NOVEL PROBES FOR IMMUNOPHILIN MEDIATED CELL CONTROL

海洋无脊椎动物生产各种各样的天然产品， 其中靶向特定的细胞受体。 我们发现 bastadin-5是一种来自海绵Ianthella basta的大环化合物， 的ryanodine敏感的Ca 2+通道的有效激动剂 肌浆网，SR（ER 502 μ M）。FKBP 12是一种蛋白质， 与影响Ca 2+转运的ryanodine受体相关 在SR/ER中。 Bastadin-5与FKBP 12/ryanodine受体复合物结合， 刺激Ca 2+的释放。直接调节Ca 2+释放 FKBP 12的细胞内储存和FKBP 12与钙调磷酸酶的结合， TGF-β 1受体参与级联信号转导 导致细胞增殖和其他反应的事件， 分化 这些都是重要的干预目标， 肿瘤发生 Bastadin-5与人前列腺癌细胞系的结合位点和结合基序 FKBP 12/ryanodine受体复合物是未知。这个计划 建议是，1。新型钙离子通道的分离与鉴定 FKBP 12/ryanodine受体复合物的调节剂， 海洋无脊椎动物 我们将集中讨论 Ianthella basta中的另外的巴斯塔定样化合物和六种 未经鉴定的海洋无脊椎动物样本， 显示含有有效的Ca 2+调节活性。 2.确定 所有巴斯塔丁的定量构效关系（QSAR） 激活FKBP/ryanodine受体复合物的能力， 来自SR/ER制剂的Ca 2+流出。 这将为以后提供数据 开发bastadin-5与 FKBP 12/ryanodine复合物。 3.巴斯塔丁-5的全合成和 用于定位的巴斯塔丁-5光亲和标记的类似物 FKBP 12/ryanodine复合物上的bastadin-5效应位点。 4.测试 巴斯塔丁直接与FKBP 12或FKBP 12相互作用的假设 FKBP 12/ryanodine受体复合物上的效应位点， Ryanodine功能的重大（前所未有）变化- 敏感的Ca 2+通道。 5.要了解调制的方式， FKBP 12/ryanodine受体复合物通过bastadins影响细胞 使用BC 3 H1细胞系作为模型的生长和分化。

Marine invertebrates produce a diverse array of natural products some of which target specific cellular receptors. We have found that bastadin-5, a macrocycle from the marine sponge Ianthella basta is a potent agonist of the ryanodine-sensitive Ca2+ channel of the sarcoplasmic reticulum, SR (ER502muM). FKBP12 is a protein physically associated with the ryanodine receptor that affects Ca2+ transport across SR/ER. Bastadin-5 binds to FKBP12/ryanodine receptor complex and stimulates release of Ca2+. Direct modulation of Ca2+ release from intracellular stores by FKBP12 and binding of FKBP12 to calcineurin and the TGF-beta1 receptor are involved in a cascade of signal transduction events that lead to among other responses, cell proliferation and differentiation. These are important targets for intervention in tumorigenesis. The locus of binding and binding motif of bastadin-5 to the FKBP12/ryanodine receptor complex are unknown. The plan of this proposal is, 1. Isolation and characterization of new Ca2+ channel modulators of the FKBP12/ryanodine receptor complex from extracts of marine invertebrates. We will concentrate on the structures of additional bastadin-like compounds in Ianthella basta and six unidentified marine invertebrate samples which have been screened and shown to contain potent Ca2+ modulatory activity. 2. Determine the quantitative structure-activity relationships (QSAR) for all bastadins for their ability to activate the FKBP/ryanodine receptor complex and Ca2+ efflux from SR/ER preparations. This will provide data for later development of a functional model for bastadin-5 interaction with the FKBP12/ryanodine complex. 3. Total synthesis of bastadin-5 and bastadin-5 photoaffinity-labelled analogs for use in localization of the bastadin-5 effector site on FKBP12/ryanodine complex. 4. Test the hypothesis that bastadins interact directly with FKBP12 or the FKBP12 effector site on the FKBP12/ryanodine receptor complex to affect a significant (unprecedented) change in the function of ryanodine- sensitive Ca2+ channels. 5. To understand how modulation of the FKBP12/ryanodine receptor complex by bastadins influences cellular growth and differentiation using the BC3H1 cell line as model.