Validation of rTS as a Molecular Target

rTS 作为分子靶标的验证

• 批准号: 6515047
• 负责人: BRUCE JEFFREY DOLNICK
• 金额: $ 16.72万
• 依托单位: ROSWELL PARK CANCER INSTITUTE CORP
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-03-01 至 2004-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6515047
• 关键词: RNA; antisense nucleic acid; cell line; chemical structure function; colon neoplasms; combinatorial chemistry; enzyme activity; enzyme induction /repression; fatty acids; high throughput technology; isomerase; lactones; methionine; neoplasm /cancer genetics; nuclear magnetic resonance spectroscopy; reporter genes; thymidylate synthase

Our laboratory has discovered, cloned and sequenced the rTS gene. The rTS gene overlaps the TS (thymidylate synthase) gene and codes for a naturally occurring antisense RNA (rTSa mRNA) and two proteins (rTSalpha and rTSP). It is proposed that the rTS proteins are involved in the synthesis of signal molecules that modulate cell growth through a mechanism similar to quorum sensing functions in bacteria. The rTS proteins have homology to RspA, a bacterial protein that can interfere with quorum sensing. Expression of the rTS gene is linked to slowed growth of cells and diminished TS levels as a function of cell population density. Human colon tumor cells (H630-1) that overproduce rTS secrete a molecule that can down-regulate TS in other cells without cell-to-cell contact, suggesting rTS mediates synthesis of a signal molecule. These same cells secrete a molecule that can effect a quorum sensing response in a bacteria-based bioassay. Analogs (acyl homocysteine thiolactones, AHTs) of the molecules hypothesized to be synthesized by rTS proteins) have been chemically prepared and been found to alternatively stimulate and inhibit growth and colony formation of cultured human colon tumor cells. In patient materials we have found that expression of rTSbeta protein is down regulated in a significant number (5/14) of colon tumors compared to paired normal mucosa, suggesting the growth inhibitory function is selected against by tumors in vivo. We propose to evaluate the rTS gene products as targets for drug development. To validate rTS as a possible chemotherapeutic target we propose two Specific Aims: 1) Develop a high-throughput assay to identify compounds that activate rTS function; 2) Synthesize and evaluate a variety of potential rTS ligands to validate rTS as a potential chemotherapeutic target.

我们的实验室发现，克隆并测序了RTS基因。 RTS基因与TS（胸苷酸合酶）基因重叠，并编码天然存在的反义RNA（RTSA mRNA）和两种蛋白质（RTSALPHA和RTSP）。有人提出，RTS蛋白参与信号分子的合成，该信号分子通过类似于细菌的法规传感功能的机制调节细胞生长。 RTS蛋白与RSPA具有同源性，RSPA是一种细菌蛋白，可以干扰法定人数。 RTS基因的表达与细胞的生长缓慢有关，而TS水平降低，与细胞种群密度的关系降低。人类结肠肿瘤细胞（H630-1）过量生产RTS分泌一个可以在没有细胞对细胞接触的其他细胞中下调TS的分子，这表明RTS介导了信号分子的合成。这些相同的细胞分泌一个可以在基于细菌的生物测定中影响法定感应反应的分子。已化学制备了假设是由RTS蛋白合成的分子的类似物（酰基同型半胱氨酸硫代酮，Ahts），并被发现可以替代刺激和抑制培养的人类结肠肿瘤细胞的生长和菌落形成。在患者材料中，我们发现与配对的正常粘膜相比，RTSBETA蛋白的表达在大量（5/14）的结肠肿瘤（5/14）中受到下降，这表明在体内肿瘤对肿瘤选择了生长抑制功能。我们建议评估RTS基因产品作为药物开发的靶标。为了验证RT作为可能的化学治疗靶标，我们提出了两个具体目的：1）开发高通量测定法以识别激活RTS功能的化合物； 2）合成并评估各种潜在的RTS配体以验证RTS作为潜在的化学治疗靶标。