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191.
Lihua Qu Yi Li Chao Chen Tong Yin Qian Fang Yijin Zhao Wenting Lv Ziqi Liu Yangye Chen Li Shen 《Cell death & disease》2022,13(8)
Acute lung injury (ALI) is a potentially life-threatening, devastating disease with an extremely high rate of mortality. The underlying mechanism of ALI is currently unclear. In this study, we aimed to confirm the hub genes associated with ALI and explore their functions and molecular mechanisms using bioinformatics methods. Five microarray datasets available in GEO were used to perform Robust Rank Aggregation (RRA) to identify differentially expressed genes (DEGs) and the key genes were identified via the protein-protein interaction (PPI) network. Lipopolysaccharide intraperitoneal injection was administered to establish an ALI model. Overall, 40 robust DEGs, which are mainly involved in the inflammatory response, protein catabolic process, and NF-κB signaling pathway were identified. Among these DEGs, we identified two genes associated with ALI, of which the CAV-1/NF-κB axis was significantly upregulated in ALI, and was identified as one of the most effective targets for ALI prevention. Subsequently, the expression of CAV-1 was knocked down using AAV-shCAV-1 or CAV-1-siRNA to study its effect on the pathogenesis of ALI in vivo and in vitro. The results of this study indicated that CAV-1/NF-κB axis levels were elevated in vivo and in vitro, accompanied by an increase in lung inflammation and autophagy. The knockdown of CAV-1 may improve ALI. Mechanistically, inflammation was reduced mainly by decreasing the expression levels of CD3 and F4/80, and activating autophagy by inhibiting AKT/mTOR and promoting the AMPK signaling pathway. Taken together, this study provides crucial evidence that CAV-1 knockdown inhibits the occurrence of ALI, suggesting that the CAV-1/NF-κB axis may be a promising therapeutic target for ALI treatment.Subject terms: Cell signalling, Respiratory tract diseases 相似文献
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定量生育期内植物光合碳在植物组织-土壤的分配规律,对于理解全球碳循环有着重要意义。采用~(13)C-CO_2脉冲标记结合室内培养,通过元素分析仪-稳定同位素联用(Flash HT-IRMS)分析植物各部分及土壤δ~(13)C值,比较了不同生育期下水稻光合碳在不同组织间的分配规律,并量化了水稻光合碳向土壤碳库的转移。结果表明:(1)水稻地上部和根系干物质量随水稻生育期的增加而呈现递增趋势,不同的生育期表现为:分蘖期拔节期抽穗期扬花期成熟期。而整个生育期的根冠比为0.2—0.4,分蘖期的根冠比最高,随着水稻生育期的增加而递减,到抽穗期以后根冠比稳定在0.2左右。(2)脉冲标记6h后,水稻地上部和地下部(根系)的δ~(13)C值在-25.52‰—-28.33‰,不同器官的δ~(13)C值存在明显分馏效应,且趋势基本一致,即茎杆(籽粒)叶片(根系);这种由于水稻生育期特性导致的各器官碳同位素分馏的现象,可用于指示不同生育期下水稻光合碳的分配和去向。(3)不同生育期~(13)C-光合碳在植物-土壤系统的分配规律不同,生长前期光合碳向根系及土壤中分配的比例高,具有较强的碳汇能力,而随生育期光合碳在根系及土壤中的分配比例呈下降趋势,但积累量不断增加。(4)不同生育期~(13)C光合碳在水稻-土壤系统中的分配比例差异明显。水稻分蘖期有近30%光合碳用于根系建成并部分通过根系分泌物进入土壤有机碳库(10%),而到成熟期则向籽粒中分配较多,而且光合碳在土壤中的分配比例也随生育期呈下降趋势。研究结果对稻田土壤有机碳循环过程和调控机制的揭示具有重要的理论意义。 相似文献
194.
工业酵母抗逆机理研究进展 总被引:3,自引:2,他引:1
工业酵母利用木质纤维素等生物质资源发酵生产醇、酮、醛、酸等各种化合物,是解决人类面临的不可再生资源和能源危机的重要途径,这激发了人们对木质纤维素水解液为原料和环保节能型浓醪发酵技术的极度关注。然而高浓度底物、产物、渗透压、木质纤维素水解液中抑制性物质、发酵过程温度的提高均会抑制微生物生长代谢及发酵性能,这是发酵行业"瓶颈"问题。本文简述了渗透压、温度及抑制性物质对酵母细胞生长的危害,并从胞内稳态平衡、分子水平等方面着重叙述工业酵母对渗透压、温度及抑制性物质的抗逆机制研究进展。 相似文献
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Chengcheng Liang Xiong Xiong Rongwei Cui Yuanxiao Hong Xin Liu Guoru Zhao Lizi Ye Shuxin Qu 《仿生工程学报(英文版)》2021,18(4):927-943
The aim of this study was to reconstruct surface porous structure with hundreds of micrometers and then bio-mineralize Sr-doped Calcium Phosphate(Sr-doped CaP)o... 相似文献
197.
本研究以高原鳅属6个群体共82尾个体的线粒体DNA D-loop高变区为标记,采用分子生物信息学方法分析其遗传多样性及系统发育关系.结果表明,在570 bp的mtDNA D-loop中共检测到149个多态位点,由此界定了 39个单倍型.在6个群体中,单倍型多样度(Hd)由高到低依次为细尾高原鳅(T.stenura)(0... 相似文献
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CRISPR/Cas12a is a single effector nuclease that, like CRISPR/Cas9, has been harnessed for genome editing based on its ability to generate targeted DNA double strand breaks (DSBs). Unlike the blunt-ended DSB generated by Cas9, Cas12a generates sticky-ended DSB that could potentially aid precise genome editing, but this unique feature has thus far been underutilized. In the current study, we found that a short double-stranded DNA (dsDNA) repair template containing a sticky end that matched one of the Cas12a-generated DSB ends and a homologous arm sharing homology with the genomic region adjacent to the other end of the DSB enabled precise repair of the DSB and introduced a desired nucleotide substitution. We termed this strategy ‘Ligation-Assisted Homologous Recombination’ (LAHR). Compared to the single-stranded oligo deoxyribonucleotide (ssODN)-mediated homology directed repair (HDR), LAHR yields relatively high editing efficiency as demonstrated for both a reporter gene and endogenous genes. We found that both HDR and microhomology-mediated end joining (MMEJ) mechanisms are involved in the LAHR process. Our LAHR genome editing strategy, extends the repertoire of genome editing technologies and provides a broader understanding of the type and role of DNA repair mechanisms involved in genome editing. 相似文献