Cloning of rat laminin gamma 1-chain gene promoter reveals motifs for recognition of multiple transcription factors.
Cloning of rat laminin gamma 1-chain gene promoter reveals motifs for recognition of multiple transcription factors.
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大鼠层粘连蛋白 γ 1 链基因启动子的克隆揭示了识别多种转录因子的基序。
DOI：
10.1152/ajprenal.1997.273.3.f411
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
Bomsztyk,K
中科院分区：
文献类型：
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作者：
O'Neill,BC;Suzuki,H;Loomis,WP;Denisenko,O;Bomsztyk,K
我们先前已经表明，层粘连蛋白γ 1（层粘连蛋白B2）链mRNA水平在用细胞因子白细胞介素-1 β（IL-1 β）处理大鼠肾小球上皮细胞（GEC）时增加[C. A. Richardson，K. L.戈登，W。G. Cherer和K.波兹提克Am. J.Physiol.268（Renal Fluid Electrolyte Physiol.37）：F273-F278，1995]。IL-1 β诱导的层粘连蛋白γ 1链基因表达增加可能受到转录调节。由于层粘连蛋白γ 1-链基因启动子以前没有在大鼠中克隆，我们从大鼠基因组文库中克隆了该基因的5 '侧翼区。与人和鼠层粘连蛋白γ 1链基因启动子一样，相对于起始密码子，大鼠层粘连蛋白γ 1链基因片段从核苷酸-1104至+109跨越，富含“GC”并且缺乏TATA或CAAT盒。该大鼠层粘连蛋白γ 1链基因启动子区似乎含有至少两个转录起始位点，即，位置-169和-234。在GEC中的瞬时转染中，克隆到荧光素酶报告基因上游的-1104/+35和-1104/-15片段具有非常小的组成型活性，并且不对IL-1 β产生应答。与此形成鲜明对比的是，-1104/-234片段表现出组成型活性并且是IL-1 β应答性的。-1104/-234片段含有识别GEC核提取物中Sp1、BCN-1和ApoE-B1-AP 1 DNA结合活性的基序。总的来说，本研究的结果表明多种诱导型转录因子可能调节GEC中层粘连蛋白γ 1链基因启动子的活性。
We have previously shown that laminin gamma 1 (laminin B2)-chain mRNA levels increase in response to treatment of rat glomerular epithelial cells (GEC) with the cytokine interleukin-1 beta (IL-1 beta) [C. A. Richardson, K. L. Gordon, W. G. Couser, and K. Bomsztyk. Am. J. Physiol. 268 (Renal Fluid Electrolyte Physiol. 37): F273-F278, 1995]. IL-1 beta-induced increase in laminin gamma 1-chain gene expression is likely to be transcriptionally regulated. As the laminin gamma 1-chain gene promoter had not previously been cloned in the rat, we cloned the 5'-flanking region of this gene from a rat genomic library. Like the human and murine laminin gamma 1-chain gene promoters, the rat laminin gamma 1-chain gene fragment spanning from nucleotides -1104 to +109, relative to the start codon, is "GC" rich and lacks TATA or CAAT boxes. This rat laminin gamma 1-chain gene promoter region appears to contain at least two transcription initiation sites, i.e., position -169 and -234. In transient transfections in GEC, the -1104/+35 and -1104/-15 fragments cloned upstream of a luciferase reporter gene had very little constitutive activity and were not IL-1 beta responsive. In sharp contrast, a -1104/-234 fragment exhibited constitutive activity and was IL-1 beta responsive. The -1104/-234 fragment contains motifs that recognize Sp1, BCN-1, and ApoE-B1-AP1 DNA-binding activities in GEC nuclear extracts. Collectively, the results of this study suggest that multiple inducible transcription factors may regulate laminin gamma 1-chain gene promoter activity in GEC.