Nuclear factor of activated T cells regulates transcription of the surfactant protein D gene (Sftpd) via direct interaction with thyroid transcription factor-1 in lung epithelial cells
Nuclear factor of activated T cells regulates transcription of the surfactant protein D gene (Sftpd) via direct interaction with thyroid transcription factor-1 in lung epithelial cells
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DOI：
10.1074/jbc.m404296200
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发表时间：
2004-08-13
影响因子：
4.8
通讯作者：
Whitsett, JA
中科院分区：
文献类型：
--
作者：
Davé, V;Childs, T;Whitsett, JA
表面活性剂蛋白D （SP-D）在宿主防御、表面活性剂稳态和肺免疫调节中起着至关重要的作用。在这里，我们确定了活化T细胞核因子（nfat）在调节小鼠SP-D基因（Sftpd）转录中的作用。在sfpd启动子中发现了一种由nfat或钙调磷酸酶调节且对环孢素敏感的nfat依赖性增强子。Ionomycin和phorbol 12-肉豆蔻酸酯13-乙酸进一步增加了这种增强剂的活性，而VIVIT，一种有效的NFAT抑制剂肽，选择性地干扰了钙调磷酸酶-NFAT相互作用并破坏了增强剂的功能。凝胶超移和DNA酶I保护实验鉴定了sfpd启动子中结合NFAT的DNA元件。在胚胎和成年小鼠肺上皮中检测到钙调磷酸酶和NFATc3蛋白，NFATc3 mRNA表达谱在永生化小鼠肺上皮细胞和肺泡上皮II型细胞中相似。NFATc3和TTF-1激活Sftpd启动子，协同转录，共同免疫沉淀小鼠肺上皮细胞，并在体外物理相互作用。在肺呼吸上皮细胞中发现了钙调神经磷酸酶/NFAT通路的成分，这些成分可能会增加sfpd启动子上多蛋白转录复合物的快速组装，从而诱导SP-D表达。
Surfactant protein D (SP-D) plays critical roles in host defense, surfactant homeostasis, and pulmonary immunomodulation. Here, we identify a role of nuclear factor of activated T cells (NFATs) in regulation of murine SP-D gene (Sftpd) transcription. An NFAT-dependent enhancer modulated by NFATs or calcineurin and sensitive to cyclosporin was identified in the Sftpd promoter. Ionomycin and phorbol 12-myristate 13-acetate further increased the activity of this enhancer, whereas VIVIT, a potent NFAT inhibitor peptide, selectively interfered with the calcineurin-NFAT interaction and abolished enhancer function. Gel supershift and DNase I protection assays identified DNA elements that bind NFAT in the Sftpd promoter. Calcineurin and NFATc3 proteins were detected in the embryonic and adult mouse lung epithelium, and the mRNA expression profiles of the NFATs were similar in immortalized mouse lung epithelial cells and alveolar epithelial type II cells. NFATc3 and TTF-1 activated the Sftpd promoter, synergized transcription, co-immunoprecipitated from mouse lung epithelial cells, and physically interacted in vitro. Components of the calcineurin/NFAT pathway were identified in respiratory epithelial cells of the lung that potentially augment rapid assembly of a multiprotein transcription complex on Sftpd promoter inducing SP-D expression.