著者
有吉 眞理子 白川 昌宏
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.3, pp.124-127, 2011 (Released:2011-05-25)
参考文献数
19

DNA methylation is a heritable epigenetic mark that enables the tissue-specific gene expression accompanied by modulation of chromatin structure. Interpretation and maintenance of DNA methylation pattern on genome are crucial for a wide range of biological processes such as genomic imprinting, embryogenesis and carcinogenesis. Recent crystallographic studies of methylated DNA binding proteins have provided a new insight into the molecular mechanisms underlying epigenetic regulation. This review focuses on a structure basis for strict recognition of the methylation status of the CpG site by DNA binding domains in MBD family proteins and UHRF1.
著者
津下 英明
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.43, no.4, pp.168-173, 2003 (Released:2003-07-23)

The family of mono-ADP-ribosyltransferase includes not only bacterial toxins but also mammalian enzymes. Recently, crystal structures of arginine-specific ADP-ribosyltransferase have been revealed, giving a better understanding of type IV toxin. They are VIP2 from Bacillus and Ia from Clostridium perfringens. VIP2 and Ia ADP-ribosylate the Arg177 of actin. They consist of topologically similar N- and C-domains, which have not been expected from the amino acid sequence. C-domain is an enzymatic domain. N-domain interacts with VIP1 and Ib, respectively. C-domain structures were basically the same but the surface charge of N-domain was found significantly different between VIP2 and Ia. Rat ART2.2 and rho-targeted C3 toxin(asparagine-specific)consist of only one domain and the structure is similar to the C-domain of Ia. We summarize the crystal structure and the reaction mechanism of Ia.
著者
畠山 哲央 金子 邦彦
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.4, pp.186-190, 2017 (Released:2017-07-28)
参考文献数
20

Robustness and plasticity are important characteristics common to a variety of biological systems and have attracted much attention not only from biologists but also from physicists interested in biosystems. Whereas robustness concerns insensitivity to perturbations against external changes, plasticity concerns changeability upon external inputs. How these two properties are compatible with each other is an important question to be addressed. Recently we have uncovered universal reciprocity relationship between the robustness of period and plasticity of phase in biochemical oscillators such as circadian clocks. We review this relationship and discuss its theoretical origin and biological relevance.
著者
伊藤(新澤) 恭子 村本 和優
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.60, no.5, pp.276-279, 2020 (Released:2020-09-30)
参考文献数
19

Cytochrome c oxidase in the mitochondrial respiratory chain mostly exists as an independent monomer, or as a monomer associated with the complexes I and III in the supercomplex, although its molecular mechanism has been elucidated based on the crystal structure of its dimeric form. Here, we report detailed comparison of the activity and crystal structure between the monomer and the dimer, and the possibility that the monomer is an activated form, whereas the dimer can be regarded as a physiological standby form in the mitochondrial membrane.
著者
末次 正幸
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.60, no.5, pp.284-287, 2020 (Released:2020-09-30)
参考文献数
15

In vitro reconstitution of cellular events is a promising strategy as a bottom-up approach to build an artificial cell in the field of synthetic biology. Also, the reconstituted system sometimes provides a useful biotechnology tool for various fields. We recently reconstituted a whole replication cycle of the Escherichia coli chromosome in vitro as a part of the bottom-up synthetic biology. This replication cycle reaction (RCR) propagates circular DNA exponentially and precisely by autonomous repetition of the cycle in an isothermal reaction. Even genome-sized DNA (1 Mbp) can be propagated as circular DNA in RCR. We also developed a DNA assembly tool. The combination of the DNA assembly and RCR amplification enables cell-free synthesis of artificial large circular DNA, providing a powerful tool for a top-down study of the synthetic biology, in which living cells are modified at a whole genome level.
著者
辰巳 仁史 早川 公英 曽我部 正博
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.4, pp.187-191, 2015 (Released:2015-07-31)
参考文献数
19

Intracellular and extracellular mechanical forces affect the dynamics of actin cytoskeletons, however, the underlying biophysical mechanisms how forces are transduced into changes in the actin dynamics remain largely unknown. We find that activity of the actin severing protein ADF/cofilin negatively depends on tension in the actin filament through tension-dependent binding/unbinding of cofilin to/from the actin filament, thereby relaxed actin filaments are severed whereas tensed ones are not. Here we review the latest knowledge on this phenomenon and discuss its biological impact.
著者
高田 彰二
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.4, pp.158-159, 2010 (Released:2010-07-25)
被引用文献数
1 1
著者
堀尾 修平
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.6, pp.290-293, 2010 (Released:2010-11-25)
参考文献数
18

There exist several cross talks between histamine H1 receptor and other types of receptor, especially in their effects on H1 receptor expression. Muscarinic, IL-4, and H1 receptor stimulation increases (up-regulates) H1 receptor level through the activation of H1 receptor gene transcription, whereas β2-adrenergic receptor stimulation decreases (down-regulates) H1 receptors through degradation of H1 receptor proteins and the inhibition of H1 receptor gene transcription. This review describes the significance of these cross talks in regulating the H1 receptor level and discusses their physiological and pathophysiological roles.
著者
永山 國昭
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.4, pp.196-200, 2001 (Released:2001-08-10)

Physics of protein folding developed by late Toyoichi Tanaka, who offered his devotion to breaking the life's second code, is described and its significance to the thermodynamical law in nature and evolution is studied. Particularly his extended formalism for canonical emsemble dedicated to overcome the very different time-scales characterizing protein folding and evolution is discussed.
著者
早野 順一郎 山田 眞己 藤浪 隆夫 横山 清子 渡辺 與作 高田 和之
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.28, no.4, pp.198-202, 1988-07-25 (Released:2009-05-25)
参考文献数
10
被引用文献数
9 11

Method for spectral analysis of heart rate variability (HRV), and physiological characteristics of their spectral components are discussed. Respiratory component has a liner relationship with cardiac parasympathetic activity. Other component ranging around 0.1Hz is related to Mayer wave of arterial blood pressure. They provide a quantitative index of autonomic nervous function.