Defining USP22 Functions During Mammalian Development

定义哺乳动物发育过程中的 USP22 功能

• 批准号: 8825514
• 负责人: SHARON Y. R. DENT
• 金额: $ 31.64万
• 依托单位: UNIVERSITY OF TX MD ANDERSON CAN CTR
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-04-01 至 2017-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8825514
• 关键词: Acetyltransferase; Alleles; Cancerous; Catalytic Domain; Cells; Cessation of life; ChIP-seq; Chromatin; Complex; Development; Embryonic Development; Gene Activation; Gene Expression Regulation; Gene Proteins; Gene Targeting; Genes; Genetic Transcription; Genomics; Histone H2B; Histone H3; Histones; Human; Lead; Link; Location; Longitudinal Studies; LoxP-flanked allele; Maintenance; Malignant Neoplasms; Mus; Mutant Strains Mice; Oncogenic; Orthologous Gene; Peptide Hydrolases; Phenotype; Play; Polycomb; Proteins; Proteomics; Role; SAGA; Stem Cell Development; Stem cells; Testing; Time; Transcript; Ubiquitin; Work; Yeasts; aggressive therapy; cancer diagnosis; cancer stem cell; embryonic stem cell; fly; insight; loss of function; member; mouse development; mutant; pluripotency; programs; research study; therapy resistant; transcriptome sequencing; tumor; tumorigenesis; ubiquitin-specific protease

DESCRIPTION (provided by applicant): The highly conserved SAGA complex plays important roles in gene regulation in yeast, fly, mouse, and human cells. Acetyltransferase activity in SAGA is provided by Gcn5, but the complex also contains a ubiquitin specific protease activity provided by USP22 (humans and mice) or its orthologs, nonstop (flies) and Ubp8 (yeast). USP22 was identified as part of an 11 gene 'death from cancer' stem cell signature in highly metastatic, therapy-resistant human tumors, but how over expression of USP22 contributes to a cancer stem cell phenotype, or whether these functions are related to the overall functions of the SAGA complex is not yet clear. We previously created several mutant alleles of Gcn5 to probe SAGA functions during mammalian development, and our studies indicate that the SAGA complex has important HAT-independent functions during early development. At least some of these functions are likely related to USP22, since we discovered that Gcn5 deletion results in diminished USP22 activity (Atanassov et al, 2009). We hypothesize that USP22 has important functions in embryonic stem cells and in embryo development that may be directly related to its roles in tumorigenesis. Our recent studies using USP22 gene trap alleles confirm that USP22 functions are important for normal embryo development and survival. We will further define the developmental roles of USP22 through: 1) Definition of SAGA dependent and independent USP22 functions by creating mice bearing either a floxed allele or a catalytically dead allele of USP22 2) Definition of USP22 functions in mouse ES cells before and after differentiation through both loss of function and over expression approaches and 3) Determination of genomic locations, gene targets and protein substrates of USP22 in ES cells. In the long term, these studies will provide important insights into how USP22 over expression contributes to the formation or maintenance of cancer stem cells and the development of highly aggressive tumors.

描述（由申请人提供）：高度保守的SAGA复合物在酵母、果蝇、小鼠和人类细胞的基因调控中发挥着重要作用。 SAGA 中的乙酰转移酶活性由 Gcn5 提供，但该复合物还包含由 USP22（人类和小鼠）或其直向同源物、nonstop（果蝇）和 Ubp8（酵母）提供的泛素特异性蛋白酶活性。 USP22 被鉴定为高度转移、治疗耐药的人类肿瘤中 11 个基因“癌症死亡”干细胞特征的一部分，但 USP22 的过度表达如何促进癌症干细胞表型，或者这些功能是否与 SAGA 复合物的整体功能相关尚不清楚。我们之前创建了几个 Gcn5 突变等位基因来探测哺乳动物发育过程中的 SAGA 功能，我们的研究表明 SAGA 复合物在早期发育过程中具有重要的不依赖于 HAT 的功能。至少其中一些功能可能与 USP22 有关，因为我们发现 Gcn5 缺失会导致 USP22 活性减弱（Atanassov 等，2009）。我们假设 USP22 在胚胎干细胞和胚胎发育中具有重要功能，这可能与其在肿瘤发生中的作用直接相关。我们最近使用 USP22 基因陷阱等位基因进行的研究证实，USP22 功能对于正常胚胎发育和存活很重要。我们将通过以下方式进一步定义 USP22 的发育作用： 1) 通过创建携带 USP22 floxed 等位基因或催化死亡等位基因的小鼠来定义 SAGA 依赖和独立的 USP22 功能 2) 通过功能丧失和过度表达方法来定义分化前后小鼠 ES 细胞中 USP22 的功能 3) 确定 USP22 的基因组位置、基因靶标和蛋白质底物 ES细胞。从长远来看，这些研究将为了解 USP22 过度表达如何促进癌症干细胞的形成或维持以及高度侵袭性肿瘤的发展提供重要见解。