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排序方式: 共有4177条查询结果,搜索用时 31 毫秒
71.
72.
Dan Wang Li Tian Dan-Dan Zhang Jian Song Shuang-Shuang Song Chun-Mei Yin Lei Zhou Yan Liu Bao-Li Wang Zhi-Qiang Kong Steven J. Klosterman Jun-Jiao Li Jie Wang Ting-Gang Li Sabiu Adamu Krishna V. Subbarao Jie-Yin Chen Xiao-Feng Dai 《Molecular Plant Pathology》2020,21(5):667-685
Secreted small cysteine-rich proteins (SCPs) play a critical role in modulating host immunity in plant–pathogen interactions. Bioinformatic analyses showed that the fungal pathogen Verticillium dahliae encodes more than 100 VdSCPs, but their roles in host–pathogen interactions have not been fully characterized. Transient expression of 123 VdSCP-encoding genes in Nicotiana benthamiana identified three candidate genes involved in host–pathogen interactions. The expression of these three proteins, VdSCP27, VdSCP113, and VdSCP126, in N. benthamiana resulted in cell death accompanied by a reactive oxygen species burst, callose deposition, and induction of defence genes. The three VdSCPs mainly localized to the periphery of the cell. BAK1 and SOBIR1 (associated with receptor-like protein) were required for the immunity triggered by these three VdSCPs in N. benthamiana. Site-directed mutagenesis showed that cysteine residues that form disulphide bonds are essential for the functioning of VdSCP126, but not VdSCP27 and VdSCP113. VdSCP27, VdSCP113, and VdSCP126 individually are not essential for V. dahliae infection of N. benthamiana and Gossypium hirsutum, although there was a significant reduction of virulence on N. benthamiana and G. hirsutum when inoculated with the VdSCP27/VdSCP126 double deletion strain. These results illustrate that the SCPs play a critical role in the V. dahliae–plant interaction via an intrinsic virulence function and suppress immunity following infection. 相似文献
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74.
Rui Kong 《Cell biology international》2020,44(9):1945-1956
Non‐small‐cell lung carcinoma (NSCLC) continues to top the list of cancer mortalities worldwide. The role of circular RNAs (circRNAs) in tumorigenesis has been increasingly appreciated, although it is relatively unexplored in NSCLC. Herein, we reported the role of hsa_circ_0085131 in NSCLC. In the present study, NSCLC tumor specimens exhibited a higher hsa_circ_0085131 level in comparison to para‐tumor samples. And the higher level of hsa_circ_0085131 was associated with recurrence and poorer survival of NSCLC. Moreover, hsa_circ_0085131 promoted cell proliferation and cisplatin (DDP)‐resistance. Furthermore, hsa_circ_0085131 regulated cell DDP‐resistance by modulating autophagy. Hsa_circ_0085131 acted as a competing endogenous RNA of miR‐654‐5p to release autophagy‐associated factor ATG7 expression, thereby promoting cell chemoresistance. In conclusion, hsa_circ_0085131 enhances DDP‐resistance of NSCLC cells through sequestering miR‐654‐5p to upregulate ATG7, leading to cell autophagy. Therefore, these findings advocate targeting the hsa_circ_0085131/miR‐654‐5p/ATG7 axis as a potential therapeutic option for patients with NSCLC who are resistant to DDP. 相似文献
75.
Yuwen Wang Songyun Zou Zhuyun Zhao Po Liu Changneng Ke Shi Xu 《Cell biology international》2020,44(8):1564-1576
Small‐cell lung cancer (SCLC) accounts for approximately 15% of lung cancer cases; however, it is characterized by easy relapse and low survival rate, leading to one of the most intractable diseases in clinical practice. Despite decades of basic and clinical research, little progress has been made in the management of SCLC. The current standard first‐line regimens of SCLC still remain to be cisplatin or carboplatin combined with etoposide, and the adverse events of chemotherapy are by no means negligible. Besides, the immunotherapy on SCLC is still in an early stage and novel studies are urgently needed. In this review, we describe SCLC development and current therapy, aiming at providing useful advices on basic research and clinical strategy. 相似文献
76.
Jing Zhang Xin Xu Xingfa Huang Huiling Zhu Hongbo Chen Wenjun Wang Yulan Liu 《Innate immunity》2020,26(5):435
In the present study, we used microRNA (miRNA) sequencing to discover and explore the expression profiles of known and novel miRNAs in 1000 ng/ml LPS stimulated for 8 h vis-à-vis non-stimulated (i.e. control) PBMCs isolated from the blood of healthy pigs. A total of 291 known miRNAs were bio-computationally identified in porcine PBMCs, and 228 novel miRNAs (not enlisted in the swine mirBase) were identified. Among these miRNAs, ssc-miR-148a-3p, ssc-let-7g, ssc-let-7f, 3_8760, ssc-miR-26a, ssc-miR-451, ssc-miR-21, ssc-miR-30d, ssc-miR-99a and ssc-miR-103 were the top 10 most abundant miRNAs in porcine PBMCs. Through miRNA differential analysis combined with quantitative PCR, we found the expressions of ssc-miR-122, ssc-miR-129b, ssc-miR-17-5p and ssc-miR-152 were significantly changed in porcine PBMCs after LPS stimulation. Furthermore, targets prediction and function analysis indicated a significant enrichment in gene ontology functional categories related to diseases, immunity and inflammation. In conclusion, this study on profiling of miRNAs expressed in LPS-stimulated PBMCs provides an important reference point for future studies on regulatory roles of miRNAs in porcine immune system. 相似文献
77.
四川黑竹沟国家级自然保护区位于生物多样性丰富的凉山山系, 在保护和维持区域生物多样性方面具有极其重要的地位, 然而对该自然保护区兽类群落的研究却极为缺乏。为了了解该自然保护区及周边的小型兽类群落,本文作者在2018年4-10月调查了该区域的非飞行小型兽类物种多样性及其群落组成。在海拔1,537-3,830 m间共设置样方184个, 布设鼠夹9,016铗日, 捕获小型兽类536只, 隶属4目7科13属21种。包括滇攀鼠(Vernaya fulva)和等齿鼩鼹(Uropsilus aequodonenia)两个稀有物种在内的共计9个物种为该地区首次报道, 丰富了物种分布记录。结合历史资料, 黑竹沟地区共记录小型兽类43种, 隶属4目9科28属。在43种小型兽类中, 东洋界物种37种, 占绝对优势(86%), 分布型以喜马拉雅-横断山型占优, 为18种(占东洋界48.6%)。本次调查捕获的21种小型兽类中, 群落优势种为中华姬鼠(Apodemus draco, 33.2%)、北社鼠(Niviventer confucianus, 21.3%)和中华绒鼠(Eothenomys chinensis, 12.7%)。随着海拔上升, 群落优势种组成发生变化, 由北社鼠 + 中华姬鼠 + 针毛鼠(Niviventer fulvescens) + 短尾鼩(Anourosorex squamipes)群落, 转变为中华绒鼠 + 中华姬鼠 + 凉山沟牙田鼠(Proedromys liangshanensis) + 西南绒鼠(Eothenomys custos)群落。群落物种区系的分布型组成随着海拔升高而发生变化, 喜马拉雅-横断山型物种随海拔升高所占比例增大; 分布于喜马拉雅-横断山的特有种分布的下限、中点和上限平均海拔都高于非特有种, 且特有种和非特有种的中点和下限平均海拔差异显著(n = 21, df = 19, P = 0.013; n = 21, df = 19, P < 0.01), 说明该区域物种具有明显的东洋界特征, 中高海拔主要由特有种构成。本研究丰富了黑竹沟地区小型兽类及群落多样性的数据资料, 有利于该地区物种多样性的研究和保护。 相似文献
78.
Jennifer L. Chandler Timothy R. Van Deelen Nathan P. Nibbelink John L. Orrock 《Ecology and evolution》2020,10(14):7145-7156
Because most tree species recruit from seeds, seed predation by small‐mammal granivores may be important for determining plant distribution and regeneration in forests. Despite the importance of seed predation, large‐scale patterns of small‐mammal granivory are often highly variable and thus difficult to predict. We hypothesize distributions of apex predators can create large‐scale variation in the distribution and abundance of mesopredators that consume small mammals, creating predictable areas of high and low granivory. For example, because gray wolf (Canis lupus) territories are characterized by relatively less use by coyotes (C. latrans) and greater use by foxes (Vulpes vulpes, Urocyon cinereoargentus) that consume a greater proportion of small mammals, wolf territories may be areas of reduced small‐mammal granivory. Using large‐scale, multiyear field trials at 22 sites with high‐ and low‐wolf occupancy in northern Wisconsin, we evaluated whether removal of seeds of four tree species was lower in wolf territories. Consistent with the hypothesized consequences of wolf occupancy, seed removal of three species was more than 25% lower in high‐wolf‐occupancy areas across 2 years and small‐mammal abundance was more than 40% lower in high‐wolf areas during one of two study years. These significant results, in conjunction with evidence of seed consumption in situ and the absence of significant habitat differences between high‐ and low‐wolf areas, suggest that top‐down effects of wolves on small‐mammal granivory and seed survival may occur. Understanding how interactions among carnivores create spatial patterns in interactions among lower trophic levels may allow for more accurate predictions of large‐scale patterns in seed survival and forest composition. 相似文献
79.
80.
《Critical reviews in biochemistry and molecular biology》2013,48(6):502-530
Our understanding of the detailed mechanism of action of cytokine and growth factor receptors – and particularly our quantitative understanding of the link between structure, mechanism and function – lags significantly behind our knowledge of comparable functional protein classes such as enzymes, G protein-coupled receptors, and ion channels. In particular, it remains controversial whether such receptors are activated by a mechanism of ligand-induced oligomerization, versus a mechanism in which the ligand binds to a pre-associated receptor dimer or oligomer that becomes activated through subsequent conformational rearrangement. A major limitation to progress has been the relative paucity of methods for performing quantitative mechanistic experiments on unmodified receptors expressed at endogenous levels on live cells. In this article, we review the current state of knowledge on the activation mechanisms of cytokine and growth factor receptors, critically evaluate the evidence for and against the different proposed mechanisms, and highlight other key questions that remain unanswered. New approaches and techniques have led to rapid recent progress in this area, and the field is poised for major advances in the coming years which promise to revolutionize our understanding of this large and biologically and medically important class of receptors. 相似文献