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In cereal plants, the size of the panicle (inflorescence) is a critical factor for yield. Panicle size is determined by a complex interplay of genetic and environmental factors, but the mechanisms underlying adaptations to temperature stress during panicle development remain largely unknown. We identify the rice THERMOSENSITIVE BARREN PANICLE (TAP) gene, which encodes a transposase-derived FAR1-RELATED SEQUENCE (FRS) protein and is responsible for regulating panicle and spikelet development at high ambient temperature. The tap mutants display high temperature-dependent reproductive abnormalities, including compromised secondary branch and spikelet initiation and pleiotropic floral organ defects. Consistent with its thermosensitive phenotype, TAP expression is induced by high temperature. TAP directly promotes the expression of OsYABBY3 (OsYAB3), OsYAB4, and OsYAB5, which encode key transcriptional regulators in panicle and spikelet development. In addition, TAP physically interacts with OsYAB4 and OsYAB5 proteins; phenotypic analysis of osyab4 tap-1 and osyab5 tap-1 double mutants indicates that TAP-OsYAB4/OsYAB5 complexes act to maintain normal panicle and spikelet development. Taken together, our study reveals the novel role of a TE-derived transcription factor in controlling rice panicle development under high ambient temperatures, shedding light on the molecular mechanism underlying the adaptation of cereal crops to increasing environmental temperatures.

Arsenic and antimony are common toxic metalloids found in associated minerals. These metalloids generally cause high-concentration pollution in non-ferrous metal smelting soils; however, few studies have investigated the pollution characteristics of these two metalloids at non-ferrous smelting sites using varying soil particle sizes. In this study, the valency distributions and geochemical fractions were investigated with varying soil particle sizes (≤ 0.05, 0.05-0.25, 0.25-1, and 1-2 mm). Soils were mainly concentrated in ≤ 0.05 and 0.05-0.25 mm with mass percentages of 32.97% and 29.02%, respectively. The highest total As and Sb concentrations in ≤ 0.05 mm were found to be 20,350 and 3655 mg/kg, respectively. In addition, As(Ⅲ), As(Ⅴ), Sb(Ⅲ), and Sb(Ⅴ) concentrations in this soil particle size were found to be 224, 19,813, 1036, and 24 mg/kg, respectively. The geochemical fractions of As and Sb in varying soil particle sizes were mainly residual, accounting for 50% and 90% in the ≤ 0.05 mm. Soil may bind ≤ 0.25 mm due to the disparity found in the geochemical compositions and valency distributions of arsenic and antimony. X-ray diffraction and scanning electron microscopy/energy dispersive system analysis confirmed that arsenolite accumulated in particle sizes of ≤ 0.05 and 0.05-0.25 mm. The results of this study may provide a scientific reference for risk assessment and restoration strategies for non-ferrous metal smelting soils.

The mammalian BREAST CANCER 2 (BRCA2) gene is a tumor suppressor that plays a crucial role in DNA repair and homologous recombination (HR). Here, we report the identification and characterization of OsBRCA2, the rice orthologue of human BRCA2. Osbrca2 mutant plants exhibit normal vegetative growth but experience complete male and female sterility as a consequence of severe meiotic defects. Pairing, synapsis and recombination are impaired in osbrca2 male meiocytes, leading to chromosome entanglements and fragmentation. In the absence of OsBRCA2, localization to the meiotic chromosome axes of the strand-invasion proteins OsRAD51 and OsDMC1 is severely reduced and in vitro OsBRCA2 directly interacts with OsRAD51 and OsDMC1. These results indicate that OsBRCA2 is essential for facilitating the loading of OsRAD51 and OsDMC1 onto resected ends of programmed double-strand breaks (DSB) during meiosis to promote single-end invasions of homologous chromosomes and accurate recombination. In addition, treatment of osbrca2-1 seedlings with mitomycin C (MMC) led to hypersensitivity. As MMC is a genotoxic agent that creates DNA lesions in the somatic cells that can only be repaired by HR, these results suggest that OsBRCA2 has a conserved role in DSB repair and HR in rice.

Fil: Zhang, Ye. China Pharmaceutical University. State Key Laboratory of Natural Medicines. Center for New Drug Safety Evaluation and Research; China Fil: Yang, Xue. China Pharmaceutical University. State Key Laboratory of Natural Medicines. Center for New Drug Safety Evaluation and Research; China Fil: Yan, Wenchao. China Pharmaceutical University. State Key Laboratory of Natural Medicines. Center for New Drug Safety Evaluation and Research; China Fil: Li, Rui. China Pharmaceutical University. State Key Laboratory of Natural Medicines. Center for New Drug Safety Evaluation and Research; China Fil: Ye, Qian. China Pharmaceutical University. State Key Laboratory of Natural Medicines. Center for New Drug Safety Evaluation and Research; China Fil: You, Linjun. China Pharmaceutical University. State Key Laboratory of Natural Medicines. Center for New Drug Safety Evaluation and Research; China Fil: Xie, Wenhao. China Pharmaceutical University. State Key Laboratory of Natural Medicines. Center for New Drug Safety Evaluation and Research; China Fil: Mo, Kun. China Pharmaceutical University. State Key Laboratory of Natural Medicines. Center for New Drug Safety Evaluation and Research; China Fil: Fu, Ruifeng. China Pharmaceutical University. State Key Laboratory of Natural Medicines. Center for New Drug Safety Evaluation and Research; China Fil: Wang, Yanxiang. China Pharmaceutical University. State Key Laboratory of Natural Medicines. Center for New Drug Safety Evaluation and Research; China Fil: Chen, Yufei. China Pharmaceutical University. State Key Laboratory of Natural Medicines. Center for New Drug Safety Evaluation and Research; China Fil: Yang, Yong. China Pharmaceutical University. State Key Laboratory of Natural Medicines. Center for New Drug Safety Evaluation and Research; China Fil: Birnbaumer, Lutz. Pontificia Universidad Católica Argentina. Facultad de Ciencias Médicas. Instituto de Investigaciones Biomédicas; Argentina Fil: Birnbaumer, Lutz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Di, Qin. Nanjing Sport Institute. School of Sports and Health; China Fil: Li, Xianjing. China Pharmaceutical University. State Key Laboratory of Natural Medicines. Center for New Drug Safety Evaluation and Research; China Abstract: Sepsis, a systemic inflammatory response syndrome (SIRS) caused by infection, is a major public health concern with limited therapeutic options. Infection disturbs the homeostasis of host, resulting in excessive inflammation and immune suppression. This has prompted the clinical use of immunomodulators to balance host response as an alternative therapeutic strategy. Here, we report that Thymopentin (TP5), a synthetic immunomodulator pentapeptide (Arg-Lys-Asp-Val-Tyr) with an excellent safety profile in the clinic, protects mice against cecal ligation and puncture (CLP)-induced sepsis, as shown by improved survival rate, decreased level of pro-inflammatory cytokines and reduced ratios of macrophages and neutrophils in spleen and peritoneum. Regarding mechanism, TP5 changed the characteristics of LPS-stimulated macrophages by increasing the production of 15-deoxy-Δ12,14 -prostaglandin J2 (15-d-PGJ2). In addition, the improved effect of TP5 on survival rates was abolished by the peroxisome proliferator-activated receptor γ (PPARγ) antagonist GW9662. Our results uncover the mechanism of the TP5 protective effects on CLP-induced sepsis and shed light on the development of TP5 as a therapeutic strategy for lethal systemic inflammatory disorders.

Plants employ dynamic molecular networks to control development in response to environmental changes, yet the underlying mechanisms are largely unknown. Here we report the identification of two rice leucine-rich repeat receptor-like kinases, Thermo-Sensitive Genic Male Sterile 10 (TMS10) and its close homolog TMS10-Like (TMS10L), which redundantly function in the maintenance of the tapetal cell layer and microspore/pollen viability under normal temperature conditions with TMS10 playing an essential role in higher temperatures (namely, 28 °C). tms10 displays male sterility under high temperatures but male fertility under low temperatures, and the tms10 tms10l double mutant shows complete male sterility under both high and low temperatures. Biochemical and genetic assays indicate that the kinase activity conferred by the intracellular domain of TMS10 is essential for tapetal degeneration and male fertility under high temperatures. Furthermore, indica or japonica rice varieties that contain mutations in TMS10, created by genetic crosses or genome editing, also exhibit thermo-sensitive genic male sterility. These findings demonstrate that TMS10 and TMS10L act as a key switch in postmeiotic tapetal development and pollen development by buffering environmental temperature changes, providing insights into the molecular mechanisms by which plants develop phenotypic plasticity via genotype-environment temperature interaction. TMS10 may be used as a genetic resource for the development of hybrid seed production systems in crops.

Previous studies have revealed the functions of rice and maize

This research aimed to comparatively evaluate the influences of root restriction (RR) cultivation and traditional cultivation (RC) on grape berry skin metabolomics using a non-targeted metabolomics method. Two-hundred-and-ninety-one metabolites were annotated and the kinetics analyses showed that berry skin metabolome is stage- and cultivation-dependent. Our results showed that RR influences significantly the metabolomes of berry skin tissues, particularly on secondary metabolism, and that this effect is more obvious at pre-veraison stage, which was evidenced by the early and fast metabolic shift from primary to secondary metabolism. Altogether, this study provided an insight into metabolic adaptation of berry skin to RR stress and expanded general understanding of berry development.

Previous studies have revealed the functions of rice and maize AGAMOUS LIKE 6 (AGL6) genes OsMADS6 and ZAG3, respectively, in floral development; however, the functions of three wheat (Triticum aestivum) AGL6 genes are still unclear. Here, we report the main functions of wheat AGL6 homoeologous genes in stamen development. In RNAi plants, stamens showed abnormality in number and morphology, and a tendency to transform into carpels. Consistently, the expression of the B-class gene TaAPETALA3 (AP3) and the auxin-responsive gene TaMGH3 was downregulated, whereas the wheat ortholog of the rice carpel identity gene DROOPING LEAF was ectopically expressed in RNAi stamens. TaAGL6 proteins bind to the promoter of TaAP3 directly. Yeast one-hybrid and transient expression assays further showed that TaAGL6 positively regulates the expression of TaAP3 in vivo. Wheat AGL6 transcription factors interact with TaAP3, TaAGAMOUS and TaMADS13. Our findings indicate that TaAGL6 transcription factors play an essential role in stamen development through transcriptional regulation of TaAP3 and other related genes. We propose a model to illustrate the function and probable mechanism of this regulation. This study extends our understanding of AGL6 genes.

La 0.8 Ca 0.2 FeO 3 perovskite (LCF) honeycombs stabilized by MgAl 2 O 4 spinel (MgAl) washcoat have been developed for the first time and applied in catalytic combustion of air diluted CH 4 (0.5 vol.%). The honeycombs were prepared by washcoating the α-Al 2 O 3 monoliths in sequence with the slurries of MgAl and LCF precursors, intermediated by calcination at corresponding temperatures. The effects of LCF powder preparation method, the calcination temperature and thickness of MgAl washcoat, and the loading of LCF were investigated. Meanwhile, the first order reaction rate constants ( k ) were calculated and activation energy ( E a ) regressed for powder and honeycomb LCF catalysts. The LCF prepared by a modified co-precipitation method was found more active and stable than that made by citrate method in literature. Calcination of bulk LCF powder at 700–800 °C led to a linear deactivation proportional to S BET . For LCF honeycombs immediately washcoated on α-Al 2 O 3 substrates, k and E a values are comparable to that measured with LCF powder, which is almost inert upon calcination at 1000 °C. When supported on MgAl washcoat, activity of LCF honeycombs is enhanced by folds, and the effect is more pronounced at higher calcination or reaction temperatures. Meanwhile, performance of the honeycombs is very sensitive to the washcoat preparation, with the optimum calcination temperature and proper thickness of the MgAl washcoat identified as 850 °C and 40 μm, respectively. Conversion of CH 4 goes up with LCF loading of honeycombs, but the values of k and E a vary in different way. When LCF loading is low, k is the highest, accompanied by a lowest E a ∼99 kJ/mol; for intermediate loadings, k and E a are both medium and constant; in cases of overloaded LCF, k reduces and E a rises to 132 kJ/mol, approaching to that measured with bulk LCF (135 kJ/mol). The change of E a with LCF loadings reflects the modification of active sites due to the interaction of LCF with MgAl, and the proper mass ratio of LCF/MgAl is at the range of 0.8–0.9. Finally, thermal resistance of LCF honeycombs supported by MgAl or MgO were compared after thermal aging at 1000 °C for 4 h. The MgAl supported LCF is about 200 °C more stable than MgO supported, indicating a much improved thermal resistance.