Pax-6 expression and activity are induced in the reepithelializing cornea and control activity of the transcriptional promoter for matrix metalloproteinase gelatinase B.
Pax-6 expression and activity are induced in the reepithelializing cornea and control activity of the transcriptional promoter for matrix metalloproteinase gelatinase B.
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DOI：
10.1006/dbio.2000.9694
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发表时间：
2000-06
影响因子：
2.7
通讯作者：
J. Sivak;Royce Mohan;W. B. Rinehart;Pin-Xian Xu;Richard L. Maas;M. Fini
中科院分区：
文献类型：
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作者：
J. Sivak;Royce Mohan;W. B. Rinehart;Pin-Xian Xu;Richard L. Maas;M. Fini
最近的证据支持这样的想法，即基质金属蛋白酶（MMPs）作为胚胎和成人组织重塑事件的形态发生调节剂。MMP活性主要在基因表达水平上受到控制。在最近的一项研究中，我们在转基因小鼠中表征了MMP基因明胶酶B（gelB）的转录启动子，证明了需要-522和+19之间的DNA序列才能获得适当的活性。在这项研究中，我们调查了gelB启动子活性在发育中的眼睛和再上皮化的成人角膜所需的因素。Pax-6是一个同源框和配对结构域转录因子，在控制眼睛发育的基因层次结构的顶部起作用。Pax-6也在成人眼中表达。我们在这里表明，Pax-6的组织表达模式与gelB启动子活性在发育和成人眼广泛重叠。此外，观察到Pax-6在修复角膜上皮中上调，gelB启动子活性也是如此。在细胞培养转染实验中，我们确定了两个启动子区域介导的阳性反应Pax-6。通过电泳迁移率变动分析，我们进一步确定了两个Pax-6的结合位点在这些响应区域，并证明直接的Pax-6配对域与这些网站之一的相互作用。这些数据表明Pax-6可能以眼睛特异性方式指导gelB表达的机制。
Recent evidence supports the idea that matrix metalloproteinases (MMPs) act as morphogenetic regulators in embryonic and adult events of tissue remodeling. MMP activity is controlled primarily at the level of gene expression. In a recent study we characterized the transcriptional promoter of the MMP gene, gelatinase B (gelB), in transgenic mice, demonstrating the requirement for DNA sequences between -522 and +19 for appropriate activity. In this study we investigated factors required for gelB promoter activity in the developing eye and reepithelializing adult cornea. Pax-6 is a homeobox and paired domain transcription factor that acts at the top of the hierarchy of genes controlling eye development. Pax-6 is also expressed in the adult eye. We show here that the tissue expression pattern of Pax-6 overlaps extensively with gelB promoter activity in the developing and adult eye. In addition Pax-6 is observed to be upregulated in repairing corneal epithelium, as is gelB promoter activity. In cell culture transfection experiments, we identified two promoter regions which mediate positive response to Pax-6. By electrophoretic mobility shift assay, we further pinpoint two Pax-6 binding sites within these response regions and demonstrate direct interaction of the Pax-6 paired domain with one of these sites. These data suggest a mechanism by which Pax-6 may direct gelB expression in an eye-specific manner.