Phosphorylation and isomerization of nuclear orphan receptor TR3 and its regulation on Wnt signaling pathway

摘要 第一章核孤儿受体TR3概述 TR3（又被称为NGFI-B、Nur77）是一种核受体，属于类固醇/甲状腺/视黄酸受体家族成员。由于目前尚未发现TR3特异性配体，因此被称为核孤儿受体。TR3是一种立早基因，可以被许多生长因子或凋亡因子迅速诱导表达，其转录后水平的修饰则影响着TR3功能的发挥。作为转录因子，TR3通过与其应答元件NBRE或NurRE的结合，调控着许多基因的转录，从而参与对细胞增殖、凋亡、新陈代谢以及炎症反应等方面的调控。另一方面，TR3的亚细胞定位也影响着生物学功能的发挥。当TR3从细胞核转运到细胞浆并定位于线粒体后，将使Bcl-2由凋亡抑制蛋白转变为凋亡诱导蛋白，...Abstract Chapter 1． Overview of orphan receptor TR3 The immediate-early gene product TR3 (also known as Nur77 or NGFI-B) is a nuclear receptor of the steroid/thyroid/retinoid receptor superfamily. Since its physiological ligand has not been identified, TR3 is also termed as orphan receptor. The expression of TR3 can be immediately induced by many growth factors and pro-apoptotic factors. As a ...学位：理学博士院系专业：生命科学学院生物医学科学系_细胞生物学学号：2012005140314

Expression profile of voltage-gated potassium channel Kv1.3 in aorta of atherosclerosis rats

目的探讨动脉粥样硬化(AS)大鼠主动脉病变局部离子通道kV1.3的表达水平及作用。方法雄性WISTAr大鼠16只,随机分为两组:正常组(8只,予普通饮食+0.9%氯化钠溶液)和AS组(8只,予高脂饮食+维生素d3负荷)。采用组织病理学检查,观察主动脉粥样硬化病变。采用实时定量反转录-聚合酶链反应(rT-PCr)和WESTErn印迹法检测主动脉病变局部kV1.3和白细胞介素(Il)-2、干扰素(Ifn)-γ的表达水平。结果组织病理学检查证实纤维增生性AS斑块。AS组的kV1.3MrnA为(31.48±8.64)x10-3,显著高于正常组的(3.28±0.79)x10-3(P=0.012)。AS组的kV1.3、Il-2、Ifn-γ蛋白表达量分别为0.691±0.067、0.611±0.055、0.759±0.050,均显著高于正常组的0.490±0.052、0.299±0.058、0.273±0.052(P值均<0.01)。结论 kV1.3在主动脉粥样硬化病变局部的表达增高。kV1.3可能在AS的发生和发展过程中发挥着重要的作用。Objective To investigate the expression of voltage-gated potassium channel Kv1.3 in the aorta of a rat model of atherosclerosis and its role in the progress of atherosclerotic plaque formation.Methods A total of 16 male Wistar rats were randomly divided into normal control(normal diet and saline)and atherosclerosis group(high lipid diet+Vitamin D3 overload),with 8 rats in each group.In 16 weeks later,all rats were killed after weighing,and their blood samples and aorta were collected.Pathological changes of the rat aortic artery were observed with HE staining.Real time RT-PCR and Western blotting analysis were used to determine the mRNA and protein expression of Kv1.3 and the protein expressions of interleukin(IL)-2 and interfereron(IFN)-γ.Results Pathological changes showed that fiber proliferative atherosclerotic plaques were found in the aorta of atherosclerosis group,with inflammatory cells infiltrating in the local lesion.Real time RT-PCR analysis showed that the expression of Kv1.3 mRNA in the aorta was increased significantly in the atherosclerosis rats than that in the controls([31.48±8.64]×10-3 vs.[3.28±0.79]×10-3,P<0.05).Western blotting analysis showed that the protein expression of Kv1.3,IL-2 and IFN-γ in the aorta were also increased significantly in the atherosclerotic rats than that in the controls(Kv1.3[0.691±0.067] vs.[0.490±0.052],IL-2 [0.611±0.055] vs.[0.299±0.058],IFN-γ [0.759±0.050] vs.[0.273±0.052],P<0.01 n=8).Conclusion The expression of Kv1.3 potassium channels is increased in the plaques of atherosclerotic rats.Kv1.3 may play an important role in the development and progression of atherosclerosis.国家自然科学基金资助项目(30871045

The orphan nuclear receptor TR3/Nur77 regulates ER stress and induces apoptosis via interaction with TRAP gamma

Fundamental Research Funds for the Central Universities, China [2010121096]; Fujian Provincial Department of Science and Technology [2012J01148]; National Natural Science Foundation of China [31000620]; Ministry of Education, China [B06016]The orphan nuclear receptor TR3 (also known as Nur77) belongs to the steroid/thyroid/retinoid nuclear receptor superfamily and plays important roles in regulating cell proliferation, differentiation and apoptosis. No physiological ligand for TR3 has been found thus far; the determination of its binding partners is therefore important to clarify the biological functions of TR3. Here, we identified translocon-associated protein subunit gamma (TRAP gamma) as a novel TR3 binding partner using a tandem affinity purification method. This interaction between TR3 and TRAP gamma was further confirmed, and the interacting regions were mapped. The ligand-binding domain of TR3 was required for TRAP gamma binding, and the C terminus of TRAP gamma was responsible for its interaction with TR3. When stimulated with 12-O-tetradecanoylphorbol 13-acetate (TPA) or CD437, this TR3-TRAP gamma interaction not only induced Ca2+ depletion in the endoplasmic reticulum (ER) but also promoted the expression of the proapoptotic transcriptional regulator CHOP. Notably, both TR3 and TRAP gamma were required for ER stress-induced apoptosis in HepG2 cells. Overall, this study demonstrated a novel, TR3-initiated signaling pathway in which TR3 regulates ER stress and induces apoptosis of hepatoma cells through its interaction with TRAP gamma. (c) 2013 Elsevier Ltd. All rights reserved

Orphan receptor TR3 is essential for the maintenance of stem-like properties in gastric cancer cells

National Natural Science Foundation of China (NSFC) [81172283]The orphan receptor TR3 is an important regulator of cell proliferation and apoptosis. However, whether TR3 is involved in regulating the stem-like properties of cancer cells remains unknown. The present study shows that TR3 expression is increased in gastric tumorsphere cells and is positively correlated with cancer stern cell (CSC) characteristics. Knocking down TR3 leads to the suppression of its stem-like properties in both gastric cancer cells and tumorsphere cells. This process involves the decreased expression of the sternness-related genes Oct-4 and Nanog and the invasion-related gene MMP-9. We further identify Nanog as a new target for the transcription factor TR3. Together, these data demonstrate for the first time that TR3 is essential for the maintenance of stem-like properties in human gastric cancer cells and implicate TR3 as a new therapeutic target for gastric cancer. (c) 2012 Elsevier Ireland Ltd. All rights reserved