ROLE OF CYTOPLASMIC P27KIP1 IN CELL MOTILITY AND METASTASIS

细胞质 P27KIP1 在细胞运动和转移中的作用

• 批准号: 7420770
• 负责人: STEVEN F DOWDY
• 金额: $ 0.29万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-20 至 2007-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7420770
• 关键词: actins; cell cycle proteins; cell motility; cytoplasm; enzyme inhibitors; metastasis; neoplasm /cancer; protein kinase; role

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. Metastasic tumor growth is the principal event leading to death in patients with cancer, however, its molecular basis is presently poorly understood. Metastasic tumor cells generally migrate at a faster rate than normal cells or non-metastasic tumor cells. This observation leads to the hypothesis that increased cell motility (migration) is necessary for cells to become metastasic. Recently, a novel cytosolic-dependent role for the cyclin:CDK inhibitor p27KIP1 in cell motility was identified. It was shown that HGF signaling via the Met receptor resulted in the nuclear export of p27 KIP1 into the cytoplasm. This cytosolic localization was required for p27 KIP1 to induce cell motility and resulted in actin cytoskeletal rearrangements. These results suggest that deregulated signaling in tumor cells induce cytoplasmic import of p27. Our central hypothesis is that in the cytoplasm, p27 assembles into a complex involved in cytoskeletal remodeling and cell migration resulting in increased metastasis. The cytoplasmic relocalization and involvement of p27 in actin cytoskeletal rearrangement are evolutionarily reminiscent of alpha factor pheromone signaling in yeast. Far1p, the yeast cyclin:cdk inhibitor, mediates both a G1 cell cycle arrest in the nucleus and induction of shmoo formation in the cytoplasm that orients the actin cytoskeleton toward the opposite mating partner . In response to alpha factor, Far1p translocates from the nucleus to the cytoplasm and interacts with Cdc24p, a guanine nucleotide exchange factor for Cdc42p. Consistent with this functional analogy, mutation of a Far1p-like sequence motif present in the p27 scatter domain inactivates both cell migration and actin rearrangement, but preserves the cell cycle arrest functions of p27. Our objective is to identify the proteins complexes binding to p27 in the cytoplasm by TAP-tag purification and mass spectrometry analysis.

该子项目是利用 NIH/NCRR 资助的中心拨款提供的资源的众多研究子项目之一。子项目和研究者 (PI) 可能已从另一个 NIH 来源获得主要资金，因此可以在其他 CRISP 条目中出现。列出的机构是中心的机构，不一定是研究者的机构。转移性肿瘤生长是导致癌症患者死亡的主要事件，然而，目前对其分子基础知之甚少。转移性肿瘤细胞通常比正常细胞或非转移性肿瘤细胞以更快的速度迁移。这一观察结果得出这样的假设：增加细胞运动（迁移）对于细胞转移是必要的。最近，细胞周期蛋白：CDK 抑制剂 p27KIP1 在细胞运动中的一种新的细胞质依赖性作用被确定。结果表明，通过 Met 受体的 HGF 信号传导导致 p27 KIP1 向细胞质中的核输出。 p27 KIP1 需要这种胞质定位来诱导细胞运动并导致肌动蛋白细胞骨架重排。这些结果表明，肿瘤细胞中信号传导失调会诱导 p27 进入细胞质。我们的中心假设是，在细胞质中，p27 组装成参与细胞骨架重塑和细胞迁移的复合物，从而导致转移增加。 p27 在肌动蛋白细胞骨架重排中的细胞质重新定位和参与在进化上让人想起酵母中的 α 因子信息素信号传导。 Far1p 是酵母细胞周期蛋白：cdk 抑制剂，介导细胞核中的 G1 细胞周期停滞和细胞质中 shmoo 形成的诱导，从而将肌动蛋白细胞骨架定向到相反的交配伙伴。响应 α 因子，Far1p 从细胞核易位到细胞质，并与 Cdc24p（Cdc42p 的鸟嘌呤核苷酸交换因子）相互作用。与这种功能类比一致，p27 分散域中存在的 Far1p 样序列基序的突变使细胞迁移和肌动蛋白重排失活，但保留了 p27 的细胞周期阻滞功能。我们的目标是通过 TAP 标签纯化和质谱分析来鉴定与细胞质中 p27 结合的蛋白质复合物。