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71.
Studies on DNA markers (D4S10 and D4S43/S127) genetically linked to Huntington's disease in Japanese families 总被引:1,自引:0,他引:1
Ichiro Kanazawa Ikuko Kondo Joh-E Ikeda Teruaki Ikeda Yuichior Shizu Mitsuo Yoshida Hirotaro Narabayashi Shigetoshi Kuroda Hisayuki Tsunoda Eiji Mizuta Yoko Okuno Kiyotaka Sugawara Miho Murata Mafuyu Takahashi James F. Gusella 《Human genetics》1990,85(3):257-260
Summary This is the first full report on the genetic linkage between Japanese Huntington's disease and the DNA markers D4S10 and D4S43/S127. With use of the HindIII, BglI, and EcoRI polymorphisms detected at D4S10, and the combination of all these polymorphisms to give composite haplotypes, nine Japanese Huntington's disease families were found to be informative. Three recombinants for D4S10 were detected in these families, giving a maximum lod score of 1.662 at a of 0.10. Similarly, when we used the MspI and PvuII polymorphisms detected by D4S43/S127, five families gave informative results. No recombinant was detected in these families, giving a maximum lod score of 3.348 at a of 0.00. These results clearly support the view that the Japanese Huntington's disease gene may be identical with the Western gene, in spite of the lower prevalence rate in Japan. 相似文献
72.
Nakao R Tashiro Y Nomura N Kosono S Ochiai K Yonezawa H Watanabe H Senpuku H 《Biochemical and biophysical research communications》2008,365(4):784-789
OMP85 is a highly conserved outer membrane protein in all Gram-negative bacteria. We studied an uncharacterized OMP85 homolog of Porphyromonas gingivalis, a primary periodontal pathogen forming subgingival plaque biofilms. Using an outer-loop peptide antibody specific for the OMP85 of P. gingivalis, loop-3 Ab, we found a difference in the mobility of OMP85 on SDS-PAGE gel between the P. gingivalis wild-type and the isogenic galE mutant, a deglycosylated strain, suggesting that OMP85 naturally exists in a glycosylated form. This was also supported by a shift in OMP85 PAGE mobility after chemical deglycosylation treatment. Further, loop-3 Ab cross-reacted with the galE mutant stronger than the wild-type strain; and could inhibit biofilm formation in the galE mutant more than in the wild-type strain. In conclusion, this is the first report providing the evidence of OMP85 glycosylation and the involvement of OMP85 in biofilm formation. 相似文献
73.
Toshihiko Sugiki Chie Yoshiura Yutaka Kofuku Takumi Ueda Ichio Shimada Hideo Takahashi 《Protein science : a publication of the Protein Society》2009,18(5):1115-1120
Protein aggregation is an essential molecular event in a wide variety of biological situations, and is a causal factor in several degenerative diseases. The aggregation of proteins also frequently hampers structural biological analyses, such as solution NMR studies. Therefore, precise detection and characterization of protein aggregation are of crucial importance for various research fields. In this study, we demonstrate that fluorescence correlation spectroscopy (FCS) using a single‐molecule fluorescence detection system enables the detection of otherwise invisible aggregation of proteins at higher protein concentrations, which are suitable for structural biological experiments, and consumes relatively small amounts of protein over a short measurement time. Furthermore, utilizing FCS, we established a method for high‐throughput screening of protein aggregation and optimal solution conditions for structural biological experiments. 相似文献
74.
Ni Hou Hideo Mogami Chisato Kubota-Murata Meng Sun Toshiyuki Takeuchi Seiji Torii 《PloS one》2012,7(10)
Newly synthesized hormones have been suggested to be preferentially secreted by various neuroendocrine cells. This observation indicates that there is a distinct population of secretory granules containing new and old hormones. Recent development of fluorescent timer proteins used in bovine adrenal chromaffin cells revealed that secretory vesicles segregate into distinct age-dependent populations. Here, we verify the preferential release of newly synthesized insulin in the pancreatic β-cell line, MIN6, using a combination of multi-labeling reporter systems with both fluorescent and biochemical procedures. This system allows hormones or granules of any age to be labeled, in contrast to the timer proteins, which require fluorescence shift time. Pulse-chase labeling with different color probes distinguishes insulin secretory granules by age, with younger granules having a predominantly intracellular localization rather than at the cell periphery. 相似文献
75.
76.
Dietary antioxidants fail in protection against oxidative genetic damage in in vitro evaluation 总被引:1,自引:0,他引:1
Sun M Sakakibara H Ashida H Danno G Kanazawa K 《Bioscience, biotechnology, and biochemistry》2000,64(11):2395-2401
Carcinogenesis is believed to be induced through the oxidative damage of DNA, and antioxidants are expected to suppress it. So, the polyphenolic antioxidants in daily foods were investigated to see whether they protect against genetic damage by active oxygen. In the evaluation, we used a bioassay and a chemical determination, a Salmonella mutagenicity test for mutation by a N-hydroxyl radical from one of the dietary carcinogens 3-amino-1-methyl-5H-pyrido[4,3-b]indole and the formation of 8-hydroxyl (8-OHdG) from 2'-deoxyguanosine (2'-dG) in a Fenton OH-radical generating system. Thirty-one antioxidants including flavonoids were compared in terms of radical-trapping activity with bacterial DNA and 2'-dG. Antioxidants inhibited the mutation but the IC50 values were in the mM order. Against 8-OHdG formation, only alpha-tocopherol had a suppressive effect with an IC50 of 1.5 microM. Thus, except alpha-tocopherol, the dietary antioxidants did not scavenge the biological radicals faster than bacterial DNA and intact 2'-dG, indicating that they failed to prevent oxidative gene damage and probably carcinogenesis. 相似文献
77.
Yoichiro Fujioka Shinya Nishide Toyoyuki Ose Tadaki Suzuki Izumi Kato Hideo Fukuhara Mari Fujioka Kosui Horiuchi Aya O. Satoh Prabha Nepal Sayaka Kashiwagi Jing Wang Mika Horiguchi Yuko Sato Sarad Paudel Asuka Nanbo Tadaaki Miyazaki Hideki Hasegawa Yusuke Ohba 《Cell host & microbe》2018,23(6):809-818.e5
78.
Functional assembly of the Helicobacter pylori Na+/H+ antiporter (HPNhaA) from partial fragments was studied. Expression plasmids encoding a series of complementary N- and C-terminal fragment pairs containing the transmembrane domains (TMs) were constructed by inserting a stop or a start codon into each of the loop regions of NhaA. HPNhaA fragments alone or complementary fragment pairs were expressed in DeltanhaA Escherichia coli, and fragment integration into the membrane and antiporter activity were measured. TM1-10, TM1-11, TM2-12, TM6-12, and TM10-12 were found in the membrane fraction, while the other fragments were not. While no single fragment displayed antiporter activity, simultaneous expression of fragments in certain pairs, such as TM1-2 + TM3-12, TM1-8 + TM9-12, or TM1-11 + TM12, reconstituted antiporter activity. With the exception of TM12, all of the fragments in the pairs were detected in the membrane. No single fragments expressed alone for these pairs were found in the membrane, except for TM1-11, suggesting that the interaction between the fragments in these pairs stabilized the fragments and enabled reconstitution of HPNhaA. We also found that the simultaneous expression of three complementary fragments (TM1-2 + TM3-8 + TM9-12) reconstituted HPNhaA activity. Other pairs that were found in the membrane (TM1-5 + TM6-12, TM1-10 + TM11-12, and TM1 + TM2-12) did not reconstitute antiporter activity, suggesting that they may not have the proper conformation. These results revealed that the ability to reconstitute antiporter activity depends on the split position in the loop regions and the interaction between complementary fragment pairs. We propose that formation of the active HPNhaA molecule is initiated by the interaction of short-lived intermediates and maintained by the increased stability of the intermediates within the resulting complex. 相似文献
79.
Small proline-rich protein 1A is a gp130 pathway- and stress-inducible cardioprotective protein 下载免费PDF全文
Pradervand S Yasukawa H Muller OG Kjekshus H Nakamura T St Amand TR Yajima T Matsumura K Duplain H Iwatate M Woodard S Pedrazzini T Ross J Firsov D Rossier BC Hoshijima M Chien KR 《The EMBO journal》2004,23(22):4517-4525
The interleukin-6 cytokines, acting via gp130 receptor pathways, play a pivotal role in the reduction of cardiac injury induced by mechanical stress or ischemia and in promoting subsequent adaptive remodeling of the heart. We have now identified the small proline-rich repeat proteins (SPRR) 1A and 2A as downstream targets of gp130 signaling that are strongly induced in cardiomyocytes responding to biomechanical/ischemic stress. Upregulation of SPRR1A and 2A was markedly reduced in the gp130 cardiomyocyte-restricted knockout mice. In cardiomyocytes, MEK1/2 inhibitors prevented SPRR1A upregulation by gp130 cytokines. Furthermore, binding of NF-IL6 (C/EBPbeta) and c-Jun to the SPRR1A promoter was observed after CT-1 stimulation. Histological analysis revealed that SPRR1A induction after mechanical stress of pressure overload was restricted to myocytes surrounding piecemeal necrotic lesions. A similar expression pattern was found in postinfarcted rat hearts. Both in vitro and in vivo ectopic overexpression of SPRR1A protected cardiomyocytes against ischemic injury. Thus, this study identifies SPRR1A as a novel stress-inducible downstream mediator of gp130 cytokines in cardiomyocytes and documents its cardioprotective effect against ischemic stress. 相似文献
80.
Shigekiyo Matsumoto Chihiro Shingu Hironori Koga Satoshi Hagiwara Hideo Iwasaka Takayuki Noguchi Isao Yokoi 《Neurochemical research》2010,35(7):1010-1016
Electron spin resonance (ESR)-silent ascorbate solutions generate a detectable, likely concentration-dependent signal of ascorbyl
free radicals (AFR) immediately upon addition of a molar excess of dimethyl sulfoxide (DMSO). We aimed to perform quantitative
ESR analysis of AFR in real time after addition of DMSO (AFR/DMSO) to evaluate ascorbate concentrations in fresh hippocampus
or plasma following systemic administration of kainate in mice. Use of a special tissue-type quartz cell allowed immediate
detection of AFR/DMSO ESR spectra in fresh tissues from mice. AFR/DMSO content was increased significantly in fresh hippocampus
or plasma obtained during kainate-induced seizures of mice, reaching maximum levels at 90 min after intraperitoneal administration
of 50 mg/kg kainic acid. This suggests that oxidative injury of the hippocampus resulted from the accumulation of large amounts
of ascorbic acid in the brain after kainic acid administration. AFR/DMSO content measured on an ESR spectrometer can be used
for real-time evaluation of ascorbate content in fresh tissue. Due to the simplicity, good performance, low cost and real-time
monitoring of ascorbate, this method may be applied to clinical research and treatment in the future. 相似文献