Germ Plasm Aggregation and Compaction in the Early Zebrafish Embryo

早期斑马鱼胚胎中胚芽质的聚集和压缩

• 批准号: 8784578
• 负责人: Celeste Chloe Eno
• 金额: $ 3.1万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8784578
• 关键词: Actins; Address; Affect; Animals; Auras; Caenorhabditis elegans; Case Study; Cell Communication; Cell Cycle; Cell Differentiation process; Cells; Code; Cytoskeleton; DNA Sequence Rearrangement; Data; Development; Distal; Drosophila genus; Drug usage; Embryo; Embryonic Development; F-Actin; Fertilization; Genes; Germ; Germ Cells; Image; Imagery; In Vitro; Inherited; Injection of therapeutic agent; Intracellular Transport; Laboratories; Lead; Life; Mammals; Messenger RNA; Microfilaments; Microtubules; Modeling; Motor; Movement; Mutation; Myosin ATPase; Myosin Type II; Oocytes; Phenotype; Phylogenetic Analysis; Play; Process; Proteins; Protocols documentation; RNA; Reagent; Reproduction; Research; Role; Slide; Structure; Structure of primordial sex cell; System; Takeda brand of pioglitazone hydrochloride; Technology; Testing; Zebrafish; carcinogenesis; cell determination; cell motility; egg; forward genetics; inhibitor/antagonist; insight; member; mutant; novel; particle; pluripotency; public health relevance; segregation; stemness; teleost

DESCRIPTION (provided by applicant): Germ plasm movement and early acto-myosin movement in the Zebrafish embryo. One of the earliest cell-fate decisions in animal development is the determination of primordial germ cell (PGCs) differentiation, which occurs via inductive cell-cell interactions (e.g. mammals) or preformation (e.g. teleosts, Drosophila, C. elegans). Preformative (maternally inherited) germ plasm is a specialized structure made up of ribonucleoparticles (RNPs), proteins and often associated with cytoskeletal components. The zebrafish model is excellent for studying the movement of germ plasm in early embryogenesis. The transparent embryos are easily manipulated using drugs, as well as morpholino and RNA injections. Recently, members of our laboratory have refined a protocol for manipulation of maternal factors acting in the embryo by injection of reagents into oocytes undergoing in vitro maturation, which has opened the possibility of manipulation prior to and immediately after fertilization. My preliminary data suggest that phosphomyosin is present in germ plasm RNPs during their multimerization prior to and during furrow formation, and that these RNPs reside on F- actin. We propose a mechanism by which myosin II-driven F-actin sliding aggregates germ plasm particles and moves the aggregates into the first two forming furrows. Later, during furrow maturation, germ plasm RNPs continue to undergo multimerization until they form compact masses at the distal ends of these furrows. A maternal effect lethal mutant, aura, does not have the concentric actin rings seen in wild type embryos and do not properly aggregate germ plasm RNPs. This suggests that the protein aura codes for, Mid1ip1L, is involved in the cytoskeletal dynamics of germ plasm early movement. I plan to address these hypotheses by characterizing germ plasm aggregation and recruitment on actin filaments prior to and at furrow initiation, and determining the role Mid1ip1L plays in early cytoskeletal dynamics. The proposed hypothesis of GP RNP movement will provide details on a novel mechanism for the movement of such cellular determinants via the action of a myosin motor on an actin cytoskeletal network. The mechanisms studied will lead to understanding the proper movement of PGC-determining factors, relating to cell stemness, reproduction, carcinogenesis and pluripotency.

描述（由申请人提供）：斑马鱼胚胎中的种质运动和早期肌动球蛋白运动。动物发育中最早的细胞命运决定之一是原始生殖细胞（PGC）分化的决定，其通过诱导细胞间相互作用（例如哺乳动物）或预形成（例如硬骨鱼、果蝇、线虫）发生。预成（母系遗传）种质是一种由核糖核颗粒（RNP）、蛋白质组成的特殊结构，通常与细胞骨架成分相关。斑马鱼模型非常适合研究早期胚胎发生中种质的运动。使用药物以及吗啉和 RNA 注射可以轻松操纵透明胚胎。最近，我们实验室的成员完善了一种通过将试剂注射到体外成熟的卵母细胞中来操纵作用于胚胎的母体因素的方案，这开启了在受精之前和之后立即进行操纵的可能性。我的初步数据表明，磷酸肌球蛋白在沟形成之前和期间的多聚化过程中存在于种质 RNP 中，并且这些 RNP 驻留在 F-肌动蛋白上。我们提出了一种机制，肌球蛋白 II 驱动的 F-肌动蛋白滑动聚集种质颗粒并将聚集物移动到前两个形成的沟槽中。随后，在沟成熟期间，种质 RNP 继续进行多聚化，直到它们在这些沟的远端形成致密的团块。母体效应致死突变体 aura 不具有野生型胚胎中所见的同心肌动蛋白环，并且不能正确聚集种质 RNP。这表明编码的蛋白aura Mid1ip1L参与了种质早期运动的细胞骨架动力学。我计划通过表征沟起始之前和起始时肌动蛋白丝上的种质聚集和募集特征，并确定 Mid1ip1L 在早期细胞骨架动力学中发挥的作用来解决这些假设。所提出的 GP RNP 运动假设将提供有关通过肌球蛋白马达对肌动蛋白细胞骨架网络的作用来移动此类细胞决定因素的新机制的细节。研究的机制将有助于了解与细胞干性、繁殖、癌变和多能性相关的 PGC 决定因子的正确运动。