RETINOIDS, M6P/IGF II RECEPTOR & CELL GROWTH REGULATION

维甲酸和甘露糖6-磷酸/胰岛素样生长 因子-II(M6P/IGF2)受体已被证明在 在发育和肿瘤发生中控制细胞生长的作用。 最近的工作发现，维甲酸(RA)与M6P/IGF2结合 高亲和力的受体，导致原发灶的改变 受体的功能和抑制细胞生长。这些 结果提示M6P/IGF2受体介导一种新的RA反应 可能在细胞生长调节中起重要作用的途径。然而， 这一途径背后的分子机制在很大程度上仍不清楚。 因此，本提案的总体目标是了解RA如何 与M6P/IGF2受体相互作用及其作用 在细胞生长调节方面。我们希望解决的关键问题 是：1)受体蛋白的功能区在哪里 负责维甲酸的结合？2)什么是真正的生物学 这种互动的后果是什么？以及3)它们是如何工作的？因此， 本申请的具体目的是：(1)鉴定维甲酸 M6P/IGF2受体的结合部位；(2)扩大认识 RA-M6P/IGF2R相互作用的生物学后果。(3)至 确定对生物过程负责的生化过程 RA-M6P/IGF2R相互作用的影响我们的总体方法是创建 M6P/IGF2R突变体未能与RA结合，然后评估 表达野生型的细胞对RA的功能反应 M6P/IGF2R和具有突变受体的基因。实现以下目标的主要方法 用于蛋白质诱变、光亲和标记、氨基酸 序列分析、配基结合分析、免疫检测、酶促 测定和形态分析。 意义此项目将提供有关以下方面的基本信息 维甲酸如何与M6P/IGF2受体相互作用并阐明 这一新的类维甲酸反应通路在细胞调控中的作用 成长。这种知识可能会导致新的或更有效的治疗方法 以及癌症和发育缺陷的预防方法。

Both retinoids and the mannose 6-phosphate/insulin-like growth factor-II (M6P/IGF2) receptor have been shown to play fundamental roles in the control of cell growth in development and oncogenesis. Recent work has discovered that retinoic acid (RA) binds to the M6P/IGF2 receptor with high affinity, leading to alteration of the primary functions of the receptor and suppression of cell growth. These findings suggest that M6P/IGF2 receptor mediates a novel RA response pathway that may be important in cell growth regulation. However, the molecular mechanism underlying this pathway remains largely unknown. Thus, the overall goal of this proposal is to understand how RA interacts with the M6P/IGF2 receptor and the role of this interaction in cell growth regulation. The key questions that we wish to address are: 1) Where is the functional domain of the receptor protein responsible for retinoid binding? 2) What is the authentic biological consequence of the interaction? and 3) How do they work? Accordingly, the specific aims of this application are: (1) To identify the retinoid binding site of the M6P/IGF2 receptor; (2) To extend the understanding of the biological consequence of the RA-M6P/IGF2R interaction. (3) To identify the biochemical processes responsible for the biological effect of RA-M6P/IGF2R interaction. Our general approach is to create a mutant M6P/IGF2R that fails to bind RA and then assess differences of functional responses to RA between the cells expressing wild-type M6P/IGF2R and those with the mutant receptor. The principal methods to be used include protein mutagenesis, photoaffinity labeling, amino acid sequence analysis, ligand binding assay, immuno-detection, enzymatic assay and morphological analysis. Significance This project will provide fundamental information about how retinoids interact with the M6P/IGF2 receptor and shed light on the role of this novel retinoid-response pathway in regulation of cell growth. This knowledge may lead to novel or more effective therapeutic and preventive approaches for cancer and developmental defects.