Differential Response to the Dpp Morphogen

对 Dpp 形态发生素的差异反应

基本信息

批准号：
8061669
负责人：
CHRISTINE A RUSHLOW
金额：
$ 29.27万
依托单位：
NEW YORK UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2002
资助国家：
美国
起止时间：
2002-04-01 至 2012-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8061669
关键词：
Address Affect Affinity Amino Acids Animals Antibodies Binding Biological Assay Candidate Disease Gene Chimeric Proteins Chromatin Congenital Abnormality DNA Binding DNA Polymerase II Data Dependence Deposition Development Developmental Process Disease Dorsal Drosophila genus Embryo Embryonic Development Enhancers Event Fertilization Gene Activation Gene Dosage Gene Expression Gene Targeting Genes Genetic Transcription Genome Genomics Germ Histones Human Insecta Life Link Malignant Neoplasms Mediating MicroRNAs Molecular Molecular Profiling Mutate Nucleic Acid Regulatory Sequences Oocytes Phenotype Play Positioning Attribute Process Proteins RNA RNA Degradation RNA Interference Reporter Genes Role Sampling Site Smad Proteins Smad protein Staging Structure Tertiary Protein Structure Testing Time Transcript Wasps Zinc Fingers activating transcription factor blastocyst dorsal proteins human disease interest morphogens mutant promoter public health relevance research study response

项目摘要

DESCRIPTION (provided by applicant): In all animals the initial events of embryogenesis are controlled by maternal gene products that are deposited into the developing oocyte. At some point after fertilization, control of embryogenesis is transferred to the zygotic genome in a process called the maternal to zygotic transition (MZT). During this time maternal RNAs are degraded and zygotic RNAs are transcribed. Although progress has been made on the mechanisms underlying RNA degradation (Giraldez et al., 2006), the activators of the zygotic genome have remained elusive. A hint came from the discovery that many Drosophila zygotic genes share a cis-regulatory motif related to CAGGTAG (ten Bosch et al.,2006; De Renzis et al., 2007). We recently isolated a zinc-finger protein, Zelda, which binds specifically to these sites. Mutant embryos lacking maternal zelda transcripts fail to activate the transcription of a sample of zygotic genes, and are defective in several aspects of the cellularization process, which corresponds to the point at which embryos can no longer survive on maternal products alone (Merrill et al., 1988). Our preliminary results suggest that Zelda activates batteries of genes during the MZT, each responsible for a key developmental process. Zelda may activate early-transcribed microRNAs that mediate maternal RNA degradation, thus providing a link between the two hallmark events of the MZT. Building on our preliminary data, we will further characterize the role of Zelda in the MZT. How many genes does Zelda activate and which early genes are independent of Zelda? We will use a genomics approach in Aim 1 to determine all Zelda targets in the early embryo. How many genes does Zelda activate, and are there groups of genes not regulated by Zelda? In Aim 2 we ask whether Zelda plays an instructive or permissive role, or both, in activating target genes, and how it interacts with other key regulators such as Dorsal and Dpp to activate their target genes. In Aim 3 we investigate the structure and function of conserved Zelda protein domains, and test whether there is Zelda function in the long germ Nasonia wasp and if it plays a similar role in activating the zygotic genome. Finally, we address mechanistic questions regarding the timing of genome activation in Aim 4, and the possible role of Zelda in reversing the initial silencing of the genome. The experiments outlined in this proposal have the potential to advance greatly our understanding of the mechanisms underlying the MZT. PUBLIC HEALTH RELEVANCE: The study of the molecular mechanisms underlying basic developmental processes is relevant to understanding the cause and progression of human diseases such as cancer, and human disorders such as birth defects.

描述（由申请人提供）：在所有动物中，胚胎发生的初始事件受母体基因产物的控制，这些产妇沉积在发育中的卵母细胞中。在受精后的某个时刻，在称为母体至二胞胎过渡（MZT）的过程中将胚胎发生的控制转移到了二聚基因组中。在此期间，孕产妇RNA降解并转录合子RNA。尽管在RNA降解的基础机制上取得了进展（Giraldez等，2006），但合子基因组的激活因素仍然难以捉摸。一个暗示来自发现，许多果蝇基因具有与Caggtag相关的顺式调节基序（Ten Bosch等，2006; De Renzis等，2007）。我们最近分离了一种锌指蛋白Zelda，该Zelda专门与这些位点结合。缺乏母体ZELDA转录本的突变胚胎无法激活二吻合基因样品的转录，并且在细胞化过程的几个方面有缺陷，这对应于胚胎无法单独使用胚胎生存在孕妇产物上的点（Merrill等，1988）。我们的初步结果表明，Zelda在MZT期间激活基因的电池，每个基因都负责关键发育过程。 Zelda可能会激活介导母体RNA降解的早期转录的microRNA，从而在MZT的两个标志事件之间提供联系。在我们的初步数据的基础上，我们将进一步描述Zelda在MZT中的作用。 Zelda激活多少基因，哪些早期基因独立于Zelda？我们将在AIM 1中使用基因组学方法来确定早期胚胎中的所有Zelda靶标。 Zelda激活了多少个基因，并且是否存在不受Zelda调节的基因组？在AIM 2中，我们询问Zelda在激活靶基因以及它如何与其他关键调节剂（如背侧和DPP）相互作用以激活其靶基因时扮演具有启发性或宽容的作用，还是在激活靶基因的激活中发挥作用。在AIM 3中，我们研究了保守的Zelda蛋白结构域的结构和功能，并测试长胚鼻虫WASP中是否具有Zelda功能，并且在激活二染色体基因组中起着相似的作用。最后，我们解决了有关AIM 4基因组激活时间的机理问题，以及Zelda在逆转基因组初始沉默中的可能作用。该提案中概述的实验有可能极大地促进我们对MZT基础机制的理解。公共卫生相关性：对基本发展过程基础的分子机制的研究与了解人类疾病（如癌症）以及人类疾病（如先天性缺陷）的原因和进展有关。