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991.
Xiaoyu Qiu Guangliang Gao Lei Du Jing Wang Qi Wang Feiyun Yang Xiaorong Zhou Dingbiao Long Jinxiu Huang Zuohua Liu Renli Qi 《Current issues in molecular biology》2022,44(5):2038
Skeletal muscle satellite cells (SMSCs), which are multifunctional muscle-derived stem cells, can differentiate into adipocytes. Long-chain non-coding RNA (lncRNA) has diverse biological functions, including the regulation of gene expression, chromosome silencing, and nuclear transport. However, the regulatory roles and mechanism of lncRNA during adipogenic transdifferentiation in muscle cells have not been thoroughly investigated. Here, porcine SMSCs were isolated, cultured, and induced for adipogenic differentiation. The expressions of lncRNA and mRNA at different time points during transdifferentiation were analysed using RNA-seq analysis. In total, 1005 lncRNAs and 7671 mRNAs showed significant changes in expression at differential differentiation stages. Time-series expression analysis showed that the differentially expressed (DE) lncRNAs and mRNAs were clustered into 5 and 11 different profiles with different changes, respectively. GO, KEGG, and REACTOME enrichment analyses revealed that DE mRNAs with increased expressions during the trans-differentiation were mainly enriched in the pathways for lipid metabolism and fat cell differentiation. The genes with decreased expressions were mainly enriched in the regulation of cell cycle and genetic information processing. In addition, 1883 DE mRNAs were regulated by 193 DE lncRNAs, and these genes were related to the controlling in cell cycle mainly. Notably, three genes in the fatty acid binding protein (FABP) family significantly and continuously increased during trans-differentiation, and 15, 13, and 11 lncRNAs may target FABP3, FABP4, and FABP5 genes by cis- or trans-regulation, respectively. In conclusion, these studies identify a set of new potential regulator for adipogenesis and cell fate and help us in better understanding the molecular mechanisms of trans-differentiation. 相似文献
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993.
我国23个土壤磷素淋失风险评估Ⅱ.淋失临界值与土壤理化性质和磷吸附特性的关系 总被引:20,自引:0,他引:20
从13个省(市)采取23个耕地表层土壤,通过室内模拟试验测定其磷素淋失临界值和pH、有机质、<0.01mm、<0.002mm、交换性钙镁、活性铁铝、磷等温吸附特性等,以建立土壤磷素淋失临界值与土壤基本理化性质和磷吸附特性之间的关系.结果表明:土壤pH<6.0时,随土壤pH提高临界值增加,土壤pH与临界值之间呈显著的指数关系;而当土壤pH>6.0时,随土壤pH提高临界值减小,在pH6.5左右土壤磷素淋失临界值最高.土壤磷素淋失临界值与土壤有机质、活性铁(铝)、交换性钙之间存在显著的相关,而与交换性镁、CEC、<0.01mm、<0.002mm、K、Qm的相关性受土壤酸碱度影响.可以通过测定土壤有机质或活性铁的含量,来计算土壤磷素淋失临界值,评价土壤磷素淋失的风险.供试的23个土壤,除了采自湖北潜江的20号水稻土存在比较大的磷素淋失风险,其余土壤发生磷素淋失的风险很小. 相似文献
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用于生产重组蛋白药物的抗凋亡CHO宿主细胞株的建立 总被引:5,自引:0,他引:5
哺乳动物工程细胞在大规模培养生产重组蛋白时很容易发生细胞凋亡,从而导致生产过程提前终止,造成生产成本高昂。细胞代谢产物氨已被证明可以促进细胞凋亡,而线粒体膜整合蛋白Bcl-2可以通过促进线粒体膜完整性而抑制细胞凋亡。本实验应用谷氨酰胺合成酶加压系统在CHO工程细胞中高效表达中国仓鼠Bcl-2蛋白,使细胞具有抗凋亡能力的同时,利用谷氨酸和氨合成谷氨酰胺而有效降低培养基中氨的含量,从而达到抑制细胞凋亡的目的。 相似文献
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997.
麦套春棉主要害虫和天敌的生态位研究 总被引:5,自引:2,他引:5
调查了麦套着棉不同时期内,棉株上、中、下部棉蚜AphisgossypiiGover、棉叶螨TetranychustruncatusEhara、棉铃虫Helicoverpaarmigera(Hubner)和其主要天敌的数量。求得各期害虫与害虫、害虫与天敌、天敌与天敌之间的生态位宽度和重叠指数,并分析了它们彼此在空间上的竞争关系。 相似文献
998.
Detection of the synergetic effects between variants, such as single-nucleotide polymorphisms (SNPs), is crucial for understanding the genetic characters of complex diseases. Here, we proposed a two-step approach to detect differentially inherited SNP modules (synergetic SNP units) from a SNP network. First, SNP-SNP interactions are identified based on prior biological knowledge, such as their adjacency on the chromosome or degree of relatedness between the functional relationships of their genes. These interactions form SNP networks. Second, disease-risk SNP modules (or sub-networks) are prioritised by their differentially inherited properties in IBD (Identity by Descent) profiles of affected and unaffected sibpairs. The search process is driven by the disease information and follows the structure of a SNP network. Simulation studies have indicated that this approach achieves high accuracy and a low false-positive rate in the identification of known disease-susceptible SNPs. Applying this method to an alcoholism dataset, we found that flexible patterns of susceptible SNP combinations do play a role in complex diseases, and some known genes were detected through these risk SNP modules. One example is GRM7, a known alcoholism gene successfully detected by a SNP module comprised of two SNPs, but neither of the two SNPs was significantly associated with the disease in single-locus analysis. These identified genes are also enriched in some pathways associated with alcoholism, including the calcium signalling pathway, axon guidance and neuroactive ligand-receptor interaction. The integration of network biology and genetic analysis provides putative functional bridges between genetic variants and candidate genes or pathways, thereby providing new insight into the aetiology of complex diseases. 相似文献
999.
文[1]提出了单种生长的连续性文广义Logistic dx/dt=γx({K-x}/(K+px))其中γ>ο为种群的内禀生长率,K>0为环境容纳量,ν>-1表示种群对环境(包括营 相似文献
1000.