Establishment of the Uterine-Placental Interface

随着妊娠的进展，生长中的胎儿对氧气和营养的需求增加。为了适应这些需求，子宫-胎盘界面发生了适应。在妊娠早期，滋养层干细胞分化并侵入子宫组织，促进子宫螺旋动脉的重塑。胎盘发育异常，滋养层侵袭不足，会导致妊娠障碍，包括早期妊娠丢失、先兆子痫、宫内生长受限和早产。侵袭性子宫滋养细胞转化失败，尤其是子宫血管，是导致这些严重产科并发症的原因。然而，我们对侵袭性滋养层细胞系的发展机制知之甚少。我们研究方法的基本前提是胎盘位置的调节中存在保守性。我们利用大鼠作为一个模型，因为与包括小鼠在内的其他物种不同，大鼠表现出与人类相似的子宫内滋养层细胞的深度侵袭。人类TS细胞最近被分离并在体外培养，可以被操纵分化为侵袭性滋养细胞，在人类被称为绒毛外滋养细胞(EVT细胞)。人TS细胞是研究滋养层细胞分化调控分子机制的良好模型。我们的长期目标是确定控制侵袭性滋养层细胞系分化的保守调控因子。在初步研究中，我们使用大鼠子宫-胎盘界面的单细胞RNA测序(scRNA-seq)来确定侵袭性滋养细胞谱系的候选调节因子。我们发现细胞周期蛋白依赖性激酶抑制因子1C(CDKN1C)是一种在大鼠和人的侵袭性滋养层细胞中唯一表达的保守转录产物。CDKN1C是多种发育系统中细胞增殖、内复制和分化的关键调节因子。在目标1中，将使用功能丧失的方法来研究CDKN1C在人类TS细胞分化为侵袭性EVT细胞谱系中的作用。我们将研究CDKN1C影响的结构、转录和功能过程。在目标2中，我们利用功能丧失的大鼠模型来研究CDKN1C在胎盘形成的生理环境中的作用。这个项目将在堪萨斯大学医学中心(KUMC)完成，由迈克尔·J·苏亚雷斯博士和一个由杰出生物医学科学家组成的指导团队指导。已经制定了一项培训计划，以促进发展必要的技术熟练程度和批判性思维技能，以设计和执行有效地解决有意义的生物学问题的实验。苏亚雷斯实验室、生殖和围产期研究所以及KUMC的病理和实验室医学系代表着丰富的科学环境，将提供出色的研究生培训和研究机会，以获得对侵袭性滋养细胞谱系的调节和子宫-胎盘界面建立的新见解。

As pregnancy progresses, the oxygen and nutrient needs of the growing fetus increase. To accommodate these needs, adaptations occur at the uterine-placental interface. Early in pregnancy, trophoblast stem (TS) cells differentiate and invade into the uterine tissue to facilitate remodeling of uterine spiral arteries. Abnormal placenta development with insufficient trophoblast invasion leads to pregnancy disorders including early pregnancy loss, preeclampsia, intrauterine growth restriction, and pre-term birth. The failure of invasive trophoblast cell transformation of the uterus and especially the uterine vasculature is the causative event leading to these devastating obstetrical complications. However, we know little about the mechanisms underlying development of the invasive trophoblast cell lineage. The underlying premise of our research approach is that conservation exists in the regulation of placentation. We utilize the rat as a model because unlike other species, including the mouse, the rat exhibits deep intrauterine trophoblast cell invasion similar to the human. Human TS cells have recently been isolated and propagated in vitro and can be manipulated to differentiate into invasive trophoblast, which in the human are referred to as extravillous trophoblast (EVT) cells. Human TS cells are an excellent model for investigating molecular mechanisms regulating trophoblast cell differentiation. Our long-range goal is to identify conserved regulators controlling differentiation of the invasive trophoblast cell lineage. In a preliminary study, we used single-cell RNA sequencing (scRNA-seq) of the rat uterine-placental interface to identify candidate regulators of the invasive trophoblast cell lineage. We identified cyclin dependent kinase inhibitor 1C (CDKN1C) as a conserved transcript uniquely expressed in invasive trophoblast cells of the rat and human. CDKN1C is a key regulator of cell proliferation, endoreduplication, and differentiation in several developmental systems. In Aim 1, a loss-of-function approach will be used to investigate the involvement of CDKN1C in human TS cell differentiation into the invasive EVT cell lineage. We will examine structural, transcriptomic, and functional processes impacted by CDKN1C. In Aim 2, we utilize a loss-of-function rat model to examine the role of CDKN1C in the physiological context of placentation. This project will be completed at the University of Kansas Medical Center (KUMC) under the guidance of Dr. Michael J Soares and a mentoring team of outstanding biomedical scientists. A training plan has been formulated to facilitate the development of technical proficiencies and critical thinking skills necessary to devise and execute experimentation that effectively addresses a meaningful biological question. The Soares Laboratory, the Institute for Reproduction and Perinatal Research, and the Department of Pathology and Laboratory Medicine at KUMC represent a rich scientific environment that will provide outstanding graduate training and a research opportunity to gain new insights into the regulation of the invasive trophoblast cell lineage and the establishment of the uterine-placental interface.