Mechanisms of Embryonic Patterning and Lineage Specification

胚胎模式和谱系规范的机制

• 批准号: 0318768
• 负责人: Laurence Etkin
• 金额: $ 37.5万
• 依托单位: University of Texas, M.D. Anderson Cancer Center
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-08-01 至 2006-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0318768&HistoricalAwards=false
• 关键词: Mechanisms; Embryonic; Patterning; Lineage; Specification

0318768EtkinsI. Intellectual merit of the proposed studyIn the frog, Xenopus laevis, localized maternal RNAs and proteins play important roles in early embryogenesis. In a large scale screen for vegetally localized maternal RNAs the cDNA encoding fatvg was cloned. Fatvg is localized through both the METRO (Early) and late pathways and is associated with the germ plasm in cleavage stage embryos. It is related to a group of mammalian proteins that include adipocyte differentiation related protein (ADRP) and TIP47 that have diverse functions including transport of lipid bodies, regulation of signaling pathways, and molecular trafficking within a variety of cell types. A loss of function analysis of fatvg using antisense oligodeoxynucleotides demonstrated that fatvg plays a dual role in dorsal/ventral patterning and in the specification of the germ cell lineage. The data also show that this dual effect is through the inability of maternal dorsalizing and germ cell determinants to segregate properly in fatvg?depleted embryos. This indicates that both the determinants specifying the germ cell lineage and the dorsal/ventral axis may utilize a common mechanism in segregating their products in the embryo or that their functions are regulated through a common pathway. It is likely, that the mechanism involved in the transport of dorsal and germ cell determinants relies on the movement of vesicles that carry these factors. This is consistent with the observations that fatvg protein is detected coating vesicle-like structures located at the vegetal cortex. This represents a new and novel mechanism involved in regulating germ cell specification and dorsal?ventral patterning. Based on the potential function of fatvg related proteins in molecular trafficking in mammalian cells it is hypothesized that fatvg is a key player in initiating the molecular pathways responsible for germ line specification and dorsal ventral patterning through its role regulating molecular trafficking. This hypothesis will be tested by carrying out the following specific aims: A. To analyze the co localization of fatvg protein with dorsalizing factors and germ cell determinants on cellular structures and how this is altered in fatvg depleted embryos; B. To determine the relationship between fatvg containing vesicles, the cytoskeleton and molecular motors; C. To identify the interacting proteins through which Fatvg functions.II. Broader Impact resulting from the proposed study.The role of fatvg in both patterning and cell lineage specification through its role in molecular trafficking is unique and will illistrates a novel mechanism that integrates both processes. This would be an important contribution to the understanding of early developmental mechanisms and would have a broad impact on the fields of developmental biology, cell biology, and embryology. In addition to the potential scientific advance, the proposed project will involve the training of undergraduates (summer students in the laboratory), graduate students, and postdoctoral scientists. This is an important aspect of our work as scientists and how workers in this field relate to society.

0318768 etkinsi。在非洲爪蟾（Xenopus laevis）中，定位的母体rna和蛋白质在早期胚胎发生中起着重要作用。在植物定位的母体rna的大规模筛选中，克隆了编码fatvg的cDNA。Fatvg定位于METRO（早期）和晚期通路，并与卵裂期胚胎的种质有关。它与包括脂肪细胞分化相关蛋白（ADRP）和TIP47在内的一组哺乳动物蛋白有关，这些蛋白具有多种功能，包括脂质体的运输、信号通路的调节以及各种细胞类型内的分子运输。利用反义寡脱氧核苷酸对fatvg进行的功能缺失分析表明，fatvg在生殖细胞的背侧/腹侧模式和谱系中起双重作用。数据还表明，这种双重效应是通过母体背细胞和生殖细胞决定因子无法在fatvg中正确分离而产生的。枯竭的胚胎。这表明决定生殖细胞谱系和背/腹轴的决定因子在胚胎中分离产物时可能使用共同的机制，或者它们的功能是通过共同的途径调节的。很可能，背细胞和生殖细胞决定因子的运输机制依赖于携带这些因子的囊泡的运动。这与在植物皮层的囊泡样结构上检测到脂肪蛋白的观察结果是一致的。这代表了一种新的和新颖的机制参与调节生殖细胞的规格和背？腹侧模式。基于fatvg相关蛋白在哺乳动物细胞分子运输中的潜在功能，我们假设fatvg通过调节分子运输的作用，在启动负责生殖系规范和背腹模式的分子途径中起关键作用。这一假设将通过以下具体目的进行验证：A.分析脂肪蛋白与细胞结构上的dorsalizing因子和生殖细胞决定因子的共定位，以及在脂肪耗尽的胚胎中这是如何改变的；B.确定含脂肪囊泡、细胞骨架和分子马达之间的关系；C.鉴定Fatvg发挥作用的相互作用蛋白。建议研究的更广泛影响。通过其在分子运输中的作用，fatvg在模式和细胞谱系规范中的作用是独特的，并将阐明整合这两个过程的新机制。这将是对早期发育机制理解的重要贡献，并将对发育生物学、细胞生物学和胚胎学领域产生广泛影响。除了潜在的科学进步外，拟议的项目还将涉及本科生（实验室的暑期学生），研究生和博士后科学家的培训。这是我们作为科学家工作的一个重要方面，也是这个领域的工作者与社会的关系。