ミトコンドリア病根治薬を目指した塩基配列選択的DNA結合性化合物の開発

京都大学新制・課程博士博士(理学)甲第23034号理博第4711号新制||理||1675(附属図書館)京都大学大学院理学研究科化学専攻(主査)教授 杉山 弘, 教授 深井 周也, 教授 秋山 芳展学位規則第4条第1項該当Doctor of ScienceKyoto UniversityDGA

Chiral anomaly in a (1+1)-dimensional Floquet system under high-frequency electric fields

We investigate the chiral anomaly in a Floquet system under a time-periodic electric field in (1+1) dimensions. Using the van~Vleck high-frequency expansion, we analytically calculate the chiral current and the pseudo-scalar condensate for massless/massive fermions and how they are balanced with the topological charge. In the high-frequency limit, we find that finite-mass effects are suppressed and the topological charge is dominated by the chirality production. Our calculations show that the information about the chiral anomaly is stored not in the static Floquet Hamiltonian but in the periodic kick operator. The computational steps are useful as the theoretical foundation for higher-dimensional generalization.Comment: 29 pages; v2: minor changes, to appear in Annals of Physic

Mitochondria and G-quadruplex evolution: an intertwined relationship

G-quadruplexes (G4s) are non-canonical structures formed in guanine (G)-rich sequences through stacked G tetrads by Hoogsteen hydrogen bonding. Several studies have demonstrated the existence of G4s in the genome of various organisms, including humans, and have proposed that G4s have a regulatory role in various cellular functions. However, little is known regarding the dissemination of G4s in mitochondria. In this review, we report the observation that the number of potential G4-forming sequences in the mitochondrial genome increases with the evolutionary complexity of different species, suggesting that G4s have a beneficial role in higher-order organisms. We also discuss the possible function of G4s in mitochondrial (mt)DNA and long noncoding (lnc)RNA and their role in various biological processes

SYNTHESIS OF NIGRICANIN VIA INTRAMOLECULAR BIARYL COUPLING REACTION OF FUNCTIONALIZED PHENYL BENZOATE

A tetracyclic natural product, nigricanin (1), was synthesized through an intramolecular biaryl coupling reaction of the phenyl benzoate derivative which was derived from the corresponding phenol and benzoic acid

Dynamic Analysis of Photosynthate Translocation Into Strawberry Fruits Using Non-invasive 11C-Labeling Supported With Conventional Destructive Measurements Using 13C-Labeling

In protected strawberry (Fragaria × ananassa Duch.) cultivation, environmental control based on the process of photosynthate translocation is essential for optimizing fruit quality and yield, because the process of photosynthate translocation directly affects dry matter partitioning. We visualized photosynthate translocation to strawberry fruits non-invasively with 11CO2 and a positron-emitting tracer imaging system (PETIS). We used PETIS to evaluate real-time dynamics of 11C-labeled photosynthate translocation from a 11CO2-fed leaf, which was immediately below the inflorescence, to individual fruits on an inflorescence in intact plant. Serial photosynthate translocation images and animations obtained by PETIS verified that the 11C-photosynthates from the source leaf reached the sink fruit within 1 h but did not accumulate homogeneously within a fruit. The quantity of photosynthate translocation as represented by 11C radioactivity varied among individual fruits and their positions on the inflorescence. Photosynthate translocation rates to secondary fruit were faster than those to primary or tertiary fruits, even though the translocation pathway from leaf to fruit was the longest for the secondary fruit. Moreover, the secondary fruit was 25% smaller than the primary fruit. Sink activity (11C radioactivity/dry weight [DW]) of the secondary fruit was higher than those of the primary and tertiary fruits. These relative differences in sink activity levels among the three fruit positions were also confirmed by 13C tracer measurement. Photosynthate translocation rates in the pedicels might be dependent on the sink strength of the adjoining fruits. The present study established 11C-photosynthate arrival times to the sink fruits and demonstrated that the translocated material does not uniformly accumulate within a fruit. The actual quantities of translocated photosynthates from a specific leaf differed among individual fruits on the same inflorescence. To the best of our knowledge, this is the first reported observation of real-time translocation to individual fruits in an intact strawberry plant using 11C-radioactive- and 13C-stable-isotope analyses

人総研シンポジウム抄録 : 福島原発事故12年の経験から学ぶ -当時小学生だった若者達との対話から(第2回)-

departmental bulletin pape

Chemical Approaches to the Development of Artificial Transcription Factors Based on Pyrrole‐Imidazole Polyamides

To maintain the functions of living organisms, cells have developed complex gene regulatory networks. Transcription factors have a central role in spatiotemporal control of gene expression and this has motivated us to develop artificial transcription factors that mimic their function. We found that three functions could be mimicked by applying our chemical approaches: i) efficient delivery into organelles that contain target DNA, ii) specific DNA binding to the target genomic region, and iii) regulation of gene expression by interaction with other transcription coregulators. We chose pyrrole-imidazole polyamides (PIPs), sequence-selective DNA binding molecules, as DNA binding domains, and have achieved each of the required functions by introducing other functional moieties. The developed artificial transcription factors have potential as chemical tools that can be used to artificially modulate gene expression to enable cell fate control and to correct abnormal gene regulation for therapeutic purposes

First record of a known-age juvenile loggerhead turtle (Caretta caretta) at the Sanriku Coast in the Northwest Pacific Ocean

Loggerhead turtles (Caretta caretta) in the North Pacific Ocean are primarily born in the southern coast of the Japanese Archipelago. After a developmental period of several years in Central and East Pacific Oceans, they re-migrate to Japanese waters at a larger juvenile stage. However, the exact duration until re-migrating to Japanese waters is not known because of methodological limitations of current age estimation among wild sea turtles. On 27 August 2018, a juvenile loggerhead turtle (straight carapace length: 60.8 cm, body mass: 35.0 kg) with a passive integrated transponder (PIT) tag was incidentally captured by a set net at the Sanriku Coast, Northeastern Japan (39°22′21″N, 141°58′41″E). The PIT tag number revealed that it is a 10-year old turtle born in Yakushima Island (30°24′21″N, 130°25′58″E) in 2008. Total 1,095 loggerhead hatchlings with PIT tags were released from Yakushima Island in 2008. To the best of our knowledge, this is the first record of a known-age and non-head started loggerhead turtle in the North Pacific population. The tagged loggerhead turtle provides important knowledge about the pelagic stage duration of this species in the North Pacific population