OsWRKY78 regulates panicle exsertion via gibberellin signaling pathway in rice

Panicle exsertion is one of the crucial agronomic traits in rice(Oryza sativa).Shortening of panicle exsertion often leads to panicle enclosure and severely reduces seed production.Gibberellin(GA)plays important roles in regulating panicle exsertion.However,the underlying mechanism and the relative regulatory network remain elusive.Here,we characterized the oswrky78 mutant showing severe panicle enclosure,and found that the defect of oswrky78 is caused by decreased bioactive GA contents.Biochemical analysis demonstrates that OsWRKY78 can directly activate GA biosynthesis and indirectly suppress GA metabolism.Moreover,we found OsWRKY78 can interact with and be phosphorylated by mitogen-activated protein kinase(MAPK)kinase OsMAPK6,and this phosphorylation can enhance OsWRKY78 stability and is necessary for its biological function.Taken together,these results not only reveal the critical function of OsWRKY78,but also reveal its mechanism via mediating crosstalk between MAPK and the GA signaling pathway in regulating panicle exsertion.

数据驱动的高速列车轴承多模态运行监控与故障诊断

高速列车多个轴承动态运行于相似环境造成轴承温度具有空间和时间相关性,可利用轴温相关关系的非期望变化进行轴承故障诊断;但传统的单一模态建模与监控方法未考虑在不同区间运行的列车其轴承温度具有各异的动态特征,难以建模上述关系,易造成误诊断.针对上述问题,本文研究综合利用高速列车轴温监测系统采集的同一列车多轴轴温数据,以及列车控制系统和轴承故障报警系统中的列车运行轨迹数据,提出数据驱动的列车轴承多模态运行监控与故障诊断方法.首先,针对列车通讯异常和传感器故障造成的缺失点和离群点问题,提出线性插值和动态主元搜索相结合的列车轴温数据预处理方法;接下来,依据不同运行区间内轴承温度变化相似性的聚类结果识别出同一列车的不同运行模态,并结合其与故障报警地理信息所提取的运行区间之间的相关性,提出基于列车运行轨迹的运行模态识别方法;在此基础上,提出多模态动态内在典型相关分析(multi-modal dynamic inner canonical correlation analysis, M-DiCCA)列车轴承多模态建模与运行监控方法;其后,提出基于动态时间规整的轴承故障原因诊断方法;最后,采用实际列车运行的轴温数据进行实验验证,结果表明了所提方法的有效性.

bZIP71 delays flowering by suppressing Ehd1 expression in rice

Flowering time is a fundamental factor determining the global distribution and final yield of rice(Oryza sativa).Although diverse flowering time genes have been reported in this crop,the transcriptional regulation of its key flowering genes are poorly understood.Here,we report that a basic leucine zipper transcription factor,bZIP71,functions as a flowering repressor.The overexpression of bZIP71 delays flowering,while the bzip71 mutant flowers early in both long-day and short-day conditions.A genetic analysis showed that the regulation of flowering by bZIP71 might be independent of Heading date 2(Hd2),Hd4,and Hd5.Importantly,bZIP71 directly associates with the Early heading date 1(Ehd1)promoter and represses its transcription,and genetically the function of bZIP71 is impaired in the ehd1 mutant.Moreover,bZIP71 interacts with major components of polycomb repressive complex 2(PRC2),SET domain group protein 711(SDG711),and Fertilization independent endosperm 2(FIE2),through which bZIP71 regulates the H3K27me3 level of Ehd1.Taken together,we present a transcriptional regulatory mechanism in which bZIP71 enhances the H3K27me3 level of Ehd1 and transcriptionally represses its expression,which not only offers a novel insight into a flowering pathway,but also provides a valuable putative target for the genetic engineering and breeding of elite rice cultivars.

QNE1 is a key flowering regulator determining the length of the vegetative period in soybean cultivars

The soybean E1 gene is a major regulator that plays an important role in flowering time and maturity.However,it remains unclear how cultivars carrying the dominant E1 allele adapt to the higher latitudinal areas of northern China.We mapped the novel quantitative trait locus QNE1(QTL near E1) for flowering time to the region proximal to E1 on chromosome 6 in two mapping populations.Positional cloning revealed Glyma.06G204300,encoding a TCP-type transcription factor,as a strong candidate gene for QNE1.Association analysis further confirmed that functional single nucleotide polymorphisms(SNPs) at nucleotides 686 and 1,063 in the coding region of Glyma.06G204300 were significantly associated with flowering time.The protein encoded by the candidate gene is localized primarily to the nucleus.Furthermore,soybean and Brassica napus plants overexpressing Glyma.06G204300 exhibited early flowering.We conclude that despite their similar effects on flowering time,QNE1 and E4 may control flowering time through different regulatory mechanisms,based on expression studies and weighted gene co-expression network analysis of flowering time-related genes.Deciphering the molecular basis of QNE1 control of flowering time enriches our knowledge of flowering gene networks in soybean and will facilitate breeding soybean cultivars with broader latitudinal adaptation.

Design,synthesis and biological evaluation of pyridyl substituted benzoxazepinones as potent and selective inhibitors of aldosterone synthase

Exorbitant aldosterone is closely associated with various severe diseases,including congestive heart failure and chronic kidney disease.As aldosterone synthase is the pivotal enzyme in aldosterone biosynthesis,its inhibition constitutes a promising treatment for these diseases.Via a structure-based approach,a series of pyridyl substituted 3,4-dihydrobenzo[f][1,4]oxazepin-5(2 H)-ones were designed as inhibitors of aldosterone synthase.Six compounds(5 j,5 l,5 m 5 w,5 x and 5 y)distinguished themselves with potent inhibition(IC50<100 nmol/L)and high selectivity over homogenous 11β-hydroxylase.As the most promising compound,5 x exhibited an IC_(50) of 12 nmol/L and an excellent selectivity factor(SF)of157,which are both superior to those of the re ference fadrazole(IC_(50)=21 nmol/L,SF=7).Importantly,5 x showed no inhibition against steroidogenic CYP17,CYP19 and a panel of hepatic CYP enzymes indicating an outstanding sa fety profile.As it manifested satis factory pharmacokinetic pro perties in rats,compound5 x was considered as a drug candidate for further development.

Piezoelectric inertial robot for operating in small pipelines based on stick-slip mechanism:modeling and experiment

Small pipes exist in industrial and biomedical fields,and require microrobots with high operational precision and large load capacity to inspect or perform functional tasks.A piezoelectric inertial pipeline robot using a“stick-slip”mechanism was proposed to address this requirement.In this study,the driving principle of the proposed robot was analyzed,and the strategy of the design scheme was presented.A dynamics model of the stick-slip system was established by combining the dynamics model of the driving foot system and the LuGre friction model,and the simulation analysis of the effect of system parameters on the operating trajectory was performed.An experimental system was established to examine the output characteristics of the proposed robot.Experimental results show that the proposed pipeline robot with inertial stick-slip mechanism has a great load capacity of carrying 4.6 times(70 g)its own mass and high positioning accuracy.The speed of the pipeline robot can reach up to 3.5 mm/s(3 mm/s)in the forward(backward)direction,with a minimum step distance of 4µm.Its potential application for fine operation in the pipe is exhibited by a demonstration of contactless transport.

Design of a linear-rotary ultrasonic motor for optical focusing inspired by the bionic motion principles of the earthworms

Multi-motor configuration of multi-DOF(degree of freedom)optical system is a major source of redundant structure,putting a limitation on the simple and miniaturized design.Thus,a novel two-DOF ultrasonic motor(USM)is proposed to provide a feasible method of application in the lens autofocus of the optical system.The proposed USM operates by one longitudinal mode and two orthogonal bending modes,which is inspired by the bionic motion principle of the earthworms.The frequency degeneration among the three working modes is per-formed,and the working principle of the USM is verified via the FEM simulation.A prototype of the two-DOF USM is fabricated,and its mechanical output characteristics are tested.The experimental results indicate that the prototype achieves the maximum rotary and linear speeds of 3319.6 rpm and 57.6 mm/s,respectively.Furthermore,we demonstrate the result of a simple focusing experiment using the prototype and obtain a series of clear pictures,which verifies the feasibility of application in the optical focusing system.