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Biology subjects

Yoshimoto, M.

Publications and source records attributed to Yoshimoto, M..

3 recordsLinked to original sources

An early-morning flowering trait in rice helps retain grain yield under heat stress field conditions at flowering stage

Early-morning flowering (EMF) trait is supposed to be effective in retaining grain yield due to mitigation of heat-induced spikelet sterility at flowering in rice. This study evaluated (i) phenotypic differences between a near-isogenic line carrying a QTL for EMF trait, designated as IR64+qEMF3, and a recurrent parent, IR64, under wide variation in climates and (ii) whether an EMF trait can retain grain yield under heat stress at flowering. IR64+qEMF3 had significant earlier flower opening time (FOT) in diverse environmental conditions including temperate, subtropical, and tropical regions. Under normal temperatures at flowering, IR64+qEMF3 had similar grain yield to IR64 with some significant changes in agronomic traits and yield components. Field trials in heat-vulnerable regions of central Myanmar for seven crop seasons showed that higher percentage of filled grains contributed to the significantly higher grain yield in IR64+qEMF3 among yield components when plants were exposed to daily maximum air temperatures around 36.5 {degrees}C or higher. Lower spikelet sterility in IR64+qEMF3 was attributed to the earlier FOT during cooler early morning hours. This is the first field study that clearly demonstrates the advantage of the EMF trait for retaining grain yield by stabilizing percentage of fertile grains under heat stress at flowering.

developmental biology

B-1 lymphoid cells develop independently of Notch signaling during mouse embryonic development.

The in vitro generation from pluripotent stem cells (PSCs) of different blood cell types, in particular those that are not replenished by hematopoietic stem cells (HSCs) like fetal-derived tissue-resident macrophages and innate-like lymphocytes, is of a particular interest. In order to succeed in this endeavor, a thorough understanding of the pathway interplay promoting lineage specification for the different blood cell types is needed. Notch signaling is essential for the HSC generation and their derivatives, but its requirement for tissue-resident immune cells is unknown. Using mouse embryonic stem cells (mESCs) to recapitulate murine embryonic development, we have studied the requirement for Notch signaling during the earliest B-lymphopoiesis and found that Rbpj-deficient mESCs are able to generate B-1 cells. Their Notch-independence was confirmed in ex vivo experiments using Rbpj-deficient embryos. In addition, we found that upregulation of Notch signaling was needed for the emergence of B-2 lymphoid cells. Taken together, these findings indicate that control of Notch signaling dosage is critical for the different B-cell lineage specification and provides pivotal information for their in vitro generation from PSCs for therapeutic applications.

developmental biology

Canopy micrometeorology monitoring in diverse climates innovatively improves the evaluation heat-induced sterility of rice under climate change

This study is the first and unique of open-field studies to assess the determination process of heat-induced spikelet sterility (HISS) of rice by using the same variety and the same monitoring system, MINCER (Micrometeorological Instrument for Near Canopy Environment of Rice), covering the major-rice growing regions from Sub-Saharan Africa, South, Southeast, and East Asia, and USA. Applying the observation data from the monitoring network, MINCERnet, to the canopy heat balance model, IM2PACT, it was quantitatively corroborated in open-field conditions worldwide that the canopy and panicle transpiration and their evaporative cooling effect played a great role on the micrometeorological gap between the ambient air temperature and the panicle temperature, and that the sterility rate due to HISS in open-fields can be evaluated accurately in diverse climates by the mean panicle temperature at flowering hours in the flowering period. The heat balance structure suggested that the risk of HISS should be higher in high humidity climates rather than in dry climates also in the future, which lead to the importance of the humidity accuracy as well as of the air temperature in climate scenarios and their spatial downscaling for future prediction of rice heat stress and production. Applying the heat-tolerant variety was suggested to be able to keep the sterility due to HISS low in all climates. It is needed of the approach using the panicle temperature as indicator of HISS by intervening sub-model and/or monitoring of micrometeorology inside the canopy to reduce uncertainties in future rice yield prediction under various adaptation measures.

plant biology