Hsp70 is required for optimal cell proliferation in mouse A6 mesoangioblast stem cells.
Hsp70 is required for optimal cell proliferation in mouse A6 mesoangioblast stem cells.
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DOI：
10.1042/bj20082309
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发表时间：
2009-07
期刊：
影响因子：
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通讯作者：
G. Turturici;F. Geraci;M. E. Candela;G. Cossu;G. Giudice;G. Sconzo
中科院分区：
文献类型：
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作者：
G. Turturici;F. Geraci;M. E. Candela;G. Cossu;G. Giudice;G. Sconzo
小鼠热休克蛋白Hsp70 （70 kDa热休克蛋白）优先受到热刺激或应激刺激的诱导。我们之前发现Hsp70在A6小鼠成血管干细胞中组成性表达，但其在这些细胞中的可能作用及其对基础转录的控制尚不清楚。在没有胁迫的情况下，Ku因子在体外能够结合HSE（热休克元件）共识序列，而在体内则与近端hsp70启动子结合。此外，我们发现hsp70的组成性转录依赖于Sp1（特异性蛋白1）和ga -结合蛋白与Ku因子等不同因子的协同相互作用，Ku因子结合HSE共识序列。我们用mRNA干扰法选择敲低的细胞克隆。这些细胞能够通过产生大量的Hsp70来应对热应激，并且产生与应激A6细胞相同数量的Hsp70。然而，严重Hsp70敲低的细胞复制时间较长，表明组成型Hsp70表达对增殖速度有影响。
Mouse Hsp70 (70 kDa heat shock protein) is preferentially induced by heat or stress stimuli. We previously found that Hsp70 is constitutively expressed in A6 mouse mesoangioblast stem cells, but its possible role in these cells and the control of its basal transcription remained unexplored. Here we report that in the absence of stress, Ku factor is able to bind the HSE (heat shock element) consensus sequence in vitro, and in vivo it is bound to the proximal hsp70 promoter. In addition, we show that constitutive hsp70 transcription depends on the co-operative interaction of different factors such as Sp1 (specificity protein 1) and GAGA-binding protein with Ku factor, which binds the HSE consensus sequence. We used mRNA interference assays to select knockdown cell clones. These cells were able to respond to heat stress by producing a large amount of Hsp70, and produced the same amount of Hsp70 as that synthesized by stressed A6 cells. However, severe Hsp70 knockdown cells had a longer duplication time, suggesting that constitutive Hsp70 expression has an effect on the rate of proliferation.