MCA: Defining the role of the small GTPase Rap1 in a slow cell intercalation event in the Drosophila melanogaster eye

该项目将探索一种名为Rap1的蛋白质在驱动形态发生机制中的作用：在所有动物的发育过程中发生的细胞和组织形状和排列的变化，这对它们的形式和功能至关重要。Curtiss实验室通过结合分子遗传学和传统的显微方法来保存组织，为这个项目奠定了基础。然而，由于形态发生是一个在几分钟到几小时内发生的动态过程，因此有必要在活组织中可视化这些过程。Curtiss博士将与伦敦大学学院的Franck Pichaud博士合作，学习最先进的活细胞成像技术，以及如何测量果蝇眼睛形态发生过程中的生物和机械特性。尽管近年来人们对驱动细胞和组织形态发生的机制已经了解了很多，但大部分工作都是在一些相对简单的生物体上完成的，这些生物体含有非常相似的细胞类型。该项目将研究包含多种细胞类型的组织中的形态发生，以了解它们如何共同促进整个组织的形态发生。柯蒂斯博士将把这些最先进的技术和测量知识带回新墨西哥州立大学。在伦敦大学学院的Pichaud博士和新墨西哥州立大学的Charles Shuster博士的建议下，Curtiss博士将对研究生和本科生进行这些技术的培训，这将丰富他们的教育，并为他们提供在未来研究工作中参与顶级竞争所需的技能。近年来，对细胞插层在形态发生中的作用的研究取得了显著进展。这些见解源于活细胞成像、细胞形状、粘附性和收缩性的仔细测量以及数学建模方面同样显著的进步。目前大多数模型关注的是均匀细胞群中的快速细胞插层（几分钟内发生）。利用传统的免疫荧光，Curtiss实验室发现了小GTPase Rap1在锥体细胞缓慢细胞插层中的作用，这种插层发生在数小时内，并且在黑腹果蝇蛹眼发育过程中受到多种细胞类型的影响。Franck Pichaud博士开发了活细胞成像和数学建模方法来理解这一相同的形态发生事件。该项目的目标是让Curtiss博士前往伦敦大学学院的Franck Pichaud博士的实验室学习和应用：1)活细胞成像，以确定Rap1是否影响细胞粘附分子定位、Notch信号和/或视锥细胞嵌入过程中Myosin II的定位；2)定量分析和使用顶点模型来确定Rap1对锥细胞插入过程中先前测量的生物力学特性的影响。Curtiss博士将把这些新技术带回她在新墨西哥州立大学的实验室，并在伦敦大学学院的Pichaud博士和新墨西哥州立大学的Charles Shuster博士的帮助下，指导她的研究生和本科生使用这些技术。实现这些目标将有助于现有的关于所有动物形态发生的知识，并将使学生在未来的研究努力中达到最高水平。该项目由NSF/BIO/MCB细胞动力学和功能计划和NSF建立的刺激竞争性研究计划（EPSCoR）共同资助。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This project will probe the role of a protein called Rap1 in the mechanisms that drive morphogenesis: the changes in cell and tissue shapes and arrangements that occur during development of all animals, and that are essential for their form and function. The Curtiss lab has laid the groundwork for this project by employing a combination of molecular genetics and conventional microscopic approaches on preserved tissues. However, as morphogenesis is a dynamic process that occurs in minutes to hours, it is essential to visualize these processes in living tissues. Dr. Curtiss will collaborate with Dr. Franck Pichaud at University College London to learn state-of-the-art live-cell imaging and how to measure biological and mechanical properties during morphogenesis in eyes of fruit flies. Although a lot has been learned in recent years about the mechanisms that drive morphogenesis of cells and tissues, much of this work has been done on a few relatively simple organisms containing very similar cell types. This project will examine morphogenesis in a tissue containing multiple cell types, to understand how they can work together to promote morphogenesis of the whole tissue. Dr. Curtiss will bring knowledge of these state-of-the-art techniques and measurements back to New Mexico State University. With advice from Dr. Pichaud at University College London and from Dr. Charles Shuster at New Mexico State University, Dr. Curtiss will train graduate and undergraduate students in these techniques, which will enrich their educations and give them the skills needed to compete at top levels in future research endeavors.Recent years have seen remarkable advances in understanding of cell intercalation in morphogenesis. These insights stem from equally remarkable advances in live-cell imaging, careful measurements of cell shape, adhesion, and contractility, as well as mathematical modeling. Most current models focus on fast cell intercalation (occurring in minutes) in homogeneous cell populations. Using conventional immunofluorescence, the Curtiss lab has discovered a role for the small GTPase Rap1 in a slow cell intercalation of cone cells that occurs over hours and with influence from multiple cell types during pupal eye development in Drosophila melanogaster. Dr. Franck Pichaud has developed live-cell imaging and mathematical modeling approaches to understanding this same morphogenetic event. The goals of this project are for Dr. Curtiss to travel to Dr. Franck Pichaud’s lab at University College London to learn and apply: 1) Live-cell imaging to determine whether Rap1 affects cell adhesion molecule localization, Notch signaling, and/or Myosin II localization during cone cell intercalation, and; 2) Quantitative analyses and use of vertex models to determine the effects of Rap1 on previously measured biomechanical properties during cone cell intercalation. Dr. Curtiss will bring these new techniques back to her lab at New Mexico State University, and, with help from Dr. Pichaud at University College London and from Dr. Charles Shuster at New Mexico State University, will instruct her graduate and undergraduate students in these techniques. Achieving these goals will contribute to existing knowledge about morphogenesis in all animals and will enable students to compete at top levels in their future research endeavors.This project is jointly funded by the NSF/BIO/MCB Cell Dynamics & Function Program and the NSF Established Program to Stimulate Competitive Research (EPSCoR).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.