miR-326 Is Downstream of Sonic Hedgehog Signaling and Regulates the Expression of Gli2 and Smoothened
miR-326 Is Downstream of Sonic Hedgehog Signaling and Regulates the Expression of Gli2 and Smoothened
复制标题
DOI：
10.1165/rcmb.2013-0127oc
复制
发表时间：
2014-08-01
影响因子：
6.4
通讯作者：
Lu, Jining
中科院分区：
文献类型：
--
作者：
Jiang, Zhihua;Cushing, Leah;Lu, Jining
Sonic hedgehog（Shh）由胚胎肺上皮表达和分泌，并通过其受体Patched（Ptch）/Smoothened（Smo）和转录效应物Gli蛋白作用于邻近的间充质细胞。遗传学研究表明，Shh通路在小鼠肺发育中起着关键作用。然而，对胚胎肺中Shh下游的microRNAs（miRNAs）知之甚少。在此，我们通过下一代测序分析了用环巴胺（一种特异性Smo拮抗剂）或Smo激动剂处理的胚胎肺培养物中的miRNA。然后，我们进行了功能筛选，以检查这些miRNA中的一些是否可以通过Shh处理来调节Gli响应性荧光素酶的诱导。这些分析显示，miR-326及其宿主基因Arrestin beta 1的表达在胚胎肺间充质细胞中选择性富集，并且受到Shh活性的特异性影响。此外，功能分析显示，miR-326通过直接靶向Smo和Gli 2而充当Shh信号传导的负调节剂。总之，这些发现表明了一种新的miR-326负反馈回路在调节Shh信号传导的活性。
Sonic hedgehog (Shh) is expressed and secreted from the embryonic lung epithelium and acts on the adjacent mesenchymal cells via its receptor Patched (Ptch)/Smoothened (Smo) and transcriptional effectors Gli proteins. Genetic studies showed that the Shh pathway plays critical roles in mouse lung development. However, little is known about microRNAs (miRNAs) downstream of Shh in embryonic lungs. Here we profiled miRNAs in embryonic lung cultures treated with cyclopamine, a specific Smo antagonist or with Smo agonist by next-generation of sequencing. We then performed functional screening to examine whether some of these miRNAs can modulate the induction of Gli-responsive luciferase by Shh treatment. These analyses revealed that expression of miR-326 and its host gene, Arrestin beta 1, is selectively enriched in embryonic lung mesenchymal cells and is specifically influenced by Shh activity. Furthermore, functional analyses showed that miR-326 acts as a negative modulator for Shh signaling by directly targeting Smo and Gli2. Together, these findings suggest a novel miR-326-negative feedback loop in regulating the activity of Shh signaling.