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Changtian Pan Dandan Yang Xiaolin Zhao Chen Jiao Yanqiu Yan Anthony Tumbeh Lamin‐Samu Qiaomei Wang Xiangyang Xu Zhangjun Fei Gang Lu 《Plant, cell & environment》2019,42(4):1205-1221
High temperature (HT) is becoming an increasingly serious factor in limiting crop production with global climate change. During hot seasons, owing to prevailing HT, cultivated tomatoes are prone to exhibiting stigma exsertion, which hampers pollination and causes fruit set failure. However, the underlying regulatory mechanisms of the HT‐induced stigma exsertion remain largely unknown. Here, we demonstrate that stigma exsertion induced by HT in cultivated tomato is caused by more seriously shortened stamens than pistils, which is different from the stigma exsertion observed in wild tomato species. Under the HT condition, the different responses of pectin, sugar, expansin, and cyclin cause cell wall remodelling and differentially localized cell division and selective cell enlargement, which further determine the lengths of stamens and pistils. In addition, auxin and jasmonate (JA) are implicated in regulating cell division and cell expansion in stamens and pistils, and exogenous JA instead of auxin treatment can effectively rescue tomato stigma exsertion through regulating the JA/COI1 signalling pathway. Our findings provide a better understanding of stigma exsertions under the HT condition in tomato and uncover a new function of JA in improving plant abiotic stress tolerance. 相似文献
125.
Hanxing Wan Xiong Ying Chen Fenglian Zhang Jun Chen Fenglan Chu Zachary M. Sellers Feng Xu Hui Dong 《The Journal of biological chemistry》2022,298(5)
Although capsaicin has been studied extensively as an activator of the transient receptor potential vanilloid cation channel subtype 1 (TRPV1) channels in sensory neurons, little is known about its TRPV1-independent actions in gastrointestinal health and disease. Here, we aimed to investigate the pharmacological actions of capsaicin as a food additive and medication on intestinal ion transporters in mouse models of ulcerative colitis (UC). The short-circuit current (Isc) of the intestine from WT, TRPV1-, and TRPV4-KO mice were measured in Ussing chambers, and Ca2+ imaging was performed on small intestinal epithelial cells. We also performed Western blots, immunohistochemistry, and immunofluorescence on intestinal epithelial cells and on intestinal tissues following UC induction with dextran sodium sulfate. We found that capsaicin did not affect basal intestinal Isc but significantly inhibited carbachol- and caffeine-induced intestinal Isc in WT mice. Capsaicin similarly inhibited the intestinal Isc in TRPV1 KO mice, but this inhibition was absent in TRPV4 KO mice. We also determined that Ca2+ influx via TRPV4 was required for cholinergic signaling–mediated intestinal anion secretion, which was inhibited by capsaicin. Moreover, the glucose-induced jejunal Iscvia Na+/glucose cotransporter was suppressed by TRPV4 activation, which could be relieved by capsaicin. Capsaicin also stimulated ouabain- and amiloride-sensitive colonic Isc. Finally, we found that dietary capsaicin ameliorated the UC phenotype, suppressed hyperaction of TRPV4 channels, and rescued the reduced ouabain- and amiloride-sensitive Isc. We therefore conclude that capsaicin inhibits intestinal Cl- secretion and promotes Na+ absorption predominantly by blocking TRPV4 channels to exert its beneficial anti-colitic action. 相似文献
126.
文章运用Agilent 双标记表达谱芯片, 基于已建立的苏太猪大肠杆菌F18菌株敏感性和抗性型全同胞配对个体, 分析十二指肠组织基因表达谱差异, 旨在筛选导致仔猪断奶后腹泻和水肿病发生的大肠杆菌F18菌株受体相关基因, 探讨造成大肠杆菌病抗性和敏感性资源家系抗性差异的分子生物学机理。研究结果显示, 以Fold change绝对值大于2倍进行筛选, 在敏感型(GG基因型)对抗性型(AA基因型)配对组中, 差异基因共13个, 其中上调6个, 下调7个, 在以敏感型(AG基因型)对抗性型(AA基因型)配对组中, 共筛选出差异基因6个, 其中上调4个, 下调2个。经GO分析发现差异基因的生物学过程主要涉及免疫应答、胞外区修饰(如糖基化)、细胞黏附、信号转导等。通路发现大肠杆菌F18菌株抵抗性和敏感性差异基因主要涉及糖脂合成代谢以及炎症免疫相关通路, 经芯片筛选出的相关基因的功能还需进一步的研究验证。 相似文献
127.
Pan Kai-Yu 《植物分类学报:英文版》1988,26(6):429-442
Ten new species, three new varieties and a new section of the family Gesneriaceae are described from China in the present paper. They are Tremacron urceolatum
K. Y. Pan from Muli of SW Sichuan, T. obliquifolium K. Y. Pan from Miyi and Yanyuan
of SW Sichuan, T. aurantiacum K. Y. Pan from Mabian and Pinshan of S Sichuan, lsometrum
Sect. Chorianthera W. T. Wang et K. Y. Pan (with I. eximium Chun as the section type),
Isometrum eximium Chun ex K. Y. Pan from Jiulong, Muli and Jinyang of SW Sichuan;
Ancylostemon mairei (Levl.) Craib var. emeiensis K. Y. Pan from Mt. Emei of Sichuan, A.
aureus (Franch.) Burtt var. angustifolius K. Y. Pan from Zhenkang of SW Yunnan, A. gamosepalus K. Y. Pan from Hanyuan, Yanyuan and Yuexi of SW Sichuan, A. rhombifolius K.
Y. Pan from Meigu of SW Sichuan, A. ronganensis K. Y. Pan from Rong an of Guangxi;
Corallodiscus flabellatus) (Craib) Burtt var. puberulus K.Y. Pan from Zhongdian and Deqin
of NW Yunnan, Nanchuan of S Sichuan and Zayü of Xizang (Tibet), Beccarinda minima
K. Y. Pan from Jinxiu and Xiangzhou of Guangxi, Boeica stolonifera K. Y. Pan from Fangcheng, Shiwandashan, Pingnan and Dongxing of S Guangxi, B. multinervia K. Y. Pan from
Yingjiang of W Yunnan, and Paraboea barbatipes K. Y. Pan from Napo of W Guangxi and
Xichou of SE Yunnan. 相似文献
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129.
Huan Chen Lemin Li Jing Ren Yang Wang Yangming Zhao Xiong Wang Sheng Wang Shizhong Xu 《PloS one》2015,10(12)
This paper aims at minimizing the communication cost for collecting flow information in Software Defined Networks (SDN). Since flow-based information collecting method requires too much communication cost, and switch-based method proposed recently cannot benefit from controlling flow routing, jointly optimize flow routing and polling switch selection is proposed to reduce the communication cost. To this end, joint optimization problem is formulated as an Integer Linear Programming (ILP) model firstly. Since the ILP model is intractable in large size network, we also design an optimal algorithm for the multi-rooted tree topology and an efficient heuristic algorithm for general topology. According to extensive simulations, it is found that our method can save up to 55.76% communication cost compared with the state-of-the-art switch-based scheme. 相似文献
130.
Guo Zhao Xiaobing Gu Xinlun Lu Jinjin Pan Zhiqiang Duan Kunkun Zhao Min Gu Qingtao Liu Liang He Jian Chen Shengqiang Ge Yanhong Wang Sujuan Chen Xiaoquan Wang Daxin Peng Hongquan Wan Xiufan Liu 《PloS one》2012,7(9)
There has been multiple evidence that domestic poultry may act as a vessel for the generation of novel influenza A viruses. In this study, we have analyzed the evolution and pathogenicity of 4 H5N2 avian influenza viruses isolated from apparently healthy poultry from H5N1 virus endemic areas in China. Phylogenetic analysis revealed that two of these viruses, A/duck/Eastern China/1111/2011 (DK/EC/1111/11) and A/goose/Eastern China/1112/2011 (GS/EC/1112/11) were derived from reassortment events in which clade 2.3.4 highly pathogenic avian influenza (HPAI) H5N1 viruses acquired novel neuraminidase and nonstructural protein genes. Another two isolates, A/chicken/Hebei/1102/2010 (CK/HB/1102/10) and A/duck/Hebei/0908/2009 (DK/HB/0908/09), possess hemagglutinin (HA) gene belong to clade 7 H5 viruses and other genes from endemic H9N2 viruses, or from viruses of various subtypes of the natural gene pool. All of these H5N2 isolates bear characteristic sequences of HPAI virus at the cleavage site of HA, and animal experiments indicated that all of these viruses but DK/HB/0908/09 is highly pathogenic to chickens. In particular, DK/EC/1111/11 and GS/EC/1112/11 are also highly pathogenic to ducks and moderately pathogenic to mice. All of these 4 viruses were able to replicate in domestic ducks and mice without prior adaptation. The emergence of these novel H5N2 viruses adds more evidence for the active evolution of H5 viruses in Asia. The maintenance of the highly pathogenic phenotype of some of these viruses even after reassortment with a new NA subtypes, their ability to replicate and transmit in domestic poultry, and the pathogenicity in the mammalian mouse model, highlight the potential threat posed by these viruses to both veterinary and public health. 相似文献