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151.
Viral infection induces the initiation of antiviral effectors and cytokines which are critical mediators of innate antiviral responses.The critical molecular determinants are responsible for triggering an appropriate immune response. Long noncoding RNAs(lncRNAs) have emerged as new gene modulators involved in various biological processes, while how lncRNAs operate in lower vertebrates are still unknown. Here, we discover a long noncoding RNA, termed antiviral-associated long noncoding RNA(AANCR), as a novel regulator for innate antiviral responses in teleost fish. The results indicate that fish MITA plays an essential role in host antiviral responses and inhibition of Siniperca chuatsi rhabdovirus(SCRV) production. miR-210 reduces MITA expression and suppress MITA-mediated antiviral responses, which may help viruses evade host antiviral responses. Further,AANCR functions as a competing endogenous RNA(ceRNA) for miR-210 to control protein abundance of MITA, thereby inhibiting SCRV replication and promoting antiviral responses. Our data not only shed new light on understanding the function role of lncRNA in biological processes in teleost fish, but confirmed the hypothesis that ceRNA networks exist widely in vertebrates. 相似文献
152.
Yang Teng Shi Yu Zhu Jun Zhao Chang Wang Jianmei Liu Zhiyong Fu Xiao Liu Xu Yan Jiangwei Yuan Meiqing Chu Haiyan 《中国科学:生命科学英文版》2021,64(9):1546-1559
Urban soils harbor billions of bacterial cells and millions of species. However, the distribution patterns and assembly processes of bacterial communities remain largely uncharacterized in urban soils. It is also unknown if we can use the bacteria to track soil sources to certain cities and districts. Here, Illumina MiSeq sequencing was used to survey soil bacterial communities from 529 random plots spanning 61 districts and 10 major cities in China. Over a 3,000 km range, community similarity declined with increasing geographic distance(Mantel r=0.62), and community composition was clustered by city(R~2=0.50). Within cities(100 km), the aforementioned biogeographic patterns were weakened. Process analysis showed that homogenizing dispersal and dispersal limitation dominated soil bacterial assembly at small and large spatial scales, respectively. Accordingly, the probabilities of accurately tracking random soil sources to certain cities and districts were 90.0% and 66.7%, respectively. When the tested samples originated from cities that were more than 1,265 km apart, the soil sources could be identified with nearly 100% accuracy. Overall, this study demonstrates the strong distance-decay relationship and the clear geographic zoning of urban soil bacterial communities among cities. The varied importance of different community assembly processes at multiple spatial scales strongly affects the accuracy of microbial source tracking. 相似文献
153.
MicroRNAs (miRNAs)是一类非编码的小分子单链RNA,通过与靶基因的mRNA结合,抑制mRNA的翻译,参与多种生物学过程.本实验室前期通过高通量测序发现90日龄牦牛胚胎的背最长肌中miR-383的表达量显著高于成年牦牛.为探究miR-383在牦牛骨骼肌发育中的分子功能和机制,本研究对miR-383的靶基因进行预测,并进行生物信息学分析.通过TargetScan、miRDB和miRanda 3个软件预测了miR-383的靶基因,然后合并miRTarbase数据库中已被证实的靶基因作为基因集,分别用DAVID和KOBAS3.0在线软件对基因集进行功能注释(GO分析)和Pathway信号通路富集分析.结果 表明,牦牛miR-383序列在各物种间高度保守,靶基因功能富集于CD8阳性T细胞增殖的调控、核糖核蛋白复合物定位和负调控T细胞分化等生物学过程.信号通路分析发现靶基因的信号通路显著富集于PI3K-Ak、AMPK、FoxO和Focal adhesion等与肌肉发育相关的信号通路中.该研究结果将为miR-383功能及调控机制的深入研究提供参考依据,也为解析牦牛肌肉发育的分子机制提供新的研究方向. 相似文献
154.
Pei Jie Xiong Lin Bao Pengjia Chu Min Yan Ping Guo Xian 《Probiotics and antimicrobial proteins》2021,13(3):873-884
Probiotics and Antimicrobial Proteins - Lactoferricin (Lfcin) is a potent antibacterial peptide derived from lactoferrin by pepsin hydrolysis. It was hypothesized that structural transformation of... 相似文献
155.
Cheng Chu Gang Xu Xiaocong Li Zuowei Duan Lihong Tao Hongxia Cai Ming Yang Xinjiang Zhang Bin Chen Yanyu Zheng Hongcan Shi Xiaoyu Li 《Journal of cellular and molecular medicine》2021,25(1):110-119
Shear stress was reported to regulate the expression of AC007362, but its underlying mechanisms remain to be explored. In this study, to isolate endothelial cells of blood vessels, unruptured and ruptured intracranial aneurysm (IA) tissues were collected from IA patients. Subsequently, quantitative real-time PCR (qRT-PCR), Western blot and luciferase assay were performed to investigate the relationships between AC007362, miRNAs-493 and monocyte chemoattractant protein-1 (MCP-1) in human umbilical vein endothelial cells (HUVECs) exposed to shear stress. Reduced representation bisulphite sequencing (RRBS) was performed to assess the level of DNA methylation in AC007362 promoter. Accordingly, AC007362 and MCP-1 were significantly up-regulated while miR-493 was significantly down-regulated in HUVECs exposed to shear stress. AC007362 could suppress the miR-493 expression and elevate the MCP-1 expression, and miR-493 was shown to respectively target AC007362 and MCP-1. Moreover, shear stress in HUVECs led to the down-regulated DNA methyltransferase 1 (DNMT1), as well as the decreased DNA methylation level of AC007362 promoter. Similar results were also observed in ruptured IA tissues when compared with unruptured IA tissues. In conclusion, this study presented a deep insight into the operation of the regulatory network of AC007362, miR-493 and MCP-1 upon shear stress. Under shear stress, the expression of AC007362 was enhanced by the inhibited promoter DNA methylation, while the expression of MCP-1 was enhanced by sponging the expression of miR-493. 相似文献
156.
Ng Chu Xin Le Cheng Foh Tor Yin Sim Lee Sau Har 《International journal of peptide research and therapeutics》2021,27(4):2757-2775
International Journal of Peptide Research and Therapeutics - Bioactive peptides have emerged as promising therapeutic alternatives in pharmaceutical industry, especially to fight cancer. Here we... 相似文献
157.
Ecosystems - In arid environments, shade provided by vegetation forms the crux of many facilitation pathways by providing other organisms with relief from high levels of solar radiation and extreme... 相似文献
158.
溪流鱼类多样性沿着河流纵向梯度的空间分布规律已得到大量报道, 但这些研究大多聚焦基于物种组成的分类α多样性, 而有关分类β多样性和功能多样性的纵向梯度分布规律及其对人类干扰的响应研究较少。本文以青弋江上游3条人为干扰程度不同的河源溪流为研究区域, 比较研究了人为干扰对溪流鱼类功能α和β多样性及其纵向梯度分布格局的影响。结果显示, 人类干扰改变了河源溪流鱼类功能多样性的纵向梯度格局——由线性变化变为二项式分布。此外, 我们发现, 人为干扰导致土著种被本地入侵种取代, 且较强的土地利用和水污染排放可能增大环境的不连续性, 而群落周转和嵌套变化往往取决于环境的变化。尽管功能β多样性由嵌套成分主导, 但周转成分占比相对于人为干扰较小的溪流而言明显增加。人为干扰显著改变了受干扰溪流鱼类的物种组成和功能多样性, 且功能多样性的纵向梯度格局在不同的多样性指标上存在差异。本研究强调, 在评估人为干扰下多样性的变化时, 需要从多方面考虑, 包括空间尺度和多样性指标等。 相似文献
159.
Xiaoqian Liu Yuanfeng Zhang Kaimin Li Yinghui Liu Junqing Xu Junjie Ma Licai An Hui Wang Xiaoxia Chu 《Translational oncology》2021,14(7):101085
Refractory/relapsed B cell lymphoma patients who received the available anti-CD19 chimeric antigen receptor (CAR) T cells may still experience a short duration of remission. Here in this study, we evaluated the safety and efficacy of a novel dominant-negative programmed cell death-1 (PD-1) armored anti-CD19 CAR T cells. A total of 9 patients (including 4 diffuse large B cell lymphomas, DLBCL, 2 transformed follicular lymphomas, TFL, and 3 follicular lymphomas, FL) received the novel CAR T cells infusion at a dose of more than 1 × 106/kg. Grade ≥ 3 cytokine release syndrome (CRS) and neurotoxicity were observed in 11.1% (n = 1/9) and 11.1% (n = 1/9) of patients, respectively. The overall response rate (ORR) was 77.8% (n = 7/9) and complete response (CR) rate was 55.6% (n = 5/9). Two patients have ongoing CR (all at 20+ months). CAR T cells expanded after infusion and continued to be detectable at 12+ months in patients with ongoing CR. This novel CD19-CAR T cell was safe and effective with durable remissions in patients with refractory/relapsed B cell lymphoma. 相似文献
160.