BackgroundMicroRNA (miRNA) and messenger RNA (mRNA) expression differs in cystic fibrosis (CF) versus non-CF bronchial epithelium. Here, the role of miRNA in basal regulation of the transcription factor ATF6 was investigated in bronchial epithelial cells in vitro and in vivo.MethodsUsing in silico analysis, miRNAs predicted to target the 3′untranslated region (3′UTR) of the human ATF6 mRNA were identified.ResultsThree of these miRNAs, miR-145, miR-221 and miR-494, were upregulated in F508del-CFTR homozygous CFBE41o- versus non-CF 16HBE14o- bronchial epithelial cells and also in F508del-CFTR homozygous or heterozygous CF (n = 8) versus non-CF (n = 9) bronchial brushings. ATF6 was experimentally validated as a molecular target of these miRNAs through the use of a luciferase reporter vector containing the full-length 3′UTR of ATF6. Expression of ATF6 was observed to be decreased in CF both in vivo and in vitro. miR-221 was also predicted to regulate murine ATF6, and its expression was significantly increased in native airway tissues of 6-week-old βENaC-overexpressing transgenic mice with CF-like lung disease versus wild-type littermates.ConclusionsThese results implicate miR-145, miR-221 and miR-494 in the regulation of ATF6 in CF bronchial epithelium, with miR-221 demonstrating structural and functional conservation between humans and mice. The altered miRNA expression evident in CF bronchial epithelial cells can affect expression of transcriptional regulators such as ATF6.

中文翻译：

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miRNA-221 在囊性纤维化气道上皮细胞中升高并调节 ATF6 的表达

背景微RNA (miRNA) 和信使RNA (mRNA) 在囊性纤维化(CF) 与非CF 支气管上皮中的表达不同。在这里，在体外和体内支气管上皮细胞中研究了 miRNA 在转录因子 ATF6 基础调节中的作用。 方法使用计算机分析，预测 miRNA 靶向人 ATF6 mRNA 的 3' 非翻译区 (3'UTR)结果这些 miRNA 中的三种，miR-145、miR-221 和 miR-494，在 F508del-CFTR 纯合 CFBE41o- 与非 CF 16HBE14o- 支气管上皮细胞以及 F508del-CFTR 纯合 CF 杂合（或= 8) 与非 CF (n = 9) 支气管刷牙。通过使用包含 ATF6 全长 3'UTR 的荧光素酶报告载体，ATF6 被实验验证为这些 miRNA 的分子靶标。在体内和体外均观察到 ATF6 的表达在 CF 中降低。还预测 miR-221 可调节鼠 ATF6，其表达在 6 周龄过表达 βENaC 的 CF 样肺病转基因小鼠与野生型同窝仔鼠的天然气道组织中显着增加。结论这些结果暗示 miR-145 、miR-221和miR-494在CF支气管上皮中ATF6的调节中，miR-221证明人和小鼠之间的结构和功能保守。CF 支气管上皮细胞中明显改变的 miRNA 表达会影响转录调节因子的表达，如 ATF6。并且其在 6 周龄 βENaC 过表达的 CF 样肺病转基因小鼠的自然气道组织中的表达与野生型同窝仔相比显着增加。结论这些结果表明 miR-145、miR-221 和 miR-494 参与调控CF 支气管上皮中 ATF6 的表达，miR-221 证明了人和小鼠之间的结构和功能保守性。CF 支气管上皮细胞中明显改变的 miRNA 表达会影响转录调节因子的表达，如 ATF6。并且其在 6 周龄 βENaC 过表达的 CF 样肺病转基因小鼠的自然气道组织中的表达显着增加。 CF 支气管上皮中 ATF6 的表达，miR-221 证明了人和小鼠之间的结构和功能保守性。CF 支气管上皮细胞中明显改变的 miRNA 表达会影响转录调节因子的表达，如 ATF6。