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Chlorophyll (Chl) degradation occurs during leaf senescence, embryo degreening, bud breaking, and fruit ripening. The Chl catabolic pathway has been intensively studied and nearly all the enzymes involved are identified and characterized; however, the molecular regulatory mechanisms of this pathway are largely unknown. In this study, we performed yeast one-hybrid screening using a transcription factor cDNA library to search for factors controlling the expression of Chl catabolic genes. We identified ANAC046 as a common regulator that directly binds to the promoter regions of NON-YELLOW COLORING1 , STAY-GREEN1 ( SGR1 ), SGR2 , and PHEOPHORBIDE a OXYGENASE . Transgenic plants overexpressing ANAC046 exhibited an early-senescence phenotype and a lower Chl content in comparison with the wild-type plants, whereas loss-of-function mutants exhibited a delayed-senescence phenotype and a higher Chl content. Microarray analysis of ANAC046 transgenic plants showed that not only Chl catabolic genes but also senescence-associated genes were positively regulated by ANAC046. We conclude that ANAC046 is a positive regulator of Arabidopsis leaf senescence and exerts its effect by controlling the expression of Chl catabolic genes and senescence-associated genes.

Inhibition of sodium glucose cotransporter 2 (SGLT2) has been reported as a new therapeutic strategy for treating diabetes. However, the effect of SGLT2 inhibitors on the kidney is unknown. In addition, whether SGLT2 inhibitors have an anti-inflammatory or antioxidative stress effect is still unclear. In this study, to resolve these issues, we evaluated the effects of the SGLT2 inhibitor, dapagliflozin, using a mouse model of type 2 diabetes and cultured proximal tubular epithelial (mProx24) cells. Male db/db mice were administered 0.1 or 1.0 mg/kg of dapagliflozin for 12 weeks. Body weight, blood pressure, blood glucose, hemoglobin A1c, albuminuria and creatinine clearance were measured. Mesangial matrix accumulation and interstitial fibrosis in the kidney and pancreatic β-cell mass were evaluated by histological analysis. Furthermore, gene expression of inflammatory mediators, such as osteopontin, monocyte chemoattractant protein-1 and transforming growth factor-β, was evaluated by quantitative reverse transcriptase-PCR. In addition, oxidative stress was evaluated by dihydroethidium and NADPH oxidase 4 staining. Administration of 0.1 or 1.0 mg/kg of dapagliflozin ameliorated hyperglycemia, β-cell damage and albuminuria in db/db mice. Serum creatinine, creatinine clearance and blood pressure were not affected by administration of dapagliflozin, but glomerular mesangial expansion and interstitial fibrosis were suppressed in a dose-dependent manner. Dapagliflozin treatment markedly decreased macrophage infiltration and the gene expression of inflammation and oxidative stress in the kidney of db/db mice. Moreover, dapagliflozin suppressed the high-glucose-induced gene expression of inflammatory cytokines and oxidative stress in cultured mProx24 cells. These data suggest that dapagliflozin ameliorates diabetic nephropathy by improving hyperglycemia along with inhibiting inflammation and oxidative stress.

Achieving high mobility in SnO 2 , which is a typical wide gap oxide semiconductor, has been pursued extensively for device applications such as field effect transistors, gas sensors, and transparent electrodes. In this study, we investigated the transport properties of lightly Ta-doped SnO 2 (Sn 1− x Ta x O 2 , TTO) thin films epitaxially grown on TiO 2 (001) substrates by pulsed laser deposition. The carrier density ( n e ) of the TTO films was systematically controlled by x . Optimized TTO ( x  = 3 × 10 −3 ) films with n e ~ 1 × 10 20  cm −3 exhibited a very high Hall mobility ( μ H ) of 130 cm 2 V −1 s −1 at room temperature, which is the highest among SnO 2 films thus far reported. The μ H value coincided well with the intrinsic limit of μ H calculated on the assumption that only phonon and ionized impurities contribute to the carrier scattering. The suppressed grain-boundary scattering might be explained by the reduced density of the {101} crystallographic shear planes.

A magnetically responsive photonic crystal of colloidal nanosheets can exhibit a controllable structural color, offering diverse potential applications. In this study, we systematically investigated how the lateral sizes of graphene oxide (GO) nanosheets affect their magnetic responsiveness in a photonic system. Contrary to the prediction that larger lateral sizes of nanosheets would be more responsive to an applied magnetic field based on the magnetic energy of anisotropic materials, we discovered that GO nanosheets with larger lateral sizes in the photonic system scarcely responded to a 12 T magnetic field. The lack of magnetic response may be due to the strongly restricted rotational motion of GO nanosheets by mutual electrostatic forces. In contrast, GO nanosheets with medium lateral sizes readily responded to the 12 T magnetic field, forming a uniaxially oriented structure that resulted in a vivid structural color. However, smaller GO nanosheets displayed a less vivid structural color, possibly because of less structural ordering of GO nanosheets. Finally, we found that the photonic crystal of GO nanosheets with optimized lateral sizes responded effectively to the 12 T magnetic field across various GO concentrations, resulting in a vivid and tunable structural color. We investigated the effect of nanosheet size on the magnetically responsive behavior of a photonic crystal of graphene oxide nanosheets. Contrary to the prediction based on their magnetic energy, we found that larger nanosheets exhibited poor magnetic response due to strong electrostatic repulsion, while smaller ones readily responded to a strong magnetic field, leading to a vivid structural color.

Conferring drought resistant traits to crops is one of the major aims of current breeding programs in response to global climate changes. We previously showed that exogenous application of acetic acid to roots of various plants could induce increased survivability under subsequent drought stress conditions, but details of the metabolism of exogenously applied acetic acid, and the nature of signals induced by its application, have not been unveiled. In this study, we show that rice rapidly induces jasmonate signaling upon application of acetic acid, resulting in physiological changes similar to those seen under drought. The major metabolite of the exogenously applied acetic acid in xylem sap was determined as glutamine—a common and abundant component of xylem sap—indicating that acetic acid is not the direct agent inducing the observed physiological responses in shoots. Expression of drought-responsive genes in shoot under subsequent drought conditions was attenuated by acetic acid treatment. These data suggest that acetic acid activates root-to-shoot jasmonate signals that partially overlap with those induced by drought, thereby conferring an acclimated state on shoots prior to subsequent drought.

Grain weight is an important crop yield component; however, its underlying regulatory mechanisms are largely unknown. Here, we identify a grain-weight quantitative trait locus (QTL) encoding a new-type GNAT-like protein that harbors intrinsic histone acetyltransferase activity (OsglHAT1). Our genetic and molecular evidences pinpointed the QTL- OsglHAT1 ’s allelic variations to a 1.2-kb region upstream of the gene body, which is consistent with its function as a positive regulator of the traits. Elevated OsglHAT1 expression enhances grain weight and yield by enlarging spikelet hulls via increasing cell number and accelerating grain filling, and increases global acetylation levels of histone H4. OsglHAT1 localizes to the nucleus, where it likely functions through the regulation of transcription. Despite its positive agronomical effects on grain weight, yield, and plant biomass, the rare allele elevating OsglHAT1 expression has so far escaped human selection. Our findings reveal the first example, to our knowledge, of a QTL for a yield component trait being due to a chromatin modifier that has the potential to improve crop high-yield breeding. Significance Grain weight is an important crop yield component; however, its underlying regulatory mechanisms are largely unknown. Here, we identify a grain-weight quantitative trait locus (QTL) in rice encoding a new-type GNAT-like protein that harbors intrinsic histone acetyltransferase activity (OsglHAT1). Elevated OsglHAT1 expression enhances grain weight and yield by enlarging spikelet hulls via increasing cell number and accelerating grain filling, and increases global acetylation levels of histone H4. Our findings reveal the first example, to our knowledge, of a QTL for a yield component trait being due to a chromatin modifier that has the potential to improve crop high-yield breeding.

The safety of induced pluripotent stem cells seems to depend on how they were generated. Miura et al . examine the effects of the c-myc transgene, tissue of origin and selection method on the tumor-forming propensity of iPS-cell derivatives. We evaluated the teratoma-forming propensity of secondary neurospheres (SNS) generated from 36 mouse induced pluripotent stem (iPS) cell lines derived in 11 different ways. Teratoma-formation of SNS from embryonic fibroblast–derived iPS cells was similar to that of SNS from embryonic stem (ES) cells. In contrast, SNS from iPS cells derived from different adult tissues varied substantially in their teratoma-forming propensity, which correlated with the persistence of undifferentiated cells.

Aims/Introduction We evaluated the efficacy of multifactorial intensive treatment (IT) on renal outcomes in patients with type 2 diabetes and advanced‐stage diabetic kidney disease (DKD). Materials and Methods The Diabetic Nephropathy Remission and Regression Team Trial in Japan (DNETT‐Japan) is a multicenter, open‐label, randomized controlled trial with a 5‐year follow‐up period. We randomly assigned 164 patients with advanced‐stage diabetic kidney disease (urinary albumin‐to‐creatinine ratio ≥300 mg/g creatinine, serum creatinine level 1.2–2.5 mg/dL in men and 1.0–2.5 mg/dL in women) to receive either IT or conventional treatment. The primary composite outcome was end‐stage kidney failure, doubling of serum creatinine or death from any cause, which was assessed in the intention‐to‐treat population. Results The IT tended to reduce the risk of primary end‐points as compared with conventional treatment, but the difference between treatment groups did not reach the statistically significant level (hazard ratio 0.69, 95% confidence interval 0.43–1.11; P = 0.13). Meanwhile, the decrease in serum low‐density lipoprotein cholesterol level and the use of statin were significantly associated with the decrease in primary outcome (hazard ratio 1.14; 95% confidence interval 1.05–1.23, P < 0.001 and hazard ratio 0.53, 95% confidence interval 0.28–0.998, P < 0.05, respectively). The incidence of adverse events was not different between treatment groups. Conclusions The risk of kidney events tended to decrease by IT, although it was not statistically significant. Lipid control using statin was associated with a lower risk of adverse kidney events. Further follow‐up study might show the effect of IT in patients with advanced diabetic kidney disease. The Diabetic Nephropathy Remission and Regression Team Trial in Japan was designed to clarify the beneficial effects of multifactorial intensified intervention by the team approach with medical staffs at each institution. There was an overall trend toward a lower risk on the development of kidney events in the intensive treatment group than in the conventional treatment group in this trial, but the benefit of intensive treatment could not be confirmed statistically. Lipid control by statin was associated with lower risk of kidney events in addition to strict control of blood glucose and blood pressure.

Water deficit caused by global climate changes seriously endangers the survival of organisms and crop productivity, and increases environmental deterioration 1 , 2 . Plants' resistance to drought involves global reprogramming of transcription, cellular metabolism, hormone signalling and chromatin modification 3 – 8 . However, how these regulatory responses are coordinated via the various pathways, and the underlying mechanisms, are largely unknown. Herein, we report an essential drought-responsive network in which plants trigger a dynamic metabolic flux conversion from glycolysis into acetate synthesis to stimulate the jasmonate (JA) signalling pathway to confer drought tolerance. In Arabidopsis , the ON/OFF switching of this whole network is directly dependent on histone deacetylase HDA6. In addition, exogenous acetic acid promotes de novo JA synthesis and enrichment of histone H4 acetylation, which influences the priming of the JA signalling pathway for plant drought tolerance. This novel acetate function is evolutionarily conserved as a survival strategy against environmental changes in plants. Furthermore, the external application of acetic acid successfully enhanced the drought tolerance in Arabidopsis , rapeseed, maize, rice and wheat plants. Our findings highlight a radically new survival strategy that exploits an epigenetic switch of metabolic flux conversion and hormone signalling by which plants adapt to drought. In response to drought, acetate accumulates endogenously through redirection of metabolic fluxes, and stimulates jasmonate pathways controlling Arabidopsis drought tolerance. Application of exogenous acetic acid alone increases drought tolerance of major crops such as maize, wheat and rice.

Photoreactions of acetonitrile solutions of 3,3-diaryl-1,1-dicyano-2-methylprop-1-enes (1a–c) with allyltrimethylsilane (2) in the presence of phenanthrene as a photoredox catalyst and acetic acid as a proton source formed photoallylation (3) and photoreduction (4) products via photoinduced electron transfer pathways. When (S)-mandelic acid was used as the proton source, the reactions proceeded with 3.4 and 4.8 %ee for formation of 3 and 4, respectively. The results of studies of the effect of aryl ring substituents and several chiral carboxylic acids suggested that the enantioselectivities of the reactions are governed by steric controlled proton transfer in intermediate complexes formed by π-π and OH-π interactions of anion radicals derived from 1a–c and chiral carboxylic acids.