The expression of Argonaute2 and related microRNA biogenesis proteins in normal and hypoxic trophoblasts
The expression of Argonaute2 and related microRNA biogenesis proteins in normal and hypoxic trophoblasts
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DOI：
10.1093/molehr/gam006
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发表时间：
2007-04-01
影响因子：
4
通讯作者：
Sadovsky, Yoel
中科院分区：
文献类型：
--
作者：
Donker, Rogier B.;Mouillet, Jean-Francois;Sadovsky, Yoel
内源性microRNAs（miRNAs）在组织发育和功能过程中转录后调节mRNA和蛋白质表达。尽管对环境损伤的适应在人体组织中受到严格调控，但miRNA和miRNA生物发生蛋白在此背景下的作用尚未充分探索。我们试图分析关键RNAi酶Argonaute 2（Ago 2）和其他miRNA生物合成蛋白在人滋养层细胞分化过程中和缺氧环境中的表达。使用对初级人类滋养层细胞的体外分析，我们鉴定了核心miRNA生物发生蛋白在人类绒毛滋养层细胞中的表达，其表达水平不受细胞分化的影响。我们发现，miRNA生物合成途径是功能性的，并产生miRNA，在低氧环境中，miR-93上调，miR-424下调。与此相反，缺氧并没有改变关键的miRNA机器蛋白的表达。关键的miRNA加工酶Ago 2，沿着其相互作用蛋白DP 103，在正常胎盘以及胎盘灌注不足导致胎儿生长受限的妊娠胎盘中表达。Ago 2和DP 103共免疫沉淀，并没有限制滋养层对缺氧应激的反应。我们的结论是，核心miRNA机器蛋白在人类滋养层细胞中表达和功能。缺氧对胎盘miRNA种类的一个子集的表达的影响不太可能反映关键miRNA生物发生蛋白的表达改变。
Endogenous microRNAs (miRNAs) post-transcriptionally regulate mRNA and protein expression during tissue development and function. Whereas adaptation to environmental insults are tightly regulated in human tissues, the role of miRNAs and miRNA biogenesis proteins in this context is inadequately explored. We sought to analyse the expression of the key RNAi enzyme Argonaute2 (Ago2) and other miRNA biogenesis proteins in human trophoblasts during differentiation and in hypoxic environment. Using an in vitro analysis of primary term human trophoblasts, we identified the expression of the core miRNA biogenesis proteins in human villous trophoblasts, with expression levels unaffected by cellular differentiation. We found that the miRNA biosynthetic pathway was functional and produced miRNAs, with miR-93 up-regulated and miR-424 down-regulated in hypoxic environment. In contrast, hypoxia did not alter the expression of key miRNA machinery proteins. The pivotal miRNA processing enzyme Ago2, along with its interacting protein DP103, were expressed in normal placentas as well as in placentas from pregnancies complicated by placental hypoperfusion that resulted in fetal growth restriction. Ago2 and DP103 co-immunoprecipitated, and did not limit trophoblast response to hypoxic stress. We concluded that the core miRNA machinery proteins are expressed and functional in human trophoblasts. The influence of hypoxia on the expression of a subset of placental miRNA species is unlikely to reflect altered expression of key miRNA biogenesis proteins.