IDENTIFICATION OF RHOGAP INTERACTING PROTEINS

RHOGAP 相互作用蛋白的鉴定

• 批准号: 8171422
• 负责人: Karen F Oegema
• 金额: $ 0.24万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2011-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8171422
• 关键词: Anaphase; Binding; Caenorhabditis elegans; Cell membrane; Cells; Collaborations; Computer Retrieval of Information on Scientific Projects Database; Copying Processes; Cytokinesis; Diffuse; Failure; Family; Funding; GTP Binding; Genome; Genomic Instability; Grant; Guanosine Triphosphate; Guanosine Triphosphate Phosphohydrolases; Immunoprecipitation; Institution; Lipids; Malignant Neoplasms; Mass Spectrum Analysis; Membrane; Microtubules; Mitosis; Modeling; Monomeric GTP-Binding Proteins; Physiological; Polyploidy; Proteins; Proteomics; Research; Research Personnel; Resources; Signal Transduction; Source; Staging; United States National Institutes of Health; Work; anillin; daughter cell; physical separation; rho; rho GTPase-activating protein

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. Mitosis is an elaborate process where the duplicated genome is segregated into two daughter cells. Cytokinesis, the final step of mitosis, is the physical separation of the two daughter cells. Failure in cytokinesis can result in polyploidy and genome instability, two hallmarks found in many cancers. During cytokinesis, signaling by the anaphase spindle generates an equatorial zone of active RhoA, which in turn directs the cortical accumulation of contractile ring components. Rho family GTPases cycle between an active GTP-bound and inactive GDP-bound form. This cycle is controlled by GEFs, which promote GTP loading, and GAPs, which inactivate small GTPases by stimulating their low intrinsic GTPase activity. During cytokinesis, it has been proposed that localization of the RhoA GEF to the spindle midzone provides a means to locally activate RhoA at the cell equator. However, as RhoGTPases are anchored in the plasma membrane with a lipid moiety and are thought to freely diffuse within the membrane, previous theoretical work has suggested that a global RhoA GAP activity would be necessary to maintain a focused equatorial zone of active Rho. In C. elegans RGA-3 and RGA-4 (RGA-3/4), two highly similar RhoGAPs, were previously shown to act preferentially on RhoA and localizes to the cleavage furrow and the microtubule asters. We find that RGA-3/4 are required to restrict the accumulation of contractile ring components including anillin and the septins to the equator of the cell during early stages of cytokinesis. During cleavage furrow ingression RGA-3/4 are also important to limit the zone of anillin and the septins to a tight region at the furrow tip. Taken together our findings support a model in which a RhoGAP helps to restrict the activation of RhoA to the cell equator. RGA-3/4. To understand how RGA-3/4 activity and/or localization are regulated through mitosis we aim to identify new binding partners of RGA-3/4 using mass spectrometry after immunoprecipitation in collaboration with The Center for Physiological Proteomics.

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。子项目及 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以在其他 CRISP 条目中表示。列出的机构是 对于中心来说，它不一定是研究者的机构。 有丝分裂是一个复杂的过程，其中复制的基因组被分离成两个子细胞。细胞分裂是有丝分裂的最后一步，是两个子细胞的物理分离。胞质分裂失败会导致多倍体和基因组不稳定，这是许多癌症中发现的两个标志。在胞质分裂过程中，后期纺锤体发出的信号产生活跃 RhoA 的赤道区，这反过来又指导收缩环成分的皮质积累。 Rho 家族 GTP 酶在活性 GTP 结合型和非活性 GDP 结合型之间循环。该循环由 GEF 和 GAP 控制，GEF 促进 GTP 负载，GAP 则通过刺激小 GTP 酶的低内在 GTP 酶活性来使其失活。在胞质分裂期间，有人提出，RhoA GEF 定位于纺锤体中区提供了一种在细胞赤道局部激活 RhoA 的方法。然而，由于 RhoGTP 酶通过脂质部分锚定在质膜上，并且被认为可以在膜内自由扩散，因此之前的理论工作表明，全局 RhoA GAP 活性对于维持活性 Rho 的集中赤道区是必要的。在秀丽隐杆线虫中，RGA-3 和 RGA-4 (RGA-3/4) 这两种高度相似的 RhoGAP 先前被证明优先作用于 RhoA 并定位于卵裂沟和微管紫苑。我们发现，在胞质分裂的早期阶段，需要 RGA-3/4 来限制收缩环成分（包括苯胺和隔膜）在细胞赤道的积累。在卵裂沟进入过程中，RGA-3/4 对于将苯胺和隔膜区域限制在沟尖端的紧密区域也很重要。总而言之，我们的研究结果支持了一个模型，其中 RhoGAP 有助于限制 RhoA 的激活到细胞赤道。 RGA-3/4。为了了解 RGA-3/4 活性和/或定位是如何通过有丝分裂进行调节的，我们的目标是与生理蛋白质组学中心合作，在免疫沉淀后使用质谱法来鉴定 RGA-3/4 的新结合伴侣。