Mechanical stretch is a highly selective regulator of gene expression in human bladder smooth muscle cells
Mechanical stretch is a highly selective regulator of gene expression in human bladder smooth muscle cells
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DOI：
10.1152/physiolgenomics.00181.2004
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发表时间：
2004-12-15
影响因子：
4.6
通讯作者：
Freeman, MR
中科院分区：
文献类型：
--
作者：
Adam, RM;Eaton, SH;Freeman, MR
应用机械刺激已被证明可以改变膀胱平滑肌细胞（SMC）中的基因表达。到目前为止，只有有限数量的“拉伸反应”基因在这种细胞类型已被报道。我们采用寡核苷酸芯片技术鉴定了原代培养的人膀胱平滑肌细胞在重复机械刺激4 h后的牵张敏感基因。使用微阵列显著性分析（SAM）评估拉伸和非拉伸细胞之间的差异基因表达。在拉伸后，11，731个表达基因中的20个（类似于0.17%）的表达改变> 2倍，其中19个基因被诱导，一个基因（FGF-9）被抑制。使用实时RT-PCR，我们独立测试了15个基因对伸展和血小板衍生生长因子-BB（PDGF-BB）（膀胱SMC的另一种肥大刺激）的反应性。在两种刺激下，13个基因的表达增加，1个基因（FGF-9）减少，1个基因不变。使用膀胱扩张的离体大鼠模型评估六种转录物（HB-EGF、BMP-2、考克斯-2、LIF、PAR-2和FGF-9）。HB-EGF、BMP-2、考克斯-2、LIF和PAR-2随着离体膀胱牵拉而增加，而FGF-9减少，与体外观察到的表达变化一致。使用FIRED算法的微阵列数据的计算机分析鉴定了c-jun、AP-1、ATF-2和神经纤维蛋白-1（NF-1）作为拉伸信号的潜在转录介质。此外，13个拉伸响应基因的9个启动子含有AP-1结合位点。这些观察结果表明，在膀胱平滑肌细胞的基因表达的高度选择性调节拉伸。此外，他们认为，机械和生长因子的信号汇聚在共同的转录调控，包括AP-1家族的成员。
Application of mechanical stimuli has been shown to alter gene expression in bladder smooth muscle cells (SMC). To date, only a limited number of "stretch-responsive" genes in this cell type have been reported. We employed oligonucleotide arrays to identify stretch-sensitive genes in primary culture human bladder SMC subjected to repetitive mechanical stimulation for 4 h. Differential gene expression between stretched and nonstretched cells was assessed using Significance Analysis of Microarrays (SAM). Expression of 20 out of 11,731 expressed genes ( similar to 0.17%) was altered > 2-fold following stretch, with 19 genes induced and one gene (FGF-9) repressed. Using real-time RT-PCR, we tested independently the responsiveness of 15 genes to stretch and to platelet-derived growth factor-BB (PDGF-BB), another hypertrophic stimulus for bladder SMC. In response to both stimuli, expression of 13 genes increased, 1 gene (FGF-9) decreased, and 1 gene was unchanged. Six transcripts (HB-EGF, BMP-2, COX-2, LIF, PAR-2, and FGF-9) were evaluated using an ex vivo rat model of bladder distension. HB-EGF, BMP-2, COX-2, LIF, and PAR-2 increased with bladder stretch ex vivo, whereas FGF-9 decreased, consistent with expression changes observed in vitro. In silico analysis of microarray data using the FIRED algorithm identified c-jun, AP-1, ATF-2, and neurofibromin-1 (NF-1) as potential transcriptional mediators of stretch signals. Furthermore, the promoters of 9 of 13 stretch-responsive genes contained AP-1 binding sites. These observations identify stretch as a highly selective regulator of gene expression in bladder SMC. Moreover, they suggest that mechanical and growth factor signals converge on common transcriptional regulators that include members of the AP-1 family.