to assembly, solubility, and chaperone functions of αA-crystallin were estimated using a series of mutations of Asp 58 in αA-crystallin. The results indicated that the isomerization of Asp 58 depended on the oligomer size and age of the lens. The substitution of Asp 58 for hydrophobic residues increased αA-crystallin oligomer size and decreased solubility. All substitutions decreased the chaperone function of αA-crystallin for aggregates of bovine βL-crystallin and alcohol dehydrogenase. The data indicated that Asp 58 in αA-crystallin was critical for intermolecular interactions in the lens. Our results also suggested that LC-MS/MS-based isomerization analyses of in-gel-digested products could be useful for investigating the isomerization of Asp residues in oligomeric states. This method could also be used to analyze d/l ratios of amino acid residues in soluble protein aggregates.
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Kawanishi H, Tsuchiya T, Nishiki M, Sugiyama M, Ezaki H. Removal of Protein-Bound Substance in Hepatic Failure: Polyetherurethane Sheet Embedded with Powdered Charcoal (UPC). Int J Artif Organs 2018. [DOI: 10.1177/039139888400700611] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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57
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Nagata Y, Nishikawa T, Suginome M, Sato S, Sugiyama M, Porcar L, Martel A, Inoue R, Sato N. Elucidating the Solvent Effect on the Switch of the Helicity of Poly(quinoxaline-2,3-diyl)s: A Conformational Analysis by Small-Angle Neutron Scattering. J Am Chem Soc 2018; 140:2722-2726. [PMID: 29444565 DOI: 10.1021/jacs.7b11626] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Small-angle neutron scattering (SANS) was used to examine dilute solutions of a poly(quinoxaline-2,3-diyl) (PQX) with (R)-2-octyloxymethyl side chains in deuterated THF or a mixture of deuterated 1,1,2-TCE and THF (8/2, v/v), in which the PQX adopts pure P- and M-helical structures. The structures of the PQX that were obtained based on the SANS experiments in combination with theoretical calculations suggest that in THF, the chiral side chains of the P-helical PQX are extended, whereas in the 1,1,2-TCE/THF mixture, the side chains of the M-helical PQX are folded. Consequently, P-helical structures should be preferred in good solvents such as THF, which solvate the extended side chains, whereas M-helical structures should be preferred in poor solvents such as 1,1,2-TCE, wherein the side chains adopt shrunken conformations with maximized van der Waals interactions between the side chains. This study thus reveals the first example for fully determined nuanced conformations of the side chains of synthetic polymers in solution based on SANS experiments and theoretical calculations.
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Yagi-Utsumi M, Sikdar A, Kozai T, Inoue R, Sugiyama M, Uchihashi T, Yagi H, Satoh T, Kato K. Conversion of functionally undefined homopentameric protein PbaA into a proteasome activator by mutational modification of its C-terminal segment conformation. Protein Eng Des Sel 2017; 31:29-36. [DOI: 10.1093/protein/gzx066] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 12/06/2017] [Indexed: 01/10/2023] Open
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Kato D, Osakabe A, Arimura Y, Mizukami Y, Horikoshi N, Saikusa K, Akashi S, Nishimura Y, Park SY, Nogami J, Maehara K, Ohkawa Y, Matsumoto A, Kono H, Inoue R, Sugiyama M, Kurumizaka H. Crystal structure of the overlapping dinucleosome composed of hexasome and octasome. Science 2017; 356:205-208. [PMID: 28408607 DOI: 10.1126/science.aak9867] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Accepted: 03/17/2017] [Indexed: 12/19/2022]
Abstract
Nucleosomes are dynamic entities that are repositioned along DNA by chromatin remodeling processes. A nucleosome repositioned by the switch-sucrose nonfermentable (SWI/SNF) remodeler collides with a neighbor and forms the intermediate "overlapping dinucleosome." Here, we report the crystal structure of the overlapping dinucleosome, in which two nucleosomes are associated, at 3.14-angstrom resolution. In the overlapping dinucleosome structure, the unusual "hexasome" nucleosome, composed of the histone hexamer lacking one H2A-H2B dimer from the conventional histone octamer, contacts the canonical "octasome" nucleosome, and they intimately associate. Consequently, about 250 base pairs of DNA are left-handedly wrapped in three turns, without a linker DNA segment between the hexasome and octasome moieties. The overlapping dinucleosome structure may provide important information to understand how nucleosome repositioning occurs during the chromatin remodeling process.
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Hibino E, Inoue R, Sugiyama M, Kuwahara J, Matsuzaki K, Hoshino M. Identification of heteromolecular binding sites in transcription factors Sp1 and TAF4 using high-resolution nuclear magnetic resonance spectroscopy. Protein Sci 2017; 26:2280-2290. [PMID: 28857320 PMCID: PMC5654864 DOI: 10.1002/pro.3287] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 08/26/2017] [Accepted: 08/28/2017] [Indexed: 01/17/2023]
Abstract
The expression of eukaryotic genes is precisely controlled by interactions between general transcriptional factors and promoter-specific transcriptional activators. The fourth element of TATA-box binding protein-associated factor (TAF4), an essential subunit of the general transcription factor TFIID, serves as a coactivator for various promoter-specific transcriptional regulators. Interactions between TAF4 and site-specific transcriptional activators, such as Sp1, are important for regulating the expression levels of genes of interest. However, only limited information is available on the molecular mechanisms underlying the interactions between these transcriptional regulatory proteins. We herein analyzed the interaction between the transcriptional factors Sp1 and TAF4 using high-resolution solution nuclear magnetic resonance spectroscopy. We found that four glutamine-rich (Q-rich) regions in TAF4 were largely disordered under nearly physiological conditions. Among them, the first Q-rich region in TAF4 was essential for the interaction with another Q-rich region in the Sp1 molecule, most of which was largely disordered. The residues responsible for this interaction were specific and highly localized in a defined region within a range of 20-30 residues. Nevertheless, a detailed analysis of 13 C-chemical shift values suggested that no significant conformational change occurred upon binding. These results indicate a prominent and exceptional binding mode for intrinsically disordered proteins other than the well-accepted concept of "coupled folding and binding."
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Bernadó P, Shimizu N, Zaccai G, Kamikubo H, Sugiyama M. Solution scattering approaches to dynamical ordering in biomolecular systems. Biochim Biophys Acta Gen Subj 2017; 1862:253-274. [PMID: 29107147 DOI: 10.1016/j.bbagen.2017.10.015] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 10/23/2017] [Accepted: 10/24/2017] [Indexed: 01/09/2023]
Abstract
Clarification of solution structure and its modulation in proteins and protein complexes is crucially important to understand dynamical ordering in macromolecular systems. Small-angle x-ray scattering (SAXS) and small-angle neutron scattering (SANS) are among the most powerful techniques to derive structural information. Recent progress in sample preparation, instruments and software analysis is opening up a new era for small-angle scattering. In this review, recent progress and trends of SAXS and SANS are introduced from the point of view of instrumentation and analysis, touching on general features and standard methods of small-angle scattering. This article is part of a Special Issue entitled "Biophysical Exploration of Dynamical Ordering of Biomolecular Systems" edited by Dr. Koichi Kato.
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Sugiyama M, Seki J. In vivo application of lipoproteins as drug carriers: pharmacological evaluation of sterylglucoside-lipoprotein complexes. TARGETED DIAGNOSIS AND THERAPY 2017; 5:315-50. [PMID: 1797170 DOI: 10.1201/9780203748831-10] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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63
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Trewhella J, Duff AP, Durand D, Gabel F, Guss JM, Hendrickson WA, Hura GL, Jacques DA, Kirby NM, Kwan AH, Pérez J, Pollack L, Ryan TM, Sali A, Schneidman-Duhovny D, Schwede T, Svergun DI, Sugiyama M, Tainer JA, Vachette P, Westbrook J, Whitten AE. 2017 publication guidelines for structural modelling of small-angle scattering data from biomolecules in solution: an update. Acta Crystallogr D Struct Biol 2017; 73:710-728. [PMID: 28876235 PMCID: PMC5586245 DOI: 10.1107/s2059798317011597] [Citation(s) in RCA: 181] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 08/07/2017] [Indexed: 12/02/2022] Open
Abstract
In 2012, preliminary guidelines were published addressing sample quality, data acquisition and reduction, presentation of scattering data and validation, and modelling for biomolecular small-angle scattering (SAS) experiments. Biomolecular SAS has since continued to grow and authors have increasingly adopted the preliminary guidelines. In parallel, integrative/hybrid determination of biomolecular structures is a rapidly growing field that is expanding the scope of structural biology. For SAS to contribute maximally to this field, it is essential to ensure open access to the information required for evaluation of the quality of SAS samples and data, as well as the validity of SAS-based structural models. To this end, the preliminary guidelines for data presentation in a publication are reviewed and updated, and the deposition of data and associated models in a public archive is recommended. These guidelines and recommendations have been prepared in consultation with the members of the International Union of Crystallography (IUCr) Small-Angle Scattering and Journals Commissions, the Worldwide Protein Data Bank (wwPDB) Small-Angle Scattering Validation Task Force and additional experts in the field.
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Oki E, Shimokawa M, Murata A, Takahashi T, Maeda K, Kusumoto T, Munemoto Y, Ando K, Nakanishi R, Sugiyama M, Nakashima Y, Saeki H, Saji S, Maehara Y. Effect of lateral lymph node dissection for lower rectal cancer: An ad hoc analysis of the ACTS-RC randomized clinical trial. Ann Oncol 2017. [DOI: 10.1093/annonc/mdx393.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Sugiyama M, Murayama H, Inagaki H, Ura C, Miyamae F, Edahiro A, Okamura T, Awata S. THE ASSOCIATION OF CHILDHOOD SOCIOECONOMIC DISADVANTAGE WITH COGNITIVE IMPAIRMENT IN OLDER JAPANESE. Innov Aging 2017. [DOI: 10.1093/geroni/igx004.931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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66
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Inagaki H, Sugiyama M, Ura C, Miyamae F, Edahiro A, Motokawa K, Murayama H, Awata S. ASSOCIATION BETWEEN MENTAL HEALTH AND PHYSICAL, COGNITIVE, SOCIAL FACTORS IN ELDERLY. Innov Aging 2017. [DOI: 10.1093/geroni/igx004.3101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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67
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Murayama H, Sugiyama M, Inagaki H, Ura C, Miyamae F, Edahiro A, Okamura T, Awata S. ARE NEIGHBORHOODS ASSOCIATED WITH THE LIKELIHOOD OF DEMENTIA? A STUDY IN THE TOKYO METROPOLITAN AREA. Innov Aging 2017. [DOI: 10.1093/geroni/igx004.640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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68
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Oba Y, Morooka S, Ohishi K, Suzuki JI, Takata SI, Sato N, Inoue R, Tsuchiyama T, Gilbert EP, Sugiyama M. Energy-resolved small-angle neutron scattering from steel. J Appl Crystallogr 2017. [DOI: 10.1107/s1600576717000279] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Recent progress of pulsed neutron sources has enabled energy-resolved analysis of neutron attenuation spectra, which include information on neutron scattering. In this study, a new analysis technique for small-angle neutron scattering (SANS) is demonstrated. A clear difference is observed in the neutron attenuation spectra between steels with different nanostructures; this difference can be understood as arising from attenuation due to SANS. The neutron attenuation spectra calculated from the corresponding SANS profiles agree well with the experimentally observed attenuation spectra. This result indicates that measurement of neutron attenuation spectra may enable the development of a novel experimental technique,i.e.energy-resolved SANS.
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Hibino E, Inoue R, Sugiyama M, Kuwahara J, Matsuzaki K, Hoshino M. Interaction between intrinsically disordered regions in transcription factors Sp1 and TAF4. Protein Sci 2016; 25:2006-2017. [PMID: 27515574 PMCID: PMC5079245 DOI: 10.1002/pro.3013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Accepted: 08/08/2016] [Indexed: 11/09/2022]
Abstract
The expression of eukaryotic genes is precisely controlled by specific interactions between general transcription initiation factors and gene-specific transcriptional activators. The general transcription factor TFIID, which plays an essential role in mediating transcriptional activation, is a multisubunit complex comprising the TATA box-binding protein (TBP) and multiple TBP-associated factors (TAFs). On the other hand, biochemical and genetic approaches have shown that the promoter-specific transcriptional activator Sp1 has the ability to interact with one of the components of TFIID, the TBP-associated factor TAF4. We herein report the structural details of the glutamine-rich domains (Q-domains) of Sp1 and TAF4 using circular dichroism (CD) and heteronuclear magnetic resonance (NMR) spectroscopy. We found that the two Q-domains of Sp1 and four Q-domains of TAF4 were disordered under physiological conditions. We also quantitatively analyzed the interaction between the Q-domains of Sp1 and TAF4 by NMR and surface plasmon resonance, and detected a weak but specific association between them. Nevertheless, a detailed analysis of CD spectra suggested that any significant conformational change did not occur concomitantly with this association, at least at the level of the overall secondary structure. These results may represent a prominent and exceptional binding mode for the IDPs, which are not categorized in a well-accepted concept of "coupled folding and binding."
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Sugiyama M, Yagi H, Ishii K, Porcar L, Martel A, Oyama K, Noda M, Yunoki Y, Murakami R, Inoue R, Sato N, Oba Y, Terauchi K, Uchiyama S, Kato K. Structural characterization of the circadian clock protein complex composed of KaiB and KaiC by inverse contrast-matching small-angle neutron scattering. Sci Rep 2016; 6:35567. [PMID: 27752127 PMCID: PMC5067715 DOI: 10.1038/srep35567] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 09/30/2016] [Indexed: 11/26/2022] Open
Abstract
The molecular machinery of the cyanobacterial circadian clock consists of three proteins: KaiA, KaiB, and KaiC. Through interactions among the three Kai proteins, the phosphorylation states of KaiC generate circadian oscillations in vitro in the presence of ATP. Here, we characterized the complex formation between KaiB and KaiC using a phospho-mimicking mutant of KaiC, which had an aspartate substitution at the Ser431 phosphorylation site and exhibited optimal binding to KaiB. Mass-spectrometric titration data showed that the proteins formed a complex exclusively in a 6:6 stoichiometry, indicating that KaiB bound to the KaiC hexamer with strong positive cooperativity. The inverse contrast-matching technique of small-angle neutron scattering enabled selective observation of KaiB in complex with the KaiC mutant with partial deuteration. It revealed a disk-shaped arrangement of the KaiB subunits on the outer surface of the KaiC C1 ring, which also serves as the interaction site for SasA, a histidine kinase that operates as a clock-output protein in the regulation of circadian transcription. These data suggest that cooperatively binding KaiB competes with SasA with respect to interaction with KaiC, thereby promoting the synergistic release of this clock-output protein from the circadian oscillator complex.
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Oba Y, Morooka S, Ohishi K, Sato N, Inoue R, Adachi N, Suzuki JI, Tsuchiyama T, Gilbert EP, Sugiyama M. Magnetic scattering in the simultaneous measurement of small-angle neutron scattering and Bragg edge transmission from steel. J Appl Crystallogr 2016; 49:1659-1664. [PMID: 27738416 PMCID: PMC5045730 DOI: 10.1107/s1600576716013133] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 08/15/2016] [Indexed: 11/10/2022] Open
Abstract
A technique for the analysis of magnetic scattering has been developed, where small-angle neutron scattering and Bragg edge transmission measurements are performed simultaneously. This technique is shown to provide crystallographic information for ferrite crystallites and nanostructural information for precipitates in steel. Pulsed neutron sources enable the simultaneous measurement of small-angle neutron scattering (SANS) and Bragg edge transmission. This simultaneous measurement is useful for microstructural characterization in steel. Since most steels are ferromagnetic, magnetic scattering contributions should be considered in both SANS and Bragg edge transmission analyses. An expression for the magnetic scattering contribution to Bragg edge transmission analysis has been derived. The analysis using this expression was applied to Cu steel. The ferrite crystallite size estimated from this Bragg edge transmission analysis with the magnetic scattering contribution was larger than that estimated using conventional expressions. This result indicates that magnetic scattering has to be taken into account for quantitative Bragg edge transmission analysis. In the SANS analysis, the ratio of magnetic to nuclear scattering contributions revealed that the precipitates consist of body-centered cubic Cu0.7Fe0.3 and pure Cu, which probably has 9R structure including elastic strain and vacancies. These results show that effective use of the magnetic scattering contribution allows detailed analyses of steel microstructure.
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Inoue R, Takata T, Fujii N, Ishii K, Uchiyama S, Sato N, Oba Y, Wood K, Kato K, Fujii N, Sugiyama M. New insight into the dynamical system of αB-crystallin oligomers. Sci Rep 2016; 6:29208. [PMID: 27381175 PMCID: PMC4933968 DOI: 10.1038/srep29208] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 06/14/2016] [Indexed: 01/21/2023] Open
Abstract
α-Crystallin possesses a dynamic quaternary structure mediated by its subunit dynamics. Elucidation of a mechanism of subunit dynamics in homo-oligomers of αB-crystallin was tackled through deuteration-assisted small-angle neutron scattering (DA-SANS) and electrospray ionization (ESI) native mass spectrometry (nMS). The existence of subunit exchange was confirmed with DA-SANS, and monomers liberated from the oligomers were observed with nMS. With increasing temperature, an increase in both the exchange rate and monomer population was observed despite the absence of oligomer collapse. It is proposed that transiently liberated subunits, namely, "traveling subunits," play a role in subunit exchange. Moreover, we propose that protein function is regulated by these traveling subunits.
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Nishida N, Ohashi J, Sugiyama M, Tsuchiura T, Yamamoto K, Hino K, Honda M, Kaneko S, Yatsuhashi H, Koike K, Yokosuka O, Tanaka E, Taketomi A, Kurosaki M, Izumi N, Sakamoto N, Eguchi Y, Sasazuki T, Tokunaga K, Mizokami M. Effects of HLA-DPB1 genotypes on chronic hepatitis B infection in Japanese individuals. ACTA ACUST UNITED AC 2015; 86:406-12. [PMID: 26449183 DOI: 10.1111/tan.12684] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 09/04/2015] [Accepted: 09/15/2015] [Indexed: 01/26/2023]
Abstract
Significant associations of HLA-DP alleles with chronic hepatitis B (CHB) infection are evident in Asian and Arabian populations, including Japanese, Han Chinese, Korean, and Saudi Arabian populations. Here, significant associations between CHB infection and five DPB1 alleles (two susceptibility alleles, DPB1(*) 05:01 and (*) 09:01, and three protective alleles, DPB1(*) 02:01, (*) 04:01, and (*) 04:02) were confirmed in a population comprising of 2582 Japanese individuals. Furthermore, odds ratios for CHB were higher for those with both DPB1 susceptibility alleles than for those with only one susceptibility allele; therefore, effects of susceptibility alleles were additive for risk of CHB infection. Similarly, protective alleles showed an additive effect on protection from CHB infection. Moreover, heterozygotes of any protective allele showed stronger association with CHB than did homozygotes, suggesting that heterozygotes may bind a greater variety of hepatitis B-derived peptides, and thus present these peptides more efficiently to T-cell receptors than homozygotes. Notably, compound heterozygote of the protective allele (any one of DPB1*02:01, *04:01, and *04:02) and the susceptible allele DPB1*05:01 was significantly associated with protection against CHB infection, which indicates that one protective HLA-DPB1 molecule can provide dominant protection. Identification of the HLA-DPB1 genotypes associated with susceptibility to and protection from CHB infection is essential for future analysis of the mechanisms responsible for immune recognition of hepatitis B virus antigens by HLA-DPB1 molecules.
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Sato N, Matsumiya A, Higashino Y, Funaki S, Kitao Y, Oba Y, Inoue R, Arisaka F, Sugiyama M, Urade R. Molecular Assembly of Wheat Gliadins into Nanostructures: A Small-Angle X-ray Scattering Study of Gliadins in Distilled Water over a Wide Concentration Range. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:8715-8721. [PMID: 26365302 DOI: 10.1021/acs.jafc.5b02902] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Gliadin, one of the major proteins together with glutenin composing gluten, affects the physical properties of wheat flour dough. In this study, nanoscale structures of hydrated gliadins extracted into distilled water were investigated primarily by small-angle X-ray scattering (SAXS) over a wide range of concentrations. Gliadins are soluble in distilled water below 10 wt %. Guinier analyses of SAXS profiles indicate that gliadins are present as monomers together with small amounts of dimers and oligomers in a very dilute solution. The SAXS profiles also indicate that interparticle interference appears above 0.5 wt % because of electrostatic repulsion among gliadin assemblies. Above 15 wt %, gliadins form gel-like hydrated solids. At greater concentrations, a steep upturn appears in the low-q region owing to the formation of large aggregates, and a broad shoulder appears in the middle-q region showing density fluctuation inside. This study demonstrates that SAXS can effectively disclose the nanostructure of hydrated gliadin assemblies.
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Fujimoto T, Nishino S, Shinmura C, Koma Y, Sugiyama M, Uejima S. Clinical study of the modified Caldwell-Luc operation by using 3-D image analysis. Int J Oral Maxillofac Surg 2015. [DOI: 10.1016/j.ijom.2015.08.087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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