DARTMOUTH COL COBRE: P2: REGULATION OF ENDOCYTIC TRAFFICKING OF CFTR

达特茅斯 COL COBRE：P2：CFTR 内吞贩运的监管

• 批准号: 7382074
• 负责人: Agnieszka Swiatecka-Urban
• 金额: $ 23.18万
• 依托单位: DARTMOUTH COLLEGE
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-07-01 至 2007-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7382074
• 关键词: DARTMOUTH; COL; COBRE; P2; REGULATION

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Our long-term goal is to elucidate the endocytic trafficking pathway of the cystic fibrosis transmembrane conductance regulator (CFTR) in order to develop a strategy to correct defective endocytic trafficking of deltaF508-CFTR in individuals with Cystic Fibrosis (CF). DeltaF508, the most common mutation in CF causes: (1) retention of CFTR in the endoplasmic reticulum (ER), (2) reduced open probability of the CFTR CI channel, and (3) decreased plasma membrane half-life of CFTR. Thus, correction of the defects caused by the deltaF508 mutation will require a combination therapy that includes: (1) increased exit from the ER (2) increased CI channel activity, and (3) increased plasma membrane half-life. Of these points, particularly little is known about the mechanisms that regulate the plasma membrane half-life of delta508-CFTR. The hypothesis to be tested in this proposal is that the short plasma membrane half-life of deltaF508-CFTR compared to wt-CFTR results from altered regulation of endocytic trafficking of deltaF508-CFTR. To test this hypothesis we propose three specific aims: Specific Aim #1. Test the hypothesis that the short plasma membrane half-life of deltaF508-CFTR compared to wt-CFTR results from altered endocytic trafficking of deltaF508-CFTR. The goal of this specific aim is to determine whether the decreased plasma membrane half-life of deltaF508-CFTR is caused by accelerated endocytosis or attenuated endocytic recycling of CFTR. Specific Aim #2. Test the hypothesis that Rab5a and Rab4 regulate endocytic trafficking of CFTR. The goals of this specific aim are to determine whether these proteins regulate the endocytic trafficking of CFTR and whether altered expression of Rab5a and Rab4 is responsible for the short plasma membrane half-life of deltaF508-CFTR. Specific Aim #3. To characterize the interactions between Rab5a and Rab4 with CFTR. The goals of this specific aim are to determine if Rab5a and or Rab4 interact directly with CFTR, whether the deltaF508 mutation alters the binding affinities between the Rab5a and Rab4 and CFTR, and to identify the Rab5a and Rab4 interacting proteins that may regulate the endocytic trafficking of CFTR. We anticipate that these studies will elucidate the cellular mechanisms that control the plasma membrane half-life of deltaF508-CFTR. Furthermore, we anticipate that understanding these mechanisms will lead to novel therapeutic strategies for CF and other common diseases that, similar to CF, result from abnormal regulation of protein trafficking.

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子弹和调查员（PI）可能已经从其他NIH来源获得了主要资金，因此可以在其他清晰的条目中代表。列出的机构适用于该中心，这不一定是调查员的机构。我们的长期目标是阐明囊性纤维化跨膜电导调节剂（CFTR）的内吞运输途径，以制定一种策略以纠正囊性纤维化（CF）个体中Deltaf508-CFTR的有缺陷的内吞运输。 Deltaf508是CF原因最常见的突变：（1）CFTR在内质网（ER）中保留，（2）（2）CFTR CI通道的开放概率降低，（3）降低了CFTR的质膜膜半寿命。因此，校正由Deltaf508突变引起的缺陷将需要进行组合疗法，其中包括：（1）ER（2）增加CI通道活性的增加，以及（3）质膜半衰期增加。这些点，尤其是关于调节delta508-cftr的质膜半衰期的机制知之甚少。在该提案中要检验的假设是，与WT-CFTR相比，Deltaf508-CFTR的短质膜半衰期与WT-CFTR相比，导致了Deltaf508-CFTR的内吞运输调节的改变。为了检验这一假设，我们提出了三个特定目的：特定目的＃1。检验以下假设：Deltaf508-CFTR的短质膜半衰期与WT-CFTR相比是由Deltaf508-CFTR的内吞运输变化而产生的。该特定目的的目的是确定Deltaf508-CFTR的质膜半衰期降低是由加速内吞作用或CFTR的内吞回收降低引起的。特定目标＃2。检验Rab5a和Rab4调节CFTR的内吞运输的假设。该特定目的的目标是确定这些蛋白质是否调节CFTR的内吞运输，以及Rab5a和Rab4的表达改变是否负责Deltaf508-CFTR的短质膜半寿命。特定目标＃3。表征Rab5a和Rab4与CFTR之间的相互作用。该特定目的的目标是确定Rab5a和Rab4是否与CFTR直接相互作用，Deltaf508突变是否会改变Rab5a和Rab4和CFTR之间的结合亲和力，并识别Rab5a和Rab4相互作用的蛋白质，这些蛋白可能会调节CFTR的内核运输。我们预计这些研究将阐明控制Deltaf508-CFTR的质膜半衰期的细胞机制。此外，我们预计理解这些机制将导致CF和其他常见疾病的新型治疗策略，这些疾病与CF相似，这些疾病是由于蛋白质运输的异常调节而导致的。