"Role of Pitx3 signaling cascades in the regulation of Xenopus eye, laterality, and somite development"

“Pitx3 信号级联在非洲爪蟾眼睛、侧向性和体节发育调节中的作用”

• 批准号: 203549-2012
• 负责人: Crawford, Michael
• 金额: $ 1.89万
• 依托单位: University of Windsor
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=569963
• 关键词: Role; Pitx3; signaling; cascades; regulation

Surprisingly, much of what we have learned about human eye development was first pioneered in studies and manipulations of amphibian embryos. The developmental, structural, and genetic similarities are striking: irrespective of whether you study human, mouse, fish or frog, the same genes interact to produce similar structures. For example, mutation of the human PITX3 homeobox gene results in a failure of lenses to form or in congenital cataracts. The same issues can be re-capitulated in developing mouse, frog, and even fish embryos, where the genes and processes that are involved can be studied and manipulated. The benefit of studying the genes in frog is that the embryos are comparatively large, they develop externally (where you can see them), and they can be cheaply manipulated. The genome is nearly sequenced for the frog Xenopus, and there are many useful probes and techniques for studying eye development in this species, so the organism is useful for testing our theories regarding human eye development and disease. During our recent studies of the role of Pitx3 in frog, we discovered that the gene plays a role not only in eye development, but also in organ asymmetry (heart, gall bladder, gut), and vertebrae. We have identified some of the genes that Pitx3 controls, and these genes play a role in establishing the embryonic body plan, as well as regulating some of the processes important to cell shape, structure, and activity. We have developed strategies to assess how the Pitx3 signaling cascade unfolds to control development and health of the eye, as well as the agenda for development of visceral organs and spine. We are requesting funds to continue this work and to study how Pitx3 turns on some downstream target genes, while turning off others. We hope to reach a better understanding of how the activity of one gene installs an agenda for development. Preliminary work using our newly developed protocol using a flow cytometry based approach to asses Pitx3 effects upon individual cells and genes has produced a number of downstream signaling cascades that we need to test and manipulate in order to refine our understanding of how early events are regulated in vertebrate embryos.

令人惊讶的是，我们所了解的关于人眼发育的大部分知识首先是在两栖动物胚胎的研究和操作中首创的。在发育、结构和遗传方面的相似性是惊人的：无论你研究的是人、老鼠、鱼还是青蛙，相同的基因相互作用产生相似的结构。例如，人类PITX3同源框基因的突变导致晶状体不能形成或导致先天性白内障。同样的问题可以在老鼠、青蛙甚至鱼的胚胎发育中重新出现，在这些胚胎中，涉及的基因和过程可以被研究和操纵。研究青蛙基因的好处是，胚胎相对较大，它们在外部(你可以看到它们的地方)发育，而且可以廉价地操纵它们。非洲爪蛙的基因组几乎被测序了，而且有许多有用的探针和技术来研究这种物种的眼睛发育，所以这种生物对检验我们关于人类眼睛发育和疾病的理论是有用的。在我们最近对青蛙中Pitx3的作用的研究中，我们发现该基因不仅在眼睛发育中发挥作用，而且在器官不对称(心脏、胆、肠道)和脊椎中也发挥作用。我们已经确定了一些由Pitx3控制的基因，这些基因在建立胚胎身体计划以及调节一些对细胞形状、结构和活动至关重要的过程中发挥了作用。我们已经制定了策略，以评估Pitx3信号级联如何展开，以控制眼睛的发育和健康，以及内脏器官和脊柱的发育议程。我们正在申请资金，以继续这项工作，并研究Pitx3如何打开一些下游靶基因，同时关闭其他基因。我们希望更好地理解一个基因的活动如何为发展制定议程。使用我们新开发的方案的初步工作使用基于流式细胞术的方法来评估Pitx3对单个细胞和基因的影响，已经产生了许多下游信号级联，我们需要测试和操纵这些信号，以完善我们对脊椎动物胚胎中早期事件是如何调控的理解。