GOLPH3 in vascular smooth muscle cell biology and vascular disease

 描述（由申请人提供）：高尔基体（也称为高尔基复合体或高尔基体）是一种重要的细胞质细胞器，由于其在脂质和蛋白质的生物合成、运输和分选中的关键作用而引起所有科学家的极大兴趣。由于这些重要作用，其蛋白质组的任何变化都会对其功能产生负面影响，进而导致许多疾病。高尔基体磷蛋白3（Golgi phosphoprotein 3，GOLPH 3）是一种高度保守的34-kDa蛋白质，最初于2000年通过高尔基体的蛋白质组学特征鉴定，其位于高尔基体膜以及细胞溶质池中。GOLPH 3在许多肿瘤中具有很强的生物学功能，因此成为近5年来的研究热点。虽然GOLPH 3是真核细胞中的关键分子，并且在许多癌症的发病机制中，但尚未进行研究以确定其在心血管细胞生物学和心血管疾病中的作用。该提案的目标是确定GOLPH 3在血管平滑肌细胞（VSMC）生物学和增殖性血管疾病中的生物学作用。我们的初步研究首次发现GOLPH 3在VSMCs和血管壁中高度表达，并且其表达在增殖的VSMCs、球囊损伤的大鼠颈动脉、 动脉粥样硬化的小鼠动脉和动脉粥样硬化的人动脉。此外，GOLPH 3对VSMC增殖具有强作用。基于我们的初步数据，我们假设Lin-28/Let-7 d星星轴参与了增殖性VSMC和增殖性血管疾病血管壁中GOLPH 3的上调。GOLPH 3是VSMC细胞功能中的关键新分子，并且通过其下游信号通路Akt/mTOR在血管新生内膜生长和动脉粥样硬化的发展中起作用。我们的假设得到了初步数据的支持。我们将通过以下3个具体目的进一步验证这一新的假设：具体目的1是检测GOLPH 3对体外培养的VSMCs的去分化、增殖、迁移和凋亡的影响;具体目的2是确定GOLPH 3对VSMCs的细胞功能、血管损伤诱导的急性血管新生内膜生长和慢性动脉粥样硬化的影响;具体目标3是确定负责GOLPH 3介导的对VSMC的细胞效应和对增殖性血管疾病的血管效应的体外和体内的分子机制。本研究通过分析以高尔基体蛋白GOLPH 3为中心的一条新的动脉粥样硬化信号通路Lin-28/Let-7 d星星/GOLPH 3/Akt/mTOR，为动脉粥样硬化的分子机制提供新的理论依据。GOLPH 3可能是动脉粥样硬化性血管疾病的一个新的治疗靶点。

 DESCRIPTION (provided by applicant): The Golgi apparatus (also known as the Golgi complex or Golgi body) is an important cytoplasmic organelle that is of great interest to all scientists for its key roles in the biosynthesis, transporting and sorting of both lipids and proteins. As a consequence of these important roles, any changes in its proteome can negatively affect its functions and in turn lead to many diseases. Golgi phosphoprotein 3 (GOLPH3) is a highly conserved 34-kDa protein initially identified in 2000 through proteomic characterizations of the Golgi apparatus, which is located at the Golgi membrane as well as in the cytosolic pool. In the past 5 years, GOLPH3 has become a hot research area, because its strong biological functions are identified in many cancers. Although GOLPH3 is a critical molecule in eukaryotic cells and in the pathogenesis of many cancers, no studies have been performed to determine its roles in cardiovascular cell biology and cardiovascular disease. The goal of this proposal is to determine the biological roles of GOLPH3 in vascular smooth muscle cell (VSMC) biology and in proliferative vascular disease. Our preliminary studies have identified for the first time that GOLPH3 is highly expressed in VSMCs and vascular walls, and its expression is significantly increased in proliferative VSMCs, balloon-injured rat carotid arteries, atherosclerotic mouse aortas and atherosclerotic human arteries. In addition, GOLPH3 has a strong effect on VSMC proliferation. Based on our preliminary data, we hypothesized that the Lin-28/Let-7d star axis is involved in the up-regulation of GOLPH3 in proliferative VSMCs and in vascular walls with proliferative vascular disease. GOLPH3 is a critical novel molecule in VSMC cellular functions and in the development of vascular neointimal growth and atherosclerosis via its downstream signaling pathway, Akt/mTOR. Our hypothesis is supported by our preliminary data. We will further test this novel hypothesis by the following 3 Specific Aims: Specific Aim 1 i to test the effects of GOLPH3 on the dedifferentiation, proliferation, migration and apoptosis of cultured VSMCs in vitro; Specific Aim 2 is to determine the effects of GOLPH3 on cellular functions of VSMCs, acute vascular neointima growth induced by vascular injury, and chronic atherosclerosis in vivo; and Specific Aim 3 is to determine the molecular mechanisms responsible for GOLPH3-mediated cellular effects on VSMCs and vascular effects on proliferative vascular disease both in vitro and in vivo. The study will provide a new molecular mechanism of atherosclerosis by analysis a novel atherosclerosis signaling pathway Lin-28/Let-7d star/GOLPH3/Akt/mTOR, which is centralized by the abundant Golgi protein, GOLPH3. GOLPH3 may be a novel therapeutic target for atherosclerotic vascular disease.