Centrosomes and BRCA1

中心体和 BRCA1

• 批准号: 7216300
• 负责人: JEFFREY D PARVIN
• 金额: $ 0.93万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-04-01 至 2007-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7216300
• 关键词: BRCA1 Protein; BRCA1 gene; Biological; Biological Assay; Breast; Cell Line; Cells; Centrosome; Chimeric Proteins; DNA; Data; Epithelial Cells; Epithelium; Etiology; Event; Growth; In Vitro; Laboratories; Learning; Lesion; Lysine; Malignant neoplasm of ovary; Mammary Gland Parenchyma; Mammary gland; Mass Spectrum Analysis; Microtubules; Modification; Mutation; Normal Cell; Numbers; Organelles; Pan Genus; Pathway interactions; Phenotype; Process; Protein Binding; Protein Inhibition; Proteins; Publishing; Regulation; Research; Research Personnel; Small Interfering RNA; Testing; Tubulin; Tumor Suppressor Proteins; Ubiquitination; Work; cell type; in vitro Assay; in vivo; malignant breast neoplasm; mutant; osteosarcoma; polypeptide; programs; research study; tissue culture; tumor; ubiquitin ligase; ubiquitin-protein ligase

DESCRIPTION (provided by applicant): Why mutations in the BRCA1 gene result in breast and ovarian cancer is unknown. Recent data from this laboratory suggest that the ubiquitination activity of the BRCA1 tumor suppressor regulates the duplication and function of centrosomes specifically in mammary epithelial cells in tissue culture. Using a transient assay to inhibit BRCA1 function, we have not observed centrosome amplification in cell lines derived from non- breast tissue. Centrosome amplification has been observed in the earliest and most aggressive breast cancer lesions, and it is likely that this function of BRCA1 is critical in the etiology of these tumors. Our data has revealed a new biological pathway, which controls centrosome number and function and which depends on the function of BRCA1 in breast cells. This project will dissect the BRCA1 function via three aims. 1.) Polypeptide targets of BRCA1 ubiquitination will be identified from centrosomes purified from breast cell lines. Proteins modified by the BRCA1-dependent ubiquitination activity will be assayed for effects on centrosome duplication. 2.) The effects of BRCA1-dependent ubiquitination on centrosome microtubule nucleation function will be assayed in vitro and in vivo, and the proteins and ubiquitinated substrates identified in aim 1 will also be tested for modulating the function of BRCA1 on this organelle. 3.) We will identify the factors in non-breast cells which render the BRCA1 ubiquitination activity redundant, and test whether the newly identified factor plus BRCA1 regulate centrosome amplification in these cell types. This project will identify the mechanism by which BRCA1 regulates centrosome duplication and centrosome function in breast cells. One of the earliest changes in the cells in an incipient breast cancer is a problem with the cellular machine that segregates the DNA when the breast cell divides. Research in this laboratory has found that the function of this machine, called a centrosome, is controlled in breast cells by the BRCA1 protein. This project will dissect the workings of the centrosome and determine how BRCA1 controls its function in normal cells, and we will learn how this process is changed when BRCA1 function is lost by mutation as happens in breast cancer.

描述（由申请人提供）：为什么BRCA1基因中的突变导致乳腺癌和卵巢癌尚不清楚。该实验室的最新数据表明，BRCA1肿瘤抑制剂的泛素化活性调节了在组织培养中专门在乳腺上皮细胞中的中心体的重复和功能。使用瞬态测定来抑制BRCA1功能，我们尚未观察到来自非乳腺组织的细胞系中的中心体扩增。在最早，最侵略性的乳腺癌病变中观察到了中心体扩增，并且BRCA1的这种功能在这些肿瘤的病因学中很可能至关重要。我们的数据揭示了一种新的生物途径，该途径控制着中心体的数量和功能，并取决于BRCA1在乳腺细胞中的功能。该项目将通过三个目标解剖BRCA1功能。 1.）将从乳腺细胞系纯化的中心体中鉴定出BRCA1泛素化的多肽靶标。通过依赖BRCA1依赖性泛素化活性修饰的蛋白质将分析对中心体重复的影响。 2.）将在体外和体内分析BRCA1依赖性泛素化对中心体微管成核功能的影响，并且在AIM 1中鉴定的蛋白质和泛素化底物也将进行测试，以调节该细胞器上BRCA1的功能。 3.）我们将确定呈现BRCA1泛素化活性冗余的非胸细胞中的因素，并测试新鉴定的因子加上BRCA1是否调节这些细胞类型中的中心体扩增。该项目将确定BRCA1调节乳腺细胞中心体重复和中心体功能的机制。初期乳腺癌中细胞中最早的变化之一是细胞机的问题，当乳腺细胞分裂时将DNA分离。该实验室的研究发现，该机器的功能（称为中心体）通过BRCA1蛋白在乳腺细胞中控制。该项目将剖析中心体的起作用，并确定BRCA1如何控制其在正常细胞中的功能，我们将在BRCA1函数因突变丢失时如何改变该过程，就像乳腺癌中发生的那样。