著者

市橋 伯一

出版者

一般社団法人 日本生物物理学会

雑誌

生物物理 (ISSN:05824052)

巻号頁・発行日

vol.50, no.3, pp.128-129, 2010 (Released:2010-06-09)

参考文献数

6

被引用文献数

1 1

著者

伊藤 耕一 中村 義一

出版者

一般社団法人 日本生物物理学会

雑誌

生物物理 (ISSN:05824052)

巻号頁・発行日

vol.38, no.1, pp.18-20, 1998-01-25 (Released:2009-05-25)

参考文献数

13

著者

今村 博臣 安東 友美 藤川 誠

出版者

一般社団法人 日本生物物理学会

雑誌

生物物理 (ISSN:05824052)

巻号頁・発行日

vol.53, no.1, pp.020-023, 2013 (Released:2013-01-29)

参考文献数

8

---

ATP is indispensable for all living organisms. Despite its importance, however, distribution and dynamics of ATP level inside living cells still remained unclear. We have developed FRET-based ATP biosensors, “ATeam” and “GO-ATeam”, which enabled us to visualize intracellular ATP level. Using these biosensors, we have successfully evaluated the effect of IF1 protein and Ca2+ on regulation of ATP level. Also, we found that replication of hepatitis C virus genome resulted in the declination of cytosolic ATP level of host cells and the formation of putative virus replication sites with high ATP levels.

著者

吉村 仁

出版者

一般社団法人 日本生物物理学会

雑誌

生物物理

巻号頁・発行日

vol.50, no.2, 2010

著者

奥田 覚 井上 康博 安達 泰治

出版者

一般社団法人 日本生物物理学会

雑誌

生物物理 (ISSN:05824052)

巻号頁・発行日

vol.54, no.1, pp.031-034, 2014 (Released:2014-01-29)

参考文献数

9

被引用文献数

2 5

著者

田崎 明 喜多 英治 大塚 仁也

出版者

一般社団法人 日本生物物理学会

雑誌

生物物理 (ISSN:05824052)

巻号頁・発行日

vol.15, no.3, pp.125-132, 1975-05-25 (Released:2009-05-25)

参考文献数

12

被引用文献数

2 3

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In the last decade, SQUID "Superconducting Quantum Interference Device" has been developed in low temperature physics area. The SQUID is a device to which quantum effect in superconductivity is applied, and is used as a high sensitive magnetometer, low level current detector etc.. In this report, basic concepts and applications of this device are reviewed, and then our development on this device for biological measurements is presented. Possibilities of kinetic measurements of some reaction systems are also discussed.

著者

菅瀬 謙治

出版者

一般社団法人 日本生物物理学会

雑誌

生物物理 (ISSN:05824052)

巻号頁・発行日

vol.48, no.5, pp.279-281, 2008 (Released:2008-09-25)

参考文献数

4

被引用文献数

2

著者

佐村 俊和 池谷 裕二 佐藤 能臣

出版者

一般社団法人 日本生物物理学会

雑誌

生物物理 (ISSN:05824052)

巻号頁・発行日

vol.57, no.1, pp.033-035, 2017 (Released:2017-01-26)

参考文献数

9

著者

Shigeki Mitaku Ryusuke Sawada

出版者

一般社団法人 日本生物物理学会

雑誌

Biophysics and Physicobiology (ISSN:21894779)

巻号頁・発行日

vol.13, pp.305-310, 2016 (Released:2016-11-18)

参考文献数

7

被引用文献数

1 5

---

“Life” is a particular state of matter, and matter is composed of various molecules. The state corresponding to “life” is ultimately determined by the genome sequence, and this sequence determines the conditions necessary for survival of the organism. In order to elucidate one parameter characterizing the state of “life”, we analyzed the amino acid sequences encoded in the total genomes of 557 prokaryotes and 40 eukaryotes using a membrane protein prediction online tool called SOSUI. SOSUI uses only the physical parameters of the encoded amino acid sequences to make its predictions. The ratio of membrane proteins in a genome predicted by the SOSUI online tool was around 23% for all genomes, indicating that this parameter is controlled by some mechanism in cells. In order to identify the property of genome DNA sequences that is the possible cause of the constant ratio of membrane proteins, we analyzed the nucleotide compositions at codon positions and observed the existence of systematic biases distinct from those expected based on random distribution. We hypothesize that the constant ratio of membrane proteins is the result of random mutations restricted by the systematic biases inherent to nucleotide codon composition. A new approach to the biological sciences based on the holistic analysis of whole genomes is discussed in order to elucidate the principles underlying “life” at the biological system level.

著者

Takako Sakano Md. Iqbal Mahamood Takefumi Yamashita Hideaki Fujitani

出版者

一般社団法人 日本生物物理学会

雑誌

Biophysics and Physicobiology (ISSN:21894779)

巻号頁・発行日

vol.13, pp.181-194, 2016 (Released:2016-07-14)

参考文献数

39

被引用文献数

45

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The accurate prediction of a ligand–protein complex structure is important for computer-assisted drug development. Although many docking methods have been developed over the last three decades, the success of binding structure prediction remains greatly limited. The purpose of this study was to demonstrate the usefulness of molecular dynamics (MD) simulation in assessing a docking pose predicted using a docking program. If the predicted pose is not unstable in an aqueous environment, MD simulation equilibrates the system and removes the ligand from the predicted position. Here we investigated two proteins that are important potential therapeutic targets: β2 adrenergic receptor (β2AR) and PR-Set7. While β2AR is rigid and its ligands are very similar to the template ligand (carazolol), PR-Set7 is very flexible and its ligands vary greatly from the template ligand (histone H4 tail peptide). On an empirical basis, we usually expect that the docking prediction is accurate when the protein is rigid and its ligands are similar to the template ligand. The MD analyses in this study clearly suggested such a tendency. Furthermore, we discuss the possibility that the MD simulation can predict the binding pose of a ligand.

著者

堀 沢子 西田 宏記

出版者

一般社団法人 日本生物物理学会

雑誌

生物物理 (ISSN:05824052)

巻号頁・発行日

vol.36, no.3, pp.139-143, 1996-05-25 (Released:2009-07-09)

参考文献数

19

---

The cell fate determination in ascidian embryos is mediated by various cell interactions. Two sensory pigment cell precursors constitute an equivalence group, in which the ocellus (eye) pathway is the dominant fate. It is suggested that the unique cell interaction, which is called lateral inhibition, is involved in determination events of these equivalent cells. It is likely that the mode of specification which utilizes the lateral inhibition within equivalent cells plays a fundamental role during early embryogenesis in both invertebrates and vertebrates.

著者

Ichiro Yamato Yoshimi Kakinuma Takeshi Murata

出版者

一般社団法人 日本生物物理学会

雑誌

Biophysics and Physicobiology (ISSN:21894779)

巻号頁・発行日

vol.13, pp.37-44, 2016 (Released:2016-02-27)

参考文献数

39

被引用文献数

8

---

Among the many types of bioenergy-transducing machineries, F- and V-ATPases are unique bio- and nano-molecular rotary motors. The rotational catalysis of F1-ATPase has been investigated in detail, and molecular mechanisms have been proposed based on the crystal structures of the complex and on extensive single-molecule rotational observations. Recently, we obtained crystal structures of bacterial V1-ATPase (A3B3 and A3B3DF complexes) in the presence and absence of nucleotides. Based on these new structures, we present a novel model for the rotational catalysis mechanism of V1-ATPase, which is different from that of F1-ATPases.

著者

Hitomi Komatsu Fumio Hayashi Masahiro Sasa Koji Shikata Shigeru Yamaguchi Keiichi Namba Kenji Oosawa

出版者

一般社団法人 日本生物物理学会

雑誌

Biophysics and Physicobiology (ISSN:21894779)

巻号頁・発行日

vol.13, pp.13-25, 2016 (Released:2016-01-28)

参考文献数

81

被引用文献数

9

---

FliF is the protein comprising the MS-ring of the bacterial flagellar basal body, which is the base for the assembly of flagellar axial structures. From a fliF mutant that easily releases the rod-hook-filament in viscous environments, more than 400 revertants that recovered their swarming ability in viscous conditions, were isolated. The second-site mutations were determined for approximately 70% of them. There were three regions where the mutations were localized: two in Region I, 112 in Region II, and 71 in Region III including the true reversion. In Region I, second-site mutations were found in FlgC and FlgF of the proximal rod, suggesting that they affect the interaction between the MS-ring and the rod. In Region II, there were 69 and 42 mutations in MotA and MotB, respectively, suggesting that the second-site mutations in MotA and MotB may decrease the rotational speed of the flagellar motor to reduce the probability of releasing the rod under this condition. One exception is a mutation in FlhC that caused a down regulation of the flagellar proteins production but it may directly affect transcription or translation of motA and motB. In Region III, there were 44, 24, and 3 mutations in FliG, FliM, and FliF, respectively. There were no second-site mutations identified in FliN although it is involved in torque generation as a component of the C-ring. Many of the mutations were involved in the motor rotation, and it is suggested that such reduced speeds result in stabilizing the filament attachment to the motor.

著者

Yuki Nakamura Kayo Hibino Toshio Yanagida Yasushi Sako

出版者

一般社団法人 日本生物物理学会

雑誌

Biophysics and Physicobiology (ISSN:21894779)

巻号頁・発行日

vol.13, pp.1-11, 2016 (Released:2016-01-20)

参考文献数

30

被引用文献数

12

---

Son of sevenless (SOS) is a guanine nucleotide exchange factor that regulates cell behavior by activating the small GTPase RAS. Recent in vitro studies have suggested that an interaction between SOS and the GTP-bound active form of RAS generates a positive feedback loop that propagates RAS activation. However, it remains unclear how the multiple domains of SOS contribute to the regulation of the feedback loop in living cells. Here, we observed single molecules of SOS in living cells to analyze the kinetics and dynamics of SOS behavior. The results indicate that the histone fold and Grb2-binding domains of SOS concertedly produce an intermediate state of SOS on the cell surface. The fraction of the intermediated state was reduced in positive feedback mutants, suggesting that the feedback loop functions during the intermediate state. Translocation of RAF, recognizing the active form of RAS, to the cell surface was almost abolished in the positive feedback mutants. Thus, the concerted functions of multiple membrane-associating domains of SOS governed the positive feedback loop, which is crucial for cell fate decision regulated by RAS.

著者

Mika Morikawa Rina Naito Koichi Mita Satoshi Watabe Kazunari Nakaishi Teruki Yoshimura Toshiaki Miura Seiichi Hashida Etsuro Ito

出版者

一般社団法人 日本生物物理学会

雑誌

Biophysics and Physicobiology (ISSN:21894779)

巻号頁・発行日

vol.12, pp.79-86, 2015 (Released:2015-11-12)

参考文献数

38

被引用文献数

1 15

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Adiponectin is a hormone secreted from adipocytes, and it demonstrates antidiabetic, anti-atherosclerotic, anti-obesity and anti-inflammatory effects. However, the patterns of change in urinary adiponectin levels in various diseases remain unknown, because only trace amounts of the hormone are present in urine. In the present study, we applied an ultrasensitive ELISA coupled with thio-NAD cycling to measure urinary adiponectin levels. Spike-and-recovery tests using urine confirmed the reliability of our ultrasensitive ELISA. The limit of detection for adiponectin in urine was 2.3×10–19 moles/assay (1.4 pg/mL). The urinary adiponectin concentration ranged between 0.04 and 5.82 ng/mL in healthy subjects. The pilot study showed that the urinary adiponectin levels, which were corrected by the creatinine concentration, were 0.73±0.50 (ng/mg creatinine, N=6) for healthy subjects, versus 12.02±3.85 (ng/mg creatinine, N=3) for patients with diabetes mellitus (DM). That is, the urinary adiponectin levels were higher (P<0.05) in DM patients than in healthy subjects. Further, these urinary adiponectin levels tended to increase with the progression of DM accompanied with nephropathy. Our method is thus expected to provide a simple, rapid and reasonably priced test for noninvasive monitoring of the progression of DM without the requirement of special tools.

著者

石塚 徹 江川 遼 梅田 桂子 東海林 亙 八尾 寛

出版者

一般社団法人 日本生物物理学会

雑誌

生物物理 (ISSN:05824052)

巻号頁・発行日

vol.55, no.6, pp.311-316, 2015 (Released:2015-11-28)

参考文献数

29

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Since the discovery of channelrhodopsins in 2002-2003, the light is now engineered to manipulate physiological states of a cell, a tissue or a body with the progress of three kinds of researches: (1) molecular biology of photoreceptive proteins, (2) cause-effect relationships in the biological system and (3) fabrication of opto-electronics or nanodevices. The near-infrared light, which conveys energy deep into the tissues, is expected to be used for optogenetics with the creation of proteins that change their conformations with such energy or the improvement of nanodevices that transfer the energy to photoreceptive proteins.

著者

川戸 佳

出版者

一般社団法人 日本生物物理学会

雑誌

生物物理 (ISSN:05824052)

巻号頁・発行日

vol.51, no.2, pp.076-079, 2011 (Released:2011-03-30)

参考文献数

8

---

Functions of the hippocampus is dependent on brain-derived-neurosteroids. Because estrogen is synthesized locally in the hippocampus, as well as supplied from the ovary, its functions are attracting much attention. Hippocampal sex-steroids modulate memory-related synaptic plasticity not only slowly but also rapidly. Slow actions of estradiol (E2) occur via nuclear receptors (ERα), while rapid E2 actions occur via synapse-localized ERα. Elevation or decrease of the E2 concentration changes rapidly the density and morphology of spines. Kinase networks are involved downstream of ERα. The long-term depression is modulated rapidly by changes of E2 level. The E2 level is much higher than that in blood circulation. Hippocampus-derived sex-steroids play a major role in modulation of synaptic plasticity.

著者

山下 高廣

出版者

一般社団法人 日本生物物理学会

雑誌

生物物理 (ISSN:05824052)

巻号頁・発行日

vol.51, no.4, pp.186-187, 2011 (Released:2011-07-25)

参考文献数

6

被引用文献数

1

著者

箱嶋 敏雄 平野 良憲 村瀬 浩司 Sun Tai-ping

出版者

一般社団法人 日本生物物理学会

雑誌

生物物理 (ISSN:05824052)

巻号頁・発行日

vol.49, no.4, pp.200-201, 2009 (Released:2009-07-25)

参考文献数

10

著者

太和田 勝久

出版者

一般社団法人 日本生物物理学会

雑誌

生物物理 (ISSN:05824052)

巻号頁・発行日

vol.41, no.5, pp.221-221, 2001 (Released:2001-09-29)