Cyclic AMP Mediation of Epithelial Cell Function

环 AMP 介导上皮细胞功能

• 批准号: 7752546
• 负责人: JAMES Richard GOLDENRING
• 金额: $ 36.47万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-04-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7752546
• 关键词: A kinase anchoring protein; AKAP9 gene; Attention; Calmodulin; Cell membrane; Cell physiology; Cells; Centrosome; Code; Complex; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Cytoplasmic Granules; Cytosol; Epithelial Cells; Genes; Golgi Apparatus; Investigation; Location; Mediation; Membrane; Messenger RNA; Microtubules; Movement; Multiprotein Complexes; Organelles; PDE4D3; Phosphoric Monoester Hydrolases; Process; Production; Protein Kinase; Protein Kinase C; Protein phosphatase; Proteins; RNA; RNA Interference; RNA Splicing; Regulation; Role; Scaffolding Protein; Second Messenger Systems; Signal Transduction; Small Interfering RNA; Specificity; Stress; Structure; Surface; System; TRIP10 gene; Transcript; Translations; Variant; casein kinase I; novel; phosphodiesterase 4D; phosphoric diester hydrolase; public health relevance; response; scaffold; second messenger; trafficking

DESCRIPTION (provided by applicant): Subcellular sequestration of second messenger-dependent mechanisms provides for specificity of signaling to discrete organelle systems or, in the case of polarized epithelial cells, plasma membrane domains. Multiprotein scaffolds coordinate cell-specific and intracellular location-specific signaling mechanisms. A kinase anchoring proteins (AKAPs) compromise the largest group of multifunctional scaffolding proteins, which anchor not only Type II cAMP- dependent protein kinase (PKA), but also a variety of protein kinases, phosphatases, phosphodiesterases and targets of second messenger regulated signaling. The AKAP350/450 gene codes for a number of different splice variants ranging from 250 to 450 kDa. AKAP350/450 splice variants potentially scaffold PKA, protein kinase C?, PKN, casein kinase 1, phosphodiesterase 4D3, protein phosphatases 1 and 2a and calmodulin as well as a number of putative downstream effectors. AKAP350 is localized to both centrosomes and the Golgi apparatus, and we have demonstrated that depletion of AKAP350A with siRNA leads to disruption of the Golgi structure as well as alteration of polymerizing microtubules. Importantly, while previous investigations have focused attention on AKAP350 at the centrosome and the Golgi apparatus, our recent studies have led to the recognition that in most cells a large cytosolic pool of AKAP350 associates with CCAR1 and caprin and regulates mRNA trafficking and participates in microtubule-dependent stress granule formation. While we and others have demonstrated that AKAP350 can potentially scaffold a wide range of proteins, the actual composition of scaffolded complexes is likely both cell specific as well as subcellular organelle specific. The challenge of studying these large anchored multiprotein complexes is to discern the role of specific coordinated complexes in the regulation of intracellular processes. We have hypothesized that intracellular AKAP350-coordinated complexes regulate both trafficking through the Golgi apparatus and processing of discrete RNA species within cytosolic domains. To examine these hypotheses, we will pursue two specific aims. First, we will determine the role of AKAP350A and its associated proteins in regulating the structure and function of the Golgi apparatus. Second, we will investigate the role of the cytosolic pool of AKAP350A and its associated proteins in regulating RNA trafficking and translation. These studies will establish the roles of specific multiprotein complexes scaffolded by AKAP350 in localized regions of the cell. PUBLIC HEALTH RELEVANCE: AKAP350 is a large protein that can potentially assemble large regulatory compress within the cell. These complexes appear to coordinate the movement intracellular proteins and messenger RNAs responsible for far ranging processes within cells. These processes can have diverse influences on the proper functioning of cells including the production and targeting of proteins to membrane surfaces and the response of cells to various induced stresses in normal and pathological conditions.

描述（由申请人提供）：第二信使依赖性机制的亚细胞隔离提供了对离散细胞器系统的信号传导特异性，或者在极化上皮细胞的情况下，提供了对质膜结构域的信号传导特异性。多蛋白支架协调细胞特异性和细胞内位置特异性信号传导机制。激酶锚定蛋白（AKAP）是最大的一类多功能支架蛋白，其不仅锚定II型cAMP依赖性蛋白激酶（PKA），而且锚定多种蛋白激酶、磷酸酶、磷酸二酯酶和第二信使调节信号传导的靶标。AKAP 350/450基因编码许多不同的剪接变体，范围从250至450 kDa。AKAP 350/450剪接变体可能支架PKA，蛋白激酶C？，PKN、酪蛋白激酶1、磷酸二酯酶4D 3、蛋白磷酸酶1和2a和钙调蛋白以及许多推定的下游效应物。AKAP 350定位于中心体和高尔基体，我们已经证明，AKAP 350 A与siRNA的耗尽导致破坏高尔基体结构以及改变聚合微管。重要的是，虽然以前的研究集中在AKAP 350的中心体和高尔基体，我们最近的研究已经认识到，在大多数细胞中，AKAP 350与CCAR 1和山羊蛋白相关，调节mRNA的运输，并参与微管依赖性应激颗粒的形成。虽然我们和其他人已经证明AKAP 350可以潜在地支架广泛的蛋白质，但支架复合物的实际组成可能是细胞特异性的以及亚细胞器特异性的。研究这些大的锚定多蛋白复合物的挑战是辨别特定的协调复合物在调节细胞内过程中的作用。我们假设细胞内AKAP 350协调复合物调节通过高尔基体的运输和胞质结构域内离散RNA种类的加工。为了检验这些假设，我们将追求两个具体目标。首先，我们将确定AKAP 350 A及其相关蛋白在调节高尔基体的结构和功能中的作用。其次，我们将研究AKAP 350 A及其相关蛋白在调节RNA运输和翻译中的作用。这些研究将建立AKAP 350在细胞局部区域中支架化的特异性多蛋白复合物的作用。公共卫生相关性：AKAP 350是一种大蛋白质，可能在细胞内组装大的调节压缩。这些复合物似乎协调细胞内蛋白质和信使RNA的运动，这些蛋白质和信使RNA负责细胞内的远程过程。这些过程可以对细胞的正常功能产生不同的影响，包括蛋白质的产生和靶向膜表面以及细胞对正常和病理条件下各种诱导应激的反应。