Kim Kun-Yong, Shin Sun Mi, Kim Jae Kwang, Paik Sang Gi, Yang Young, Choi Inpyo
Laboratory of Immunology, Korea Research Institute of Bioscience and Biotechnology, Yusong, Taejon 305-333, Republic of Korea.
Biochem Biophys Res Commun. 2004 Mar 5;315(2):369-75. doi: 10.1016/j.bbrc.2004.01.047.
The vitamin D3 up-regulated protein 1 (VDUP1) is identified as interacting protein with thioredoxin (TRX) and functions as a natural antagonist of TRX. Its expression is regulated by various stresses including ROS, UV, and heat shock. In the present study, we observed an inducible expression of VDUP1 in Bosc cells by high density and serum deprivation cultures. To determine transcription factors associated with the induction of VDUP1 by stresses, the promoter region of VDUP1 was cloned. Through reporter assays with plasmids having various deletion of its promoter region and analysis of putative cis-elements, heat shock factor element (HSE) was identified. The deletion of HSE abolished transcriptional activity of VDUP1 promoter by stresses and the binding of heat shock factor (HSF) to HSE was confirmed by gel-shift and supershift assays using nuclear extracts prepared from stressed Bosc cells. Also, the enforced expression of HSF or heat shock increased the transcription of endogenous VDUP1. These imply that HSF is an important transcription factor involved in up-regulation of VDUP1 expression by stresses such as high density and serum deprivation cultures.
维生素D3上调蛋白1（VDUP1）被鉴定为与硫氧还蛋白（TRX）相互作用的蛋白，并作为TRX的天然拮抗剂发挥作用。其表达受包括活性氧（ROS）、紫外线和热休克在内的各种应激调节。在本研究中，我们观察到在高密度和血清剥夺培养条件下，Bosc细胞中VDUP1的诱导表达。为了确定与应激诱导VDUP1相关的转录因子，克隆了VDUP1的启动子区域。通过对具有其启动子区域各种缺失的质粒进行报告基因分析以及对假定的顺式元件进行分析，鉴定出热休克因子元件（HSE）。HSE的缺失消除了应激对VDUP1启动子的转录活性，并且通过使用从应激的Bosc细胞制备的核提取物进行凝胶迁移和超迁移分析，证实了热休克因子（HSF）与HSE的结合。此外，HSF的强制表达或热休克增加了内源性VDUP1的转录。这些表明HSF是参与通过高密度和血清剥夺培养等应激上调VDUP1表达的重要转录因子。
