Deciphering cellular and molecular pathways controlling invasive trophoblast differentiation

背景：胎盘的正确形成是哺乳动物繁殖成功的重要决定因素之一。胎盘在母亲和胎儿之间形成机械和生理联系，支持生长和发育。如果发育不正常，可能会对母亲和后代造成严重的问题，包括死亡。胎盘是在一组特殊的细胞后发育出来的，这些细胞是胚泡的一部分，‘侵入’子宫壁，附着在胚胎上。这些细胞被称为滋养层细胞，然后扩张以创建细胞结构，使母亲和胎儿之间能够转移氧气和营养，并进一步指导当地对发育中的胎儿的耐受环境。尽管胎盘很重要，但我们对胎盘形成的关键早期阶段所涉及的细胞和分子事件仍然知之甚少。最新进展：在过去的五年里，我的实验室研究了ADAM蛋白酶和低氧暴露是否控制了侵袭性滋养细胞的功能。使用3D胎盘外植体系统，概括了胎盘发育过程中发生的许多细胞事件，以及最先进的单细胞测序，我们证明了特定的ADAMS促进滋养层细胞侵袭，低氧加速滋养层细胞分化为侵袭性亚型。目的：基于我的实验室的长期目标，即确定和表征在滋养细胞生物学和胎盘发育中重要的新的分子和细胞过程，我将通过两个短期目标推进这一目标：1)检测ADAM蛋白水解酶是否控制EVT分化；以及2)识别低氧调控的控制EVT分化的途径。方法：拟议的研究将检验ADAM蛋白水解酶和低氧压促进滋养层细胞沿侵袭性绒毛外途径分化的假说。使用滋养层器官培养和3D胎盘外植体系统，我将结合最先进的单细胞测序和基因编辑方法来确定ADAM蛋白水解酶是否协调滋养层分化，并确定低氧如何驱动侵袭性滋养层规范。HQP：我打算在这个支持的时间表上培训一个由8个HQP组成的不同的小组。在这些HQP的培训中，我将实施公平和包容的招聘和指导做法。影响：这些研究将提高我们对滋养细胞生物学和胎盘形成的分子机制的理解，目前对此知之甚少。这项工作还将产生关于亚当蛋白水解酶和氧气感应系统的新知识，这些知识可能在其他细胞系统和器官中保守，因此可能间接有助于干细胞和发育生物学领域。

BACKGROUND: Correct formation of the placenta is one of the most important determinants of successful reproduction in mammals. The placenta forms the mechanical and physiologic link between mother and fetus, supporting growth and development. If it does not develop properly, there can be serious problems, including death, for both mother and offspring. The placenta develops after a special group of cells that are part of the blastocyst `invade' into the wall of the uterus, attaching the embryo. These cells, called trophoblasts, then expand to create cellular structures that enable transfer of oxygen and nutrients between mother and fetus, and further instruct a local environment of tolerance towards the developing fetus. Despite the importance of the placenta, we still have a poor understanding of the cellular and molecular events involved in the critical early stages of its formation. RECENT PROGRESS: Over the past five years, my lab has examined if ADAM proteases and exposure to low oxygen control invasive trophoblast functions. Using 3D placental explant systems that recapitulate many of the cellular events occurring during placental development and state-of-the-art single cell sequencing, we show that specific ADAMs promote trophoblast invasion and low oxygen accelerates trophoblast differentiation into invasive subtypes. OBJECTIVES: Building on my laboratory's long-term objective to identify and characterize novel molecular and cellular processes important in trophoblast biology and placental development, I will advance this via two short-term objectives: 1) testing if ADAM proteases control EVT differentiation; and 2) identifying hypoxia-regulated pathways controlling EVT differentiation. METHODOLOGY: The proposed studies will test the hypothesis that ADAM proteases and low O2 tension promote trophoblast differentiation along the invasive extravillous pathway. Using trophoblast organoid cultures and 3D placental explant systems, I will incorporate state-of-the-art single cell sequencing and gene-editing methods to determine if ADAM proteases coordinate trophoblast differentiation and identify how hypoxia drives invasive trophoblast specification. HQP: I intend to train a diverse group of 8 HQP over the timeline of this support. In the training of these HQP, I will implement equitable and inclusive recruitment and mentoring practices. IMPACT: These studies will improve our understanding of the molecular mechanisms involved in trophoblast biology and placental formation, of which there is currently little knowledge. This work will also generate new knowledge about ADAM proteases and oxygen-sensing systems that are likely conserved in other cellular systems and organs, and may therefore indirectly contribute to fields of stem cell and developmental biology.