Department of Hepatobiliary Surgery, Daping Hospital, The Third Military Medical University (Army Medical University), 10# Changjiangzhilu Daping, Chongqing, 400042, China.
Dig Dis Sci. 2018 Sep;63(9):2362-2372. doi: 10.1007/s10620-018-5113-5. Epub 2018 May 17.
Transmembrane and ubiquitin-like domain-containing 1 protein (Tmub1) negatively regulates liver regeneration. However, whether this regulation involves posttranscriptional modification of Tmub1 expression is unknown.
The aim of the study was to investigate whether microRNA (miR)-27a/b regulates posttranscriptional modification of Tmub1 and cell proliferation during liver regeneration.
Tmub1 mRNA 3'-untranslated region (UTR) sequences were analyzed using online software. A luciferase assay was used to verify the relationship between miR-27a/b and the 3'-UTR of Tmub1. Rat partial hepatectomy models were used to investigate miR-27a/b and Tmub1 levels after partial hepatectomy. MiR-27a/b expression was down- and up-regulated with mimics and inhibitors, respectively, to observe the effects of miR-27a/b on Tmub1 expression. Quantitative RT-PCR and Western blot analyses were used to measure miR-27a/b and Tmub1 expression. Hepatocyte proliferation was measured using the CCK8 method for BRL-3A liver cells and proliferating cell nuclear antigen and histone H3 phosphorylation in the regenerating liver.
A potential binding site of miR-27a/b was found in the 3'-UTR sequence of Tmub1. Our luciferase assay confirmed that the Tmub1 mRNA 3'-UTR was the target of miR-27a/b. We observed a temporal correlation between miR-27a/b and Tmub1 expression during liver regeneration. MiR-27a/b down-regulated Tmub1 expression both in vivo and in vitro. MiR-27a/b regulated hepatocyte proliferation during liver regeneration.
MiR-27a/b regulates hepatocyte proliferation by controlling posttranscriptional modification of Tmub1 during liver regeneration.
跨膜和泛素样结构域蛋白 1（Tmub1）负调控肝再生。然而，这种调控是否涉及 Tmub1 表达的转录后修饰尚不清楚。
本研究旨在探讨 microRNA（miR）-27a/b 是否调节肝再生过程中 Tmub1 的转录后修饰和细胞增殖。
使用在线软件分析 Tmub1 mRNA 3'非翻译区（UTR）序列。使用荧光素酶报告基因实验验证 miR-27a/b 与 Tmub1 3'UTR 的关系。采用大鼠部分肝切除术模型，研究部分肝切除术后 miR-27a/b 和 Tmub1 水平。用 mimics 和抑制剂分别下调和上调 miR-27a/b 的表达，观察 miR-27a/b 对 Tmub1 表达的影响。采用定量 RT-PCR 和 Western blot 分析检测 miR-27a/b 和 Tmub1 的表达。采用 CCK8 法检测 BRL-3A 肝细胞中 miR-27a/b 和 Tmub1 的表达，检测再生肝中增殖细胞核抗原和组蛋白 H3 的磷酸化。
在 Tmub1 的 3'UTR 序列中发现了 miR-27a/b 的潜在结合位点。我们的荧光素酶报告基因实验证实 Tmub1 mRNA 3'UTR 是 miR-27a/b 的靶标。我们观察到 miR-27a/b 与肝再生过程中 Tmub1 表达之间存在时间相关性。miR-27a/b 下调体内和体外的 Tmub1 表达。miR-27a/b 调节肝再生过程中的肝细胞增殖。
miR-27a/b 通过控制肝再生过程中 Tmub1 的转录后修饰来调节肝细胞增殖。
