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381.
Yebin Zhou Dennis F. Kucik Alexander J. Szalai Jeffrey C. Edberg 《Journal of visualized experiments : JoVE》2014,(89)
Neutrophil firm adhesion to endothelial cells plays a critical role in inflammation in both health and disease. The process of neutrophil firm adhesion involves many different adhesion molecules including members of the β2 integrin family and their counter-receptors of the ICAM family. Recently, naturally occurring genetic variants in both β2 integrins and ICAMs are reported to be associated with autoimmune disease. Thus, the quantitative adhesive capacity of neutrophils from individuals with varying allelic forms of these adhesion molecules is important to study in relation to mechanisms underlying development of autoimmunity. Adhesion studies in flow chamber systems can create an environment with fluid shear stress similar to that observed in the blood vessel environment in vivo. Here, we present a method using a flow chamber assay system to study the quantitative adhesive properties of human peripheral blood neutrophils to human umbilical vein endothelial cell (HUVEC) and to purified ligand substrates. With this method, the neutrophil adhesive capacities from donors with different allelic variants in adhesion receptors can be assessed and compared. This method can also be modified to assess adhesion of other primary cell types or cell lines. 相似文献
382.
383.
Zehua Zhou Yabing Duan Jie Zhang Fei Lu Yuanye Zhu Won Bo Shim Mingguo Zhou 《Molecular Plant Pathology》2021,22(2):163-174
In Fusarium graminearum, a trichothecene biosynthetic complex known as the toxisome forms ovoid and spherical structures in the remodelled endoplasmic reticulum (ER) under mycotoxin-inducing conditions. Previous studies also demonstrated that disruption of actin and tubulin results in a significant decrease in deoxynivalenol (DON) biosynthesis in F. graminearum. However, the functional association between the toxisome and microtubule components has not been clearly defined. In this study we tested the hypothesis that the microtubule network provides key support for toxisome assembly and thus facilitates DON biosynthesis. Through fluorescent live cell imaging, knockout mutant generation, and protein–protein interaction assays, we determined that two of the four F. graminearum tubulins, α1 and β2 tubulins, are indispensable for DON production. We also showed that these two tubulins are directly associated. When the α1–β2 tubulin heterodimer is disrupted, the metabolic activity of the toxisome is significantly suppressed, which leads to significant DON biosynthesis impairment. Similar phenotypic outcomes were shown when F. graminearum wild type was treated with carbendazim, a fungicide that binds to microtubules and disrupts spindle formation. Based on our results, we propose a model where α1–β2 tubulin heterodimer serves as the scaffold for functional toxisome assembly in F. graminearum. 相似文献
384.
Taxonomy and phylogeny of Ceriporia (Polyporales,Basidiomycota) with an emphasis of Chinese collections 总被引:1,自引:0,他引:1
Bi-Si Jia Li-Wei Zhou Bao-Kai Cui Bernard Rivoire Yu-Cheng Dai 《Mycological Progress》2014,13(1):81-93
Ceriporia accommodates a kind of wood-inhabiting polypores producing resupinate basidiocarps and causing a white rot. More than 30 species of this genus have been described; however, only a few species were referred to molecular phylogeny. In this study, a total of 203 specimens of Ceriporia were studied morphologically, and the ITS and/or nLSU regions from 42 samples, representing 18 species, were sequenced for phylogenetic analysis. Based on both morphological and phylogenetic analyses, three new species of Ceriporia, C. bubalinomarginata, C. pseudocystidiata and C. variegata, are described and illustrated. An annotated identification key is provided for all 20 species of this genus thus far known in China. Our phylogeny shows that (1) Ceriporia is not monophyletic, (2) C. spissa and C. viridans as morphologically circumscribed are polyphyletic, (3) C. inflata is retained for both C. inflata and C. jiangxiensis, and (4) presence or absence of hymenial cystidia is not a useful character in delimiting species relationships in Ceriporia. 相似文献
385.
Xiangjun Kong Aziz Khan Zhiling Li Jingyi You Fazal Munsif Haodong Kang Ruiyang Zhou 《Saudi Journal of Biological Sciences》2020,27(12):3691-3699
Chalcone synthase (CHS) is a key enzyme and producing flavonoid derivatives as well play a vital roles in sustaining plant growth and development. However, the systematic and comprehensive analysis of CHS genes in island cotton (G. barbadense) has not been reported yet especially response to cytoplasmic male sterility (CMS). To fill this knowledge gap, a genome-wide investigation of CHS genes were studied in island cotton. A total of 20 GbCHS genes were identified and grouped into five GbCHSs. The gene structure analysis revealed that most of GbCHS genes consisted of two exons and one intron, and 20 motifs were identified. Twenty five pairs duplicated events (12 GbCHS genes) were identified including 23 segmental duplication pairs and two tandem duplication events, representing that GbCHS gene family amplification mainly owned to segmental duplication events and evolving slowly. Gene expression analysis exhibited that the GbCHS family genes presented a diversity expression patterns in various organs of cotton. Coupled with functional predictions and gene expression, the abnormal expression of GbCHS06, 10, 16 and 19 might be associated with pollen abortion of CMS line in island cotton. Conclusively, GbCHS genes exhibited diversity and conservation in many aspects, which will help to better understand functional studies and a reference for CHS research in island cotton and other plants. 相似文献
386.
387.
Lüwen Zhou Fei Du Shiliang Feng Jinrong Hu Shouqin Lü Mian Long Yuling Jiao 《植物学报(英文版)》2020,62(12):1853-1867
The shape of comparable tissues and organs is consistent among individuals of a given species, but how this consistency or robustness is achieved remains an open question. The interaction between morphogenetic factors determines organ formation and subsequent shaping, which is ultimately a mechanical process. Using a computational approach, we show that the epidermal layer is essential for the robustness of organ geometry control. Specifically, proper epidermal restriction allows organ asymmetry maintenance, and the tensile epidermal layer is sufficient to suppress local variability in growth, leading to shape robustness. The model explains the enhanced organ shape variations in epidermal mutant plants. In addition, differences in the patterns of epidermal restriction may underlie the initial establishment of organ asymmetry. Our results show that epidermal restriction can answer the longstanding question of how cellular growth noise is averaged to produce precise organ shapes, and the findings also shed light on organ asymmetry establishment. 相似文献
388.
Junhui Zhou Dongdong Li Guoming Wang Fuxi Wang Merixia Kunjal Dirk Joldersma Zhongchi Liu 《植物学报(英文版)》2020,62(3):269-286
Fruit crops, including apple, orange, grape,banana, strawberry, watermelon, kiwifruit and tomato, not only provide essential nutrients for human life but also contribute to the major agricultural output and economic growth of many countries and regions in the world. Recent advancements in genome editing provides an unprecedented opportunity for the genetic improvement of these agronomically important fruit crops. Here, we summarize recent reports of applying CRISPR/Cas9 to fruit crops,including efforts to reduce disease susceptibility, change plant architecture or flower morphology, improve fruit quality traits, and increase fruit yield. We discuss challenges facing fruit crops as well as new improvements and platforms that could be used to facilitate genome editing in fruit crops, including d Cas9-base-editing to introduce desirable alleles and heat treatment to increase editing efficiency. In addition, we highlight what we see as potentially revolutionary development ranging from transgene-free genome editing to de novo domestication of wild relatives. Without doubt, we now see only the beginning of what will eventually be possible with the use of the CRISPR/Cas9 toolkit. Efforts to communicate with the public and an emphasis on the manipulation of consumerfriendly traits will be critical to facilitate public acceptance of genetically engineered fruits with this new technology. 相似文献
389.
miR164c and miR168a regulate seed vigor in rice 总被引:1,自引:0,他引:1
Yan Zhou Shiqi Zhou Liping Wang Duo Wu Hailan Cheng Xu Du Dandan Mao Chunlai Zhang Xiaocheng Jiang 《植物学报(英文版)》2020,62(4):470-486
390.