Alternative method for determining leaf CO2 assimilation without gas exchange measurements: Performance, comparison and sensitivity analysis.

We present an alternative method to determine leaf CO2 assimilation rate (An ), eliminating the need for gas exchange measurements in proximal and remote sensing. This method combines the Farquhar-von Caemmerer-Berry photosynthesis model with mechanistic light reaction (MLR) theory and leaf energy balance (EB) analysis. The MLR theory estimates the actual electron transport rate (J) by leveraging chlorophyll fluorescence via pulse amplitude-modulated fluorometry for proximal sensing or sun-induced chlorophyll fluorescence measurements for remote sensing, along with spectral reflectance. The EB equation is used to directly estimate stomatal conductance from leaf temperature. In wheat and soybean, the MLR-EB model successfully estimated An variations, including midday depression, under various environmental and phenological conditions. Sensitivity analysis revealed that the leaf boundary layer conductance (gb ) played an equal, if not more, crucial role compared to the variables for J. This was primarily caused by the indirect influence of gb through the EB equation rather than its direct impact on convective CO2 exchange on the leaf. Although the MLR-EB model requires an accurate estimation of gb , it can potentially reduce uncertainties and enhance applicability in photosynthesis assessment when gas exchange measurements are unavailable.

2D-3D-Convertible, pH-Responsive Lipid Nanosheets.

2D nanosheets self-assembled with amphiphilic molecules are promising tools for biomedical applications; yet, there are challenges to form and stabilize these nanosheets under complex physiological conditions. Here, the development of lipid nanosheets with high structural stability that can be reversibly converted to cell-sized vesicles by changes in pH within the physiological range robustly, are described. The system is controlled by the membrane disruptive peptide E5 and a cationic copolymer anchored on lipid membranes. It is envisioned that nanosheets formed using the dual anchoring peptide/cationic copolymer system can be employed in dynamic lipidic nanodevices, such as the vesosomes described here, drug delivery systems, and artificial cells.

A Cationic Copolymer Enhances Responsiveness and Robustness of DNA Circuits.

Toehold-mediated DNA circuits are extensively employed to construct diverse DNA nanodevices and signal amplifiers. However, operations of these circuits are slow and highly susceptive to molecular noise such as the interference from bystander DNA strands. Herein, this work investigates the effects of a series of cationic copolymers on DNA catalytic hairpin assembly, a representative toehold-mediated DNA circuit. One copolymer, poly(L -lysine)-graft-dextran, significantly enhances the reaction rate by 30-fold due to its electrostatic interaction with DNA. Moreover, the copolymer considerably alleviates the circuit's dependency on the length and GC content of toehold, thereby enhancing the robustness of circuit operation against molecular noise. The general effectiveness of poly(L -lysine)-graft-dextran is demonstrated through kinetic characterization of a DNA AND logic circuit. Therefore, use of a cationic copolymer is a versatile and efficient approach to enhance the operation rate and robustness of toehold-mediated DNA circuits, paving the way for more flexible design and broader application.

Programmed Control of Fluorescence Blinking Patterns based on Electron Transfer in DNA.

Fluorescence imaging uses changes in the fluorescence intensity and emission wavelength to analyze multiple targets simultaneously. To increase the number of targets that can be identified simultaneously, fluorescence blinking can be used as an additional parameter. To understand and eventually control blinking, we used DNA as a platform to elucidate the processes of electron transfer (ET) leading to blinking, down to the rate constants. With a fixed ET distance, various blinking patterns were observed depending on the DNA sequence between the donor and acceptor units of the DNA platform. The blinking pattern was successfully described with a combination of ET rate constants. Therefore, molecules with various blinking patterns can be developed by tuning ET. It is expected that the number of targets that can be analyzed simultaneously will increase by the power of the number of blinking patterns.

Ribosome binding protein GCN1 regulates the cell cycle and cell proliferation and is essential for the embryonic development of mice.

Amino acids exert many biological functions, serving as allosteric regulators and neurotransmitters, as constituents in proteins and as nutrients. GCN2-mediated phosphorylation of eukaryotic initiation factor 2 alpha (elF2α) restores homeostasis in response to amino acid starvation (AAS) through the inhibition of the general translation and upregulation of amino acid biosynthetic enzymes and transporters by activating the translation of Gcn4 and ATF4 in yeast and mammals, respectively. GCN1 is a GCN2-binding protein that possesses an RWD binding domain (RWDBD) in its C-terminus. In yeast, Gcn1 is essential for Gcn2 activation by AAS; however, the roles of GCN1 in mammals need to be established. Here, we revealed a novel role of GCN1 that does not depend on AAS by generating two Gcn1 mutant mouse lines: Gcn1-knockout mice (Gcn1 KO mice (Gcn1-/-)) and RWDBD-deleted mutant mice (Gcn1ΔRWDBD mice). Both mutant mice showed growth retardation, which was not observed in the Gcn2 KO mice, such that the Gcn1 KO mice died at the intermediate stage of embryonic development because of severe growth retardation, while the Gcn1ΔRWDBD embryos showed mild growth retardation and died soon after birth, most likely due to respiratory failure. Extension of pregnancy by 24 h through the administration of progesterone to the pregnant mothers rescued the expression of differentiation markers in the lungs and prevented lethality of the Gcn1ΔRWDBD pups, indicating that perinatal lethality of the Gcn1ΔRWDBD embryos was due to simple growth retardation. Similar to the yeast Gcn2/Gcn1 system, AAS- or UV irradiation-induced elF2α phosphorylation was diminished in the Gcn1ΔRWDBD mouse embryonic fibroblasts (MEFs), suggesting that GCN1 RWDBD is responsible for GCN2 activity. In addition, we found reduced cell proliferation and G2/M arrest accompanying a decrease in Cdk1 and Cyclin B1 in the Gcn1ΔRWDBD MEFs. Our results demonstrated, for the first time, that GCN1 is essential for both GCN2-dependent stress response and GCN2-independent cell cycle regulation.

Single-Molecule Study of Redox Reaction Kinetics by Observing Fluorescence Blinking.

Recent advances in fluorescence microscopy allow us to track chemical reactions at the single-molecule level. Single-molecule measurements make it possible to minimize the amount of sample needed for analysis and diagnosis. Signal amplification is often applied to ultralow-level biomarker detection. Polymerase chain reaction (PCR) is used to detect DNA/RNA, and enzyme-linked immunosorbent assay (ELISA) can sensitively probe antigen-antibody interactions. While these techniques are brilliant and will continue to be used in the future, single-molecule-level measurements would allow us to reduce the time and cost needed to amplify signals.The kinetics of chemical reactions have been studied mainly using ensemble-averaged methods. However, they can hardly distinguish time-dependent fluctuations and static heterogeneity of the kinetics. The information hidden in ensemble-averaged measurements would be extractable from a single-molecule experiment. Thus, single-molecule measurement would provide unique opportunities to investigate unrevealed phenomena and to elucidate the questions in chemistry, physics, and life sciences. Redox reaction, which is triggered by electron transfer, is among the most fundamental and ubiquitous chemical reactions. The redox reaction of a fluorescent molecule results in the formation of radical ions, which are normally nonemissive. In single-molecule-level measurements, the redox reaction causes the fluctuation of fluorescence signals between the bright ON-state and the dark OFF-state, in a phenomenon called blinking. The duration of the OFF-state (τOFF) corresponds to the lifetime of the radical ion state, and its reaction kinetics can be measured as 1/τOFF. Thus, the kinetics of redox reactions of fluorescent molecules can be accessed at the single-molecule level by monitoring fluorescence blinking. One of the key aspects of single-molecule analysis based on blinking is its robustness. A blinking signal with a certain regular pattern enables single fluorescent molecules to be distinguished and resolved from the random background signal.In this Account, we summarize the recent studies on the single-molecule measurement of redox reaction kinetics, with a focus on our group's recent progress. We first introduce the control of redox blinking to increase the photostability of fluorescent molecules. We then demonstrate the control of redox blinking, which allows us to detect target DNA by monitoring the function of a molecular beacon-type probe, and we investigate antigen-antibody interactions at the single-molecule level. By tracing the time-dependent changes in blinking patterns, redox blinking is shown to be adaptable to tracking the structural switching dynamics of RNA, the preQ1 riboswitch. This Account ends with a discussion of our ongoing work on the control of fluorescent blinking. We also discuss the development of devices that allow single-molecule-level analysis in a high-throughput fashion.

Smart Protein Refolding System Based on UCST-Type Ureido Polymers.

We have reported that ureido polymers exhibit upper critical solution temperature (UCST)-type phase behavior in solution, which is the opposite of lower critical solution temperature (LCST)-type behavior. Furthermore, UCST-type ureido polymers undergo liquid-liquid phase separation (LLPS) upon cooling rather than the liquid-solid phase transition of the typical LCST-type polymers. In this study, ureido polymers with hydrophobic groups were prepared to evaluate the effects of cooling-induced LLPS of UCST-type polymers on refolding of proteins. When protein was heated with a ureido polymer functionalized with undecyl groups, aggregation of the protein was prevented. Subsequent cooling incubation resulted in the spontaneous release of the protein from the polymer. The released protein had enzymatic activity, suggesting that the protein refolded properly. Interestingly, efficient refolding was observed when the solution of the UCST-type ureido polymer and protein was incubated at around the phase separation temperature of the polymer, implying that cooling-induced LLPS of the polymer enhanced the release of the protein. Additionally, by centrifugation at 4 °C, the refolded protein was readily separated from the ureido polymers, which precipitated upon cooling.

Comprehensive analyses of the cysteine thiol oxidation of PKM2 reveal the effects of multiple oxidation on cellular oxidative stress response.

Redox regulation of proteins via cysteine residue oxidation is involved in the control of various cellular signal pathways. Pyruvate kinase M2 (PKM2), a rate-limiting enzyme in glycolysis, is critical for the metabolic shift from glycolysis to the pentose phosphate pathway under oxidative stress in cancer cell growth. The PKM2 tetramer is required for optimal pyruvate kinase (PK) activity, whereas the inhibition of inter-subunit interaction of PKM2 induced by Cys358 oxidation has reduced PK activity. In the present study, we identified three oxidation-sensitive cysteine residues (Cys358, Cys423 and Cys424) responsible for four oxidation forms via the thiol oxidant diamide and/or hydrogen peroxide (H2O2). Possibly due to obstruction of the dimer-dimer interface, H2O2-induced sulfenylation (-SOH) and diamide-induced modification at Cys424 inhibited tetramer formation and PK activity. Cys423 is responsible for intermolecular disulfide bonds with heterologous proteins via diamide. Additionally, intramolecular polysulphide linkage (-Sn-, n ≧ 3) between Cys358 and an unidentified PKM2 Cys could be induced by diamide. We observed that cells expressing the oxidation-resistant PKM2 (PKM2C358,424A) produced more intracellular reactive oxygen species (ROS) and exhibited greater sensitivity to ROS-generating reagents and ROS-inducible anti-cancer drugs compared with cells expressing wild-type PKM2. These results highlight the possibility that PKM2 inhibition via Cys358 and Cys424 oxidation contributes to eliminating excess ROS and oxidative stress.

Control of Triplet Blinking Using Cyclooctatetraene to Access the Dynamics of Biomolecules at the Single-Molecule Level.

To explore the dynamics of biomolecules, tracing the kinetics of photo-induced chemical reactions via the triplet excited state (T1 ) of probe molecules offers a timescale that is about 106 times wider than via the singlet excited state (S1 ). Using cyclooctatetraene (COT) as a triplet energy acceptor and at the same time as a photostabilizer, the triplet-triplet energy transfer (TTET) kinetics governed by oligonucleotide (oligo) dynamics were studied at the single-molecule level by measuring fluorescence blinking. TTET kinetics measurement allowed us to access the length- and sequence-dependent dynamics of oligos and realize the single-molecule detection of a model microRNA biomarker. In sharp contrast to the singlet-singlet Förster resonance energy transfer (FRET) that occurs in the 1-10 nm range, TTET requires a Van der Waals contact. The present method is thus a complementary method to FRET and provides direct information on biomolecular dynamics on the µs to ms timescale.

Kinetics of Photoinduced Reactions at the Single-Molecule Level: The KACB Method.

The kinetics of photoinduced reactions can be approached by laser flash photolysis techniques. Although such techniques allow for a detailed understanding of the important photophysics of molecules, they normally require a substantial amount of sample for measurements (>1 nmol), and thus, they are difficult to apply to analytical and diagnostic applications. The photophysics of a fluorescent molecule can be accessed by monitoring the kinetics of the fluctuation of fluorescence, which is called blinking. Blinking is a phenomenon that can be monitored only if molecules are observed at the single-molecule level. In bulk solution, blinking kinetics can be measured by using fluorescence correlation spectroscopy (FCS), which normally requires more than 105 times less sample than that required for laser flash photolysis. Blinking is controlled to extract fruitful microenvironmental information around a fluorescent molecule, by using a method named kinetic analysis based on the control of fluorescence blinking (KACB). This Concept highlights the adaption of the KACB method to investigate the local conformation of DNA with less than 1 pmol of DNA sample.

Isotope analysis reveals proportional change and site-selection variation of river- and lake-produced eggs of a landlocked migratory fish.

Changes in the proportions of river- and lake-produced eggs of a landlocked amphidromous fish, ayu (Plecoglossus altivelis altivelis) in the Lake Biwa water system, Japan, were monitored by stable isotope analysis, based on different δ15 N and δ13 C values of prey organisms between the lake and its tributaries. During the 3 month reproduction season, the δ15 N values of spawned eggs decreased with time. This result implies that there was a shift from lake-produced eggs to river-produced eggs within a reproductive season, based on the observation that adult fish in the lake had previously been shown to have eggs with distinctly higher δ15 N values in their ovaries than those in the tributaries. This explanation was also supported by the change in δ13 C values of the spawned eggs. Furthermore, eggs with lower δ15 N and higher δ13 C values tended to be spawned at less variable depths, suggesting that females spawning river-produced eggs selected the spawning sites from a narrower range. We conclude that stable isotope ratios of spawned eggs can be indicators of the relative contributions of different food chains and can enable comparisons of reproductive characteristics between types of egg.

[Case of Asymptomatic Multiple Bone and Bone Marrow Metastases in Gastric Signet-Ring Cell Carcinoma].

A 57-year-old man visited our hospital for evaluation of an abnormal shadow identified on chest radiography. Chest computed tomography findings suggested diffuse bone metastases in the thoracic spine and the bilateral ribs. Notably, 18- fluoro-deoxyglucose positron emission tomography revealed no evidence of the primary tumor. Esophagogastroduodenoscopy revealed a small flat depressed lesion in the greater curvature of the gastric angle. Histopathological examination of this specimen revealed a signet-ring cell carcinoma. Histopathological examination of a biopsy obtained from the right iliac bone revealed a signet-ring cell carcinoma similar to that observed in the gastric mucosa. He was diagnosed with a gastric signetring cell carcinoma with multiple bone and bone marrow metastases. Cervical metastases caused gradual worsening of respiratory functions, necessitating artificial ventilation. He died of sudden ventricular tachycardia on the 36th day. Clinicians should be aware of the features of primary gastric cancer with bone and bone marrow metastases for early diagnosis and prompt treatment.

Highly Ordered Polypeptide with UCST Phase Separation Behavior.

Manipulating phase separation structures of thermoresponsive polymers will enhance the usefulness of structure-controllable materials in fields such as drug delivery and tissue engineering. However, behaviors of upper critical solution temperature (UCST) have been less investigated so far, despite the importance of UCST. Here, we examined two citrulline-based polypeptides, poly(d-ornithine- co-d-citrulline) (PdOC) and poly(dl-ornithine- co-dl-citrulline) (PdlOC), to investigate how stereoregularity of the polypeptides influences UCST behavior, in addition to poly(l-ornithine- co-l-citrulline) (PlOC) previously studied. Homochiral PlOC and PdOC showed phase separation temperatures ( Tps) higher than that of racemic PdlOC. Moreover, PdlOC underwent liquid to coacervate phase separation at Tp, whereas PlOC and PdOC underwent liquid to solid-like aggregation transitions. From a structural point of view, circular dichroism and small-angle X-ray scattering measurements revealed that homochiral PlOC and PdOC polypeptides formed α-helical structures and assembled into a regular hexagonal lattice upon phase separation. Interactions between the pendent ureido groups of homochiral POCs appear to play pivotal roles in helical folding and assembly into the hexagonal structure. In addition, Tp change in response to biodegradation was confirmed for both PlOC and PdlOC. The biodegradability was considerably influenced by phase-separated structures. These findings of UCST-type POCs in this study would provide important insights into structure-controllable and thermoresponsive biomaterials.

Liposome-Surface-Initiated ARGET ATRP: Surface Softness Generated by "Grafting from" Polymerization.

Liposomes are self-assembled vesicles of amphiphilic lipid molecules, which have been investigated as models of cells, or tools for drug delivery systems. In these systems, the surface property of the liposomes plays an important role. In this study, we demonstrated a novel polymer modification of liposome surfaces using a controlled radical polymerization, "activators regenerated by electron transfer for atom transfer radical polymerization", in aqueous media without a deoxygenation step. Dynamic light scattering and 1H NMR measurement indicated the successful modification of the polymer on the liposome surface. The molecular weight of the grafted polymer chain was systematically controlled by changing the monomer concentrations in the "grafting from" polymerization. Moreover, the modification resulted in a notable increase in surface softness as indicated by electrophoretic behavior, which was comparable to the surface of cells. The preparation method and the characterization presented in this study would be a helpful guideline in designing the polymer/liposome hybrid having target surface properties.

Synthesis and Properties of Upper Critical Solution Temperature Responsive Nanogels.

A random copolymer ((U/A10)165) bearing pendent ureido groups and a small amount (10 mol %) of primary amino groups exhibits an upper critical solution temperature (UCST). We prepared a diblock copolymer (PMPC20P(U/A10)165) composed of water-soluble poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) and (U/A10)165 blocks via reversible addition-fragmentation chain-transfer radical polymerization with postmodification reaction. The subnumbers are the degrees of polymerization of each block. Although in water PMPC20P(U/A10)165 dissolves as a unimer above the UCST phase transition temperature ( Tp), it forms polymer micelles composed of dehydrated (U/A10)165 cores and hydrophilic PMPC shells. A nanogel was prepared by cross-linking the pendent primary amines in the micelle core using (hydroxymethyl)phosphonium chloride below Tp. NMR and light-scattering data indicated that the nanogel core shrinks upon dehydration below Tp and swells upon hydration above Tp. The nanogel can encapsulate guest molecules such as hydrophobic fluorescence probes and bovine serum albumin (BSA) below Tp mainly owing to hydrophobic interactions in the core. Encapsulated BSA can be held in the nanogel core below Tp and subsequently released above Tp.

Specialized movement and laterality of fin-biting behaviour in Genyochoromis mento in Lake Malawi.

Several vertebrates, including fish, exhibit behavioural laterality and associated morphological asymmetry. Laterality may increase individual fitness as well as foraging strength, accuracy and speed. However, little is known about which behaviours are affected by laterality or what fish species exhibit obvious laterality. Previous research on the predatory behaviour of the scale-eating Lake Tanganyika cichlid Perissodus microlepis indicates behavioural laterality that reflects asymmetric jaw morphology. The Lake Malawi cichlid Genyochromis mento feeds on the fins of other fish, a behaviour that G. mento developed independently from the Tanganyikan Perissodini scale eaters. We investigated stomach contents and behavioural laterality of predation in aquarium to clarify the functional roles and evolution of laterality in cichlids. We also compared the behavioural laterality and mouth asymmetry of G. mento and P. microlepis The diet of G. mento mostly includes fin fragments, but also scales of several fish species. Most individual G. mento specimens showed significant attack bias favouring the skew mouth direction. However, there was no difference in success rate between attacks from the preferred side and those from the non-preferred side, and no lateralized kinetic elements in predation behaviour. Genyochromismento showed weaker laterality than P. microlepis, partly because of their different feeding habits, the phylogenetic constraints from their shorter evolutionary history and their origin from ancestor Haplochromini omnivorous/herbivorous species. Taken together, this study provides new insights into the functional roles of behavioural laterality: predatory fish aiming for prey that show escape behaviours frequently exhibit lateralized behaviour in predation.

Concomitant Nrf2- and ATF4-activation by Carnosic Acid Cooperatively Induces Expression of Cytoprotective Genes.

: Carnosic acid (CA) is a phytochemical found in some dietary herbs, such as Rosmarinus officinalis L., and possesses antioxidative and anti-microbial properties. We previously demonstrated that CA functions as an activator of nuclear factor, erythroid 2 (NF-E2)-related factor 2 (Nrf2), an oxidative stress-responsive transcription factor in human and rodent cells. CA enhances the expression of nerve growth factor (NGF) and antioxidant genes, such as HO-1 in an Nrf2-dependent manner in U373MG human astrocytoma cells. However, CA also induces NGF gene expression in an Nrf2-independent manner, since 50 µM of CA administration showed striking NGF gene induction compared with the classical Nrf2 inducer tert-butylhydroquinone (tBHQ) in U373MG cells. By comparative transcriptome analysis, we found that CA activates activating transcription factor 4 (ATF4) in addition to Nrf2 at high doses. CA activated ATF4 in phospho-eIF2α- and heme-regulated inhibitor kinase (HRI)-dependent manners, indicating that CA activates ATF4 through the integrated stress response (ISR) pathway. Furthermore, CA activated Nrf2 and ATF4 cooperatively enhanced the expression of NGF and many antioxidant genes while acting independently to certain client genes. Taken together, these results represent a novel mechanism of CA-mediated gene regulation evoked by Nrf2 and ATF4 cooperation.

Past history of hepatocellular carcinoma is an independent risk factor of treatment failure in patients with chronic hepatitis C virus infection receiving direct-acting antivirals.

Direct-acting antiviral (DAA) treatment can achieve a high sustained virological response (SVR) rate in patients with hepatitis C virus (HCV) infection regardless of a history of hepatocellular carcinoma (HCC [+]). We examined 838 patients (370 men, median age: 69 years) who were treated with DAAs for comparisons of clinical findings between 79 HCC (+) (9.4%) and 759 HCC (-) (90.6%) patients and associations with treatment outcome. Male frequency was significantly higher in the HCC (+) group (60.8% vs 42.4%, P = 0.006). There were significant differences between the HCC (+) and HCC (-) groups for platelet count (115 vs 152 ×109 /L, P < 0.001), baseline alpha fetoprotein (AFP) (9.9 vs 4.5 ng/mL, P < 0.001) and the established fibrosis markers of FIB-4 index (4.7 vs 3.0, P < 0.001), AST-to-platelet ratio index (APRI) (1.1 vs 0.7, P = 0.009), M2BPGi (3.80 vs 1.78 COI, P < 0.001) and autotaxin (1.91 vs 1.50 mg/L, P < 0.001). The overall SVR rate was 94.7% and significantly lower in the HCC (+) group (87.3 vs 95.5%, P = 0.001). Multivariate analysis revealed that a history of HCC was independently associated with DAA treatment failure (odds ratio: 3.56, 95% confidence interval: 1.32-9.57, P = 0.01). In conclusion, patients with chronic HCV infection and prior HCC tended to exhibit more advanced disease progression at DAA commencement. HCC (+) status at the initiation of DAAs was significantly associated with adverse therapeutic outcomes. DAA treatment for HCV should therefore be started as early as possible, especially before complicating HCC.

Increasing canopy photosynthesis in rice can be achieved without a large increase in water use-A model based on free-air CO2 enrichment.

Achieving higher canopy photosynthesis rates is one of the keys to increasing future crop production; however, this typically requires additional water inputs because of increased water loss through the stomata. Lowland rice canopies presently consume a large amount of water, and any further increase in water usage may significantly impact local water resources. This situation is further complicated by changing the environmental conditions such as rising atmospheric CO2 concentration ([CO2 ]). Here, we modeled and compared evapotranspiration of fully developed rice canopies of a high-yielding rice cultivar (Oryza sativa L. cv. Takanari) with a common cultivar (cv. Koshihikari) under ambient and elevated [CO2 ] (A-CO2 and E-CO2 , respectively) via leaf ecophysiological parameters derived from a free-air CO2 enrichment (FACE) experiment. Takanari had 4%-5% higher evapotranspiration than Koshihikari under both A-CO2 and E-CO2 , and E-CO2 decreased evapotranspiration of both varieties by 4%-6%. Therefore, if Takanari was cultivated under future [CO2 ] conditions, the cost for water could be maintained at the same level as for cultivating Koshihikari at current [CO2 ] with an increase in canopy photosynthesis by 36%. Sensitivity analyses determined that stomatal conductance was a significant physiological factor responsible for the greater canopy photosynthesis in Takanari over Koshihikari. Takanari had 30%-40% higher stomatal conductance than Koshihikari; however, the presence of high aerodynamic resistance in the natural field and lower canopy temperature of Takanari than Koshihikari resulted in the small difference in evapotranspiration. Despite the small difference in evapotranspiration between varieties, the model simulations showed that Takanari clearly decreased canopy and air temperatures within the planetary boundary layer compared to Koshihikari. Our results indicate that lowland rice varieties characterized by high-stomatal conductance can play a key role in enhancing productivity and moderating heat-induced damage to grain quality in the coming decades, without significantly increasing crop water use.

Fluorescence Redox Blinking Adaptable to Structural Analysis of Nucleic Acids.

The phenomenon of blinking is unique to single-molecule fluorescence measurements. By designing a fluorophore with an appropriate dark-state lifetime τoff , a kinetic analysis based on the control of fluorescence blinking (KACB) was devised to investigate the dynamics of biomolecules. By controlling the redox-reaction-based blinking (rKACB), conformational dynamics of RNA at the single-molecule level was previously investigated. However, there is little knowledge about suitable fluorescent molecules for rKACB, and the application of rKACB has been limited to the analysis of hairpins and duplex structures of nucleic acids. In this work, various fluorescent molecules, including Alexa 488, R6G, TAMRA, ATTO 647N and ATTO 655, were evaluated for rKACB. Moreover, rKACB was adapted to the discrimination of DNA/DNA and DNA/RNA nucleic acid duplexes and investigation of antigen-antibody interactions. By changing the size of the oxidant, it was possible to determine the solvent accessibility of the target domain of the analyzed biomolecules.