X-linked Dyskeratosis Congenita and ribosomal frameshifting

X连锁先天性角化不良和核糖体移码

• 批准号: 8894573
• 负责人: Jonathan D Dinman
• 金额: $ 61.73万
• 依托单位: UNIV OF MARYLAND, COLLEGE PARK
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-01 至 2018-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8894573
• 关键词: Ablation; Address; Affect; Affinity; Binding Proteins; Biological Markers; Biological Process; Candidate Disease Gene; Cells; Collaborations; Data; Databases; Defect; Development; Diagnostic; Disease; Exhibits; Foundations; Functional disorder; Gap Junctions; Gene Expression; Gene Targeting; Genes; Genetic; Global Change; Health; Hematopoietic; Hematopoietic stem cells; Human; Impairment; Inherited; Laboratories; Ligands; Link; Malignant Neoplasms; Mediating; Medical; Messenger RNA; MicroRNAs; Modification; Molecular; Mus; Mutation; Nonsense Codon; Pancytopenia; Pathogenesis; Pathway interactions; Patients; Process; Prognostic Marker; Protein Biosynthesis; Proteins; Pseudouridine; Publishing; RNA Splicing; Regulator Genes; Research; Resolution; Ribosomal Frameshifting; Ribosomal RNA; Ribosomes; Role; Signal Transduction; Syndrome; System; Telomere Maintenance; Telomere Shortening; Telomeric Repeat Binding Protein 2; Testing; Therapeutic; Therapeutic Intervention; Transfer RNA; Translating; Translations; Uridine; Validation; Work; X-Linked Dyskeratosis Congenita; Yeast Model System; Yeasts; base; bone marrow failure syndrome; cis acting element; induced pluripotent stem cell; mRNA Decay; mRNA Stability; mRNA Transcript Degradation; mouse model; novel; novel diagnostics; novel strategies; novel therapeutics; programs; protein expression; research study; stem cell differentiation; synthetic protein; transcriptome sequencing

DESCRIPTION (provided by applicant): Abnormalities in ribosome function that are implicated in both congenital and acquired bone marrow failure syndromes in humans are classified under the broad umbrella of ribosomopathies. A recent collaboration between our two laboratories has initiated a completely new avenue of research by establishing an evolutionarily conserved role for ribosome modifications mediated by the pseudouridine synthase dyskerin in specific aspects of translation control. The functional role of pseudouridine (�) modifications is of great medical importance as mutations in DKC1, the gene encoding for dyskerin, are found in a number of diseases including X-linked dyskeratosis congenita (X-DC), Hoyeraal-Hreidarsson syndrome, and numerous cancers. Importantly, our published work has identified that the decreased affinity of rRNA � defective ribosomes for tRNAs results in increased rates of programmed -1 ribosomal frameshifting (-1 PRF), a molecular mechanism that is emerging as an important regulator of gene expression. This proposal seeks to test the hypothesis that global changes in -1 PRF affect the expression of specific subsets of mRNAs encoding key hematopoietic factors, that may contributing to some of the pathological features associated with X- DC. Support for this hypothesis is evident from our extensive published and unpublished findings showing that increased rates of -1 PRF promotes rapid degradation of specific mRNAs through the Nonsense-Mediated mRNA Decay (NMD) pathway. Furthermore, we have demonstrated that rRNA � levels are impaired in hematopoietic cells from X-DC patients harboring distinct DKC1 mutations. Importantly, our preliminary and published data also suggest that one important functional class of mRNAs involved in telomere maintenance is regulated by this mechanism in both yeast and human cells and is disrupted in X-DC patients, thus linking rRNA � defects and telomere shortening. By utilizing X-DC as a disease paradigm and combining three model systems, yeast, mouse and humans, in this proposal we will extend our novel findings and identify the repertoire of mRNAs that underlie bone marrow failure associated with ribosome dysfunction and determine the therapeutic potential of inhibiting NMD and -1 PRF in X-DC. Aim 1 of this proposal seeks to identify the repertoire of mRNAs whose expression is affected by rRNA � defects in yeast, mouse and human cells using two complementary approaches. Aim 2 will determine the mechanisms through which impaired rRNA � alters expression of -1 PRF containing mRNAs. Aim 3 is oriented towards determining the therapeutic potential of targeting NMD and -1 PRF in X-DC. By the end of the proposed studies, we will have 1) established a new paradigm for understanding ribosomopathies, 2) identified specific genes that can be used as biomarkers and targeted for therapeutic intervention, and 3) explored novel approaches to treat this class of diseases.

描述（由申请人提供）：与人类先天性和后天性骨髓衰竭综合征有关的核糖体功能异常被归类在核糖体病的大范围内，我们两个实验室最近的合作启动了一条全新的研究途径。建立了由假尿苷合酶 Dyskerin 介导的核糖体修饰在翻译控制的特定方面的进化保守作用。假尿苷 (�) 修饰的功能作用是。 DKC1（编码角化蛋白的基因）突变存在于许多疾病中，包括 X 连锁先天性角化不良 (X-DC)、Hoyeraal-Hreidarsson 综合征和多种癌症，因此具有重要的医学意义。重要的是，我们发表的工作已经确定了这一点。 rRNA � 有缺陷的核糖体与 tRNA 的亲和力导致程序性 -1 核糖体移码 (-1 PRF) 的速率增加，这是一种正在出现的分子机制作为基因表达的重要调节因子，本提案旨在检验以下假设：-1 PRF 的整体变化会影响编码关键造血因子的特定 mRNA 子集的表达，这可能导致与 X-DC 相关的一些病理特征。我们已发表的广泛且未发表的研究结果表明，-1 PRF 的增加会通过无义介导的 mRNA 衰减 (NMD) 途径促进特定 mRNA 的快速降解，这一假设得到了明显的支持。重要的是，我们的初步和发表的数据还表明，参与端粒维持的一类重要功能的 mRNA 在酵母和人类细胞中都受到这种机制的调节，并且在 X 中被破坏。 -DC 患者，从而将 rRNA 缺陷与端粒缩短联系起来。通过利用 X-DC 作为疾病范例并结合酵母、小鼠和人类三种模型系统，在本提案中，我们将扩展我们的新发现并确定与核糖体功能障碍相关的骨髓衰竭的 mRNA 库，并确定在 X-DC 中抑制 NMD 和 -1 PRF 的治疗潜力。该提案的目标 1 旨在确定其表达受 rRNA 缺陷影响的 mRNA 库。使用两种互补方法对酵母、小鼠和人类细胞进行研究，目的 2 将确定受损 rRNA 改变含有 -1 PRF 的 mRNA 的机制，目标 3 旨在确定治疗方法。在 X-DC 中靶向 NMD 和 -1 PRF 的潜力 在拟议的研究结束时，我们将 1) 建立理解核糖体病的新范式，2) 确定可用作生物标志物并针对治疗干预的特定基因。 ，以及3）探索治疗此类疾病的新方法。