Morphogenesis: Biophysics and Genetics of Dorsal Closure

细胞片层形态发生在脊椎动物形态发生的发育里程碑中起着至关重要的作用， 包括原肠胚形成和神经管、心脏和上颚的形成。这也是必不可少的， 伤口愈合协调细胞机制和信号级联，驱动和调节 形态发生是至关重要的失调导致发育和伤口愈合缺陷，这可能是致命的。 我们专注于细胞片形态发生是如何供电，调节和协调的基础生物学 在黑腹果蝇的背部闭合过程中。分子、细胞和组织结构的保存 使闭包成为一个理想的模型系统，用于询问形态发生的分子基础。 在闭合过程中，侧表皮片推进以闭合背侧开口。关闭是适合于各种各样的 不同的实验方法，我们开创了关闭作为模型系统的研究，特别是通过 使用实时成像策略。我们确定了有助于关闭的四个过程，并证明， 没有任何一种力量是绝对必要的。因此，闭合是鲁棒的、有弹性的和冗余的， 在后生动物生殖过程中保守的分子成分。我们最近的工作主要集中在离子流 有助于关闭，并提出了一个热力学模型，以了解在关闭过程中的组织重塑。我们 说明来自模式化和极性基因产物的信号如何汇聚在一起来调节细胞形状和变化 以细胞形态为特征。我们启动了一个前瞻性的遗传筛查，直接评估 运动学的封闭和调查封闭的鲁棒性和弹性的遗传基础。140多 先前已知的基因有助于DC，我们已经发现了23个额外的遗传间隔 在试点屏幕中关闭所需的时间仅为²/？果蝇基因组。在未来五年内，我们计划 使用基因发现来识别关闭所需的新基因。我们将使用高分辨率4D成像 为了定量记录野生型和突变动物中表征闭合的细胞形状变化， 然后使用生物物理学策略来确定这些新基因如何有助于力的产生和调节 一个了结我们计划解决的关键概念差距是胚胎模式在建立 细胞和亚细胞结构的特点，胚胎在开始关闭，以及如何离子流 有助于关闭。我们将研究触发关闭和反馈开始的信号（或信号） 补偿闭合过程中遗传或物理损伤的机制。我们将继续 探索力产生细胞骨架组件是如何定位，协调和调节，并研究如何 粘附复合物既传递力又允许细胞运动。 我们是唯一准备解决关键的现存问题的特点基本生物学的细胞片 果蝇的形态发生由于形态发生在分子、细胞和组织水平上高度保守， 我们的工作直接告知脊椎动物发育和伤口愈合中的形态发生。

Cell sheet morphogenesis plays crucial roles in developmental milestones during vertebrate morphogenesis, including gastrulation and the formation of the neural tube, the heart, and the palate. It is also essential for wound healing. Coordination of the cellular machineries and the signaling cascades that drive and regulate morphogenesis is critical – misregulation results in developmental and wound healing defects that can be fatal. We focus on the fundamental biology of how cell sheet morphogenesis is powered, regulated and coordinated during dorsal closure in Drosophila melanogaster. Conservation of molecular, cellular and tissue archictecture make closure an ideal model system for interrogating the molecular basis of morphogenesis. During closure, lateral epidermal sheets advance to close a dorsal opening. Closure is amenable to a wide variety of diverse experimental approaches and we pioneered the study of closure as a model system, especially through the use of live imaging strategies. We identified four processes that contribute to closure and demonstrated that no single force that contributes is absolutely required. Thus, closure is robust, resilient and redundant using molecular components that are conserved across metazoan phylogeny. Our recent work focuses on how ion fluxes contribute to closure and proposes a thermodynamic model to understand tissue remodeling during closure. We address how signals from patterning and polarity gene products converge to regulate cell shape and the changes in cell shape that characterize morphogenesis. We initiated a forward genetic screen that directly assesses the kinematics of closure and investigates the genetic basis for closure's robustness and resilience. More than 140 genes were previously known to contribute to DC and we have already discovered 23 additional genetic intervals that are required for closure in a pilot screen of just ¹/? of the fly genome. During the next five years we plan to use gene discovery to identify new genes that are required for closure. We will use high-resolution 4D imaging to document quantitatively the cellular shape changes that characterize closure in wild type and mutant animals, then use biophysical strategies to determine how these new genes contribute to force production and regulation of closure. Key conceptual gaps we plan to address are what roles embryonic patterning plays in establishing the cellular and subcellular architectures that characterizes the embryo at the onset of closure and how ion fluxes contribute to closure. We will investigate the signal (or signals) that triggers the onset of closure and feedback mechanisms that compensate for genetic or physical insults to the progress of closure. We will continue to explore how force-generating cytoskeletal components are positioned, coordinated and regulated and study how adhesion complexes both transmit forces and allow cell movements. We are uniquely poised to address key extant questions that characterize the basic biology of cell sheet morphogenesis in flies. Because morphogenesis is highly conserved at the molecular, cellular and tissue levels, our work directly informs vertebrate morphogenesis in development and wound healing.