Control of collective cell movement by planar cell polarity signaling

 描述（由申请人提供）：平面细胞极性（PCP）蛋白是一种高度保守的分子系统，用于协调片层内的细胞，在脊椎动物中，这些蛋白控制称为会聚延伸的集体细胞运动。该提案旨在解决脊椎动物五氯苯酚生物学中两个关键的未决问题。1)肌动球蛋白收缩是大多数细胞运动的关键驱动力，但令人惊讶的是，对PCP蛋白和肌动球蛋白收缩之间的联系知之甚少，特别是在脊椎动物中。我们将确定PCP蛋白的作用，在控制的空间和时间模式的肌球蛋白II激活细胞从事会聚延伸。我们将结合联合收割机活成像方法和激光显微切割来研究会聚伸展过程中细胞形状的变化、动态蛋白质定位和细胞皮质张力。2)PCP蛋白的动态定位对其正常功能至关重要，但这些蛋白在会聚延伸期间如何定位以及它们的定位如何驱动集体细胞运动尚不清楚。我们将使用实时成像新的荧光报告，以解决这个问题，在脊椎动物原肠胚形成。 影响力：PCP介导的会聚性延伸对于神经管闭合是必不可少的，PCP基因的突变可能是由神经管闭合失败导致的人类出生缺陷的原因。因此，这里提出的实验将为我们了解人类神经管缺陷，如脊柱裂提供信息。此外，最近的数据表明PCP依赖性会聚延伸在肾小管形态发生中的作用，因此本文提出的实验将为先天性多囊肾病的潜在机制提供新的线索。

 DESCRIPTION (provided by applicant): The Planar Cell Polarity (PCP) proteins are a highly conserved molecular system for coordinating cells within a sheet, and in vertebrate animals, these proteins control collective cell movements termed convergent extension. This proposal seeks to address two key outstanding issues in vertebrate PCP biology. 1) Actomyosin contraction is the key driver of most cell movements, but surprisingly little is yet known about th links between PCP proteins and actomyosin contraction, especially in vertebrates. We will determine the role of PCP proteins in controlling the spatial and temporal patterns of Myosin II activation in cells engaged in convergent extension. We will combine live imaging approaches and laser-microdissection to investigate cell shape changes, dynamic protein localization, and cell cortex tension during convergent extension. 2) The dynamic localization of PCP proteins is central to their normal function, but how these proteins are localized during convergent extension and how their localization drives collective cell movements in unknown. We will use live imaging new fluorescent reporters to address this issue during vertebrate gastrulation. Impact: PCP-mediated convergent extension is essential for neural tube closure, and mutations in PCP genes can be causative for human birth defects that result from failure of neural tube closure. The experiments proposed here will thus inform our understanding human neural tube defects such as spina bifida. In addition, recent data now suggest a role for PCP-dependent convergent extension in the morphogenesis of kidney tubules, so experiments proposed here will shed new light on mechanisms underlying congenital polycystic kidney disease.