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关键词： DOSAGE COMPENSATION   PROTEIN   MOF   DOMAIN   DNA   DROSOPHILA   BINDING   IDENTIFICATION   TRANSCRIPTION   ACETYLATION  

摘要： The methyl-lysine readers plant homeodomain finger protein 20 (PHF20) and its homolog PHF20-like protein 1 (PHF20L1) are known components of the nonspecific lethal (NSL) complex that regulates gene expression through its histone acetyltransferase activity. In the current model, both PHF homologs coexist in the same NSL complex, although this was not formally tested; nor have the functions of PHF20 and PHF20L1 regarding NSL complex integrity and transcriptional regulation been investigated. Here, we perform an in-depth biochemical and functional characterization of PHF20 and PHF20L1 in the context of the NSL complex. Using mass spectrometry, genome-wide chromatin analysis, and proteindomain mapping, we identify the existence of two distinct NSL complexes that exclusively contain either PHF20 or PHF20L1. We show that the C-terminal domains of PHF20 and PHF20L1 are essential for complex formation with NSL, and the Tudor 2 domains are required for chromatin binding. The genome-wide chromatin landscape of PHF20-PHF20L1 shows that these proteins bind mostly to the same genomic regions, at promoters of highly expressed/housekeeping genes. Yet, deletion of PHF20 and PHF20L1 does not abrogate gene expression or impact the recruitment of the NSL complex to those target gene promoters, suggesting the existence of an alternative mechanism that compensates for the transcription of genes whose sustained expression is important for critical cellular functions. This work shifts the current paradigm and lays the foundation for studies on the differential roles of PHF20 and PHF20L1 in regulating NSL complex activity in physiological and diseases states.

摘要： 1 她听到他说,他热爱手洗. 她忍不住问:手洗,你热爱手洗? 她看到他拿起她的袜子,凑到鼻子下嗅了三下,没皱眉头.她有些不好意思,从身后抱住了他.她念旧,喜欢买材质好的袜子,这样就可以穿三四年.但长筒丝袜不行,还穿不过一年夏天.这是一双棉袜,白色,中筒,秋天穿.

关键词： 公路   桥梁连接   伸缩缝设计   问题探讨  

摘要： 随着经济的发展,我国的桥梁与道路施工技术有了进一步的提高.关于我国的公路与桥梁问题显然已经成为施工设计当中的重点以及难点问题之一.为了推进公路与桥梁问题的解决,本文主要探讨的就是关于连接处的伸缩缝设计问题,以保证公路与桥梁道路建设得更加完美,加强道路施工等方面具体问题的解决.

关键词： 公路桥梁   工程施工   伸缩缝施工   施工工艺  

摘要： 在公路桥梁中运用伸缩缝施工工艺是非常重要的,但是由于整体施工环境较为复杂,存在诸多的影响因素,因此要加强对公路桥梁施工中伸缩缝施工模式的优化以及调整,推动公路建设行业的稳定发展.为此,结合伸缩缝施工在公路桥梁中的应用价值,以及主要的施工类型,总结了伸缩缝施工工艺中的质量控制措施,提出了伸缩缝施工的优化策略.在伸缩缝施工时,要严格按照施工流程和标准进行日常操作,并且还要加强对周边情况的全面分析,提高后续的施工效果.

关键词： DEVELOPMENTAL ABNORMALITIES   MTORC1   GENE   ACTIVATION   FOLLICULIN   GTPASES   CLONING   SFMBT2  

摘要： Placenta hyperplasia is commonly observed in cloned animals and is believed to impede the proper development of cloned embryos. However, the mechanism underlying this phenomenon is largely unknown. Here, we show that placenta hyperplasia of cloned mouse embryos occurs in both middle and late gestation. Interestingly, restoring paternal-specific expression of an amino acid transporter Slc38a4, which loses maternal H3K27me3-dependent imprinting and becomes biallelically expressed in cloned placentae, rescues the overgrowth of cloned placentae at late gestation. Molecular analyses reveal that loss of Slc38a4 imprinting leads to over-activation of the mechanistic target of rapamycin complex 1 (mTORC1) signaling pathway in cloned placentae, which is likely due to the increased amino acids transport by SLC38A4. Collectively, our study not only reveals loss of Slc38a4 imprinting is responsible for overgrowth of cloned placentae at late gestation but also suggests the underlying mechanism involves increased amino acid transport and over-activation of mTORC1.