Specialized Translational Control of Stem Cell Differentiation and Embryonic Development

干细胞分化和胚胎发育的专门转化控制

基本信息

批准号：
10611400
负责人：
Maria Barna
金额：
$ 59.11万
依托单位：
STANFORD UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-03-15 至 2026-03-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10611400
关键词：
5&apos Untranslated Regions Area Atlases Attention Biological Biology Bone marrow failure Cell Differentiation process Cell Lineage Cells Cellular biology Cleft Palate Code Complex Congenital Abnormality Cytoplasm Data Development Developmental Biology Developmental Gene Diamond-Blackfan anemia Disease Elements Embryo Embryonic Development Endoderm Endoderm Cell Endowment Enhancers Epithelial Cells Failure Fibroblast Growth Factor Gene Expression Gene Expression Regulation Genetic Genetic Transcription Growth Heterogeneity Human Individual Lactation Life Limb structure Link MAP Kinase Gene Mediating Mesoderm Mesoderm Cell Messenger RNA Milk Proteins Molecular Machines Mus Mutation Organelles PIK3CG gene Paraxial Mesoderm Pathway interactions Pattern Phenotype Play Population Pregnancy Process Production Protein Isoforms Proteins Pseudogenes RNA Splicing RPS27 gene Regulation Regulon Research Ribosomal Proteins Ribosomes Role SHH gene Signal Pathway Signal Transduction Specific qualifier value Specificity Subcellular Spaces System Time Tissues Translating Translational Regulation Translations Variant WNT Signaling Pathway Work cell type embryonic stem cell field study frontier gene regulatory network genetic approach genome-wide genome-wide analysis human embryonic stem cell in vivo interdisciplinary approach mRNA Translation mammalian genome mammary mammary gland development neonate new technology novel paralogous gene postnatal development posttranscriptional preference progenitor programs ribosomopathy sequencing platform spatiotemporal stem cell biology stem cell differentiation stem cells tool

项目摘要

Control of gene expression in space and time plays an important role in enabling cells to “know” where they are in the developing embryo and what to become, a process often referred to as cellular specification. Decades of research have demonstrated numerous layers of regulation in control of gene expression, at both the transcriptional and post-transcriptional level, which coordinate this process. Translational control of gene expression has, on the contrary, received less experimental attention. Most notably, the prevailing dogma has been that at the level of protein production, the ribosome - although an immensely complex molecular machine- possesses a constitutive rather than regulatory function in translating mRNAs. Our findings have established a new field of study by demonstrating that ribosomes are highly regulatory in control of the expression of developmental gene regulatory networks underlying tissue patterning and formation of the mammalian body plan. In our most recent studies, we have identified entire biological pathways in embryonic stem cells represented by the translational preferences of specific ribosomes, that differ in the composition of their ribosomal proteins (RPs) or the interaction of novel ribosome-associated proteins (RAPs) that we have recently identified that directly associate with mammalian ribosomes. We have further shown ribosome heterogeneity in proximity to key cellular organelles as a mechanism to control localized protein production within subcellular space. These findings change our understanding of gene regulation and open a new portal of study into an additional layer of gene expression vital to control of cell specification, tissue patterning, and embryonic development. In this proposal we will undertake a highly multidisciplinary approach to characterize this novel regulatory code for translational control of the circuitry of key developmental networks. In Aim1 we will extend our new roadmap of ribosome heterogeneity indicated by the presence of distinct ribosomes during primary human ES cellular differentiation to an organismal level. In particular, we will leverage novel genetic tools to study ribosome biology in-vivo. Using this approach, we will delineate the mechanisms by which a single RP can control a paramount step in embryonic development, namely sustained paraxial mesoderm formation, and its role in translational control of the WNT signaling pathway, which reflects a novel step in the regulation of a major signaling pathway in development. In Aim2 we will undertake a systems level approach to characterize the role of ribosomes as key regulators of cell fate transitions. We will utilize novel technologies to forcibly and inducibly remove specific RPs selectively from cytoplasmic ribosomes for the first time and assess their individual functions on stem cells differentiation down the mesoderm and endoderm lineages. In Aim3 we will functionally characterize alternative RP paralogs in mammary-glad development for which our compelling preliminary data indicate that they translate distinct subsets of mRNAs during the switch to lactation. We hypothesize that translation control is required to synthesize copious milk proteins critical for neonate sustenance. Defining at a more basic level the specificity and dynamics of ribosome-mediated control gene regulation will be invaluable for our understanding of how deregulations in the ribosome alter accurate control of gene expression underlying human congenital birth defects.

基因表达在空间和时间上的控制对于使细胞“知道”它们在细胞中的位置起着重要作用。胚胎的发育和发育，这个过程通常被称为细胞规范，经过了数十年的研究。转录和转录后均证明了控制基因表达的多层调控相反，协调这一过程的翻译控制却受到较少的关注。最值得注意的是，普遍的教条是在蛋白质生产水平上，核糖体 - 尽管分子机器极其复杂，但在翻译过程中具有构成功能而不是调节功能我们的研究结果证明核糖体在控制方面具有高度调节性，从而建立了一个新的研究领域。哺乳动物组织模式和形成的发育基因调控网络的表达在我们最近的研究中，我们已经确定了胚胎干细胞的整个生物学途径。通过特定核糖体的翻译偏好，其核糖体蛋白（RP）或核糖体的组成不同我们最近发现的新型核糖体相关蛋白（RAP）的相互作用与我们进一步证明了哺乳动物核糖体作为关键细胞器的异质性。这些发现改变了我们对亚细胞空间内局部蛋白质生产的理解。基因调控并为研究对细胞控制至关重要的额外基因表达层开辟了新的研究门户在这项提案中，我们将进行高度多学科的研究。方法来表征这种新颖的监管代码，用于关键发育网络电路的翻译控制。在 Aim1 中，我们将扩展我们的核糖体异质性的新路线图，该路线图由不同核糖体的存在所表明特别是，我们将利用新的遗传工具来研究人类 ES 细胞的初级分化。使用这种方法，我们将描述单个 RP 控制核糖体的机制。胚胎发育中最重要的步骤，即持续的轴旁中胚层形成及其在转化中的作用 WNT信号通路的控制，这反映了调节主要信号通路的新步骤在 Aim2 中，我们将采用系统级方法来描述核糖体作为关键调节因子的作用。我们将利用新技术选择性地强制和诱导地去除特定的 RP。首次研究细胞质核糖体并评估其对干细胞分化的个体功能在 Aim3 中，我们将对 Mammary-glad 中的替代 RP 旁系同源物进行功能表征。我们令人信服的初步数据表明，它们在发育过程中翻译了不同的 mRNA 子集。我们勇敢地说，合成大量的乳蛋白对于哺乳至关重要。在更基本的水平上定义核糖体介导的控制基因的特异性和动态。调控对于我们理解核糖体的失调如何改变基因的精确控制具有无价的价值人类先天性缺陷的表达。