Identifying long-range polarity cues using spontaneous mutations in mammals

利用哺乳动物的自发突变识别长程极性线索

• 批准号: 10438096
• 负责人: Maureen Patricia Cetera
• 金额: $ 24.9万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-20 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10438096
• 关键词: Affect; Animals; Architecture; Artificial Organs; Back; Behavior; Biological Models; Cavia; Cell Communication; Cells; Cellular biology; Cilia; Complex; Congenital Heart Defects; Cues; Data; Defect; Development; Developmental Biology; Disease; Drosophila genus; Embryo; Embryonic Development; Ensure; Epidermis; Etiology; Failure; Feedback; Generations; Genes; Genetic; Genetic Screening; Genomics; Goals; Growth; Growth and Development function; Hair follicle structure; Head; Image Analysis; In Vitro; Integral Membrane Protein; Labyrinth; Lesion; Light; Live Birth; Mammals; Methods; Molecular; Morphogenesis; Mus; Mutant Strains Mice; Mutation; Nature; Neural Tube Closure; Organ; Pathway interactions; Pattern; Phenotype; Prize; Process; Proteins; Research; Side; Signal Pathway; Signal Transduction; Skin; System; Tissue Expansion; Tissues; Work; causal variant; congenital heart disorder; developmental disease; extracellular; gene product; genetic analysis; hearing impairment; in vivo; malformation; mutant; novel; planar cell polarity; prenatal therapy

Project Summary/ Abstract Neural tube closure defects and congenital heart defects are common developmental disorders, affecting 1 in 1000 and 1 in 100 live births, respectively. During embryonic development, cells must be able to sense direction and coordinate collective behaviors to avoid these severe malformations. Although the signaling pathway that imparts directionality between neighboring cells is known, uncovering the mechanisms that transmit this information on the order of thousands of cells has stalled. Fortuitously, spontaneous mutations in small mammals have given rise to animals that are prized for region specific disruptions in fur orientation. I hypothesize that the mutations disrupt long-range directional cues. The objective of this proposal is to utilize spontaneous mutations to identify long-range directional cues in the mammalian epidermis. This work will shed light on the etiology of complex congenital diseases, which will assist in the development of in utero therapies and the generation of artificial organs. A key molecular pathway that allows cells to communicate directional information is the Planar Cell Polarity (PCP) pathway, without which severe developmental defects arise. The core pathway consists of three transmembrane proteins that form asymmetric complexes that are localized to opposite sides of a cell. Through both positive extracellular feedback and negative intracellular feedback, this asymmetry is propagated locally but the mechanism that orients asymmetry across entire tissues is poorly understood. Although the core pathway components were identified through forward genetic screens in Drosophila, this method has been less successful in uncovering global polarity cues. The mouse skin provides an ideal system to identify long-range polarity cues. The expansive tissue is decorated with thousands of hair follicles (HFs) that are all oriented in the same direction through a PCP driven process. Remarkably, we showed the back skin is compartmentalized into regional domains that influence the direction of PCP signaling. This data suggests that region specific long-range cues cooperate to coordinate PCP and HF orientation across the entire tissue. In support of this idea, spontaneous mutations in small mammals produce animals with distinct, region-specific disruptions in hair follicle orientation. To investigate whether these mutations affect long-range polarity genes, I will identify the causative mutations through genomic sequencing and characterize the effect the mutations have on tissue polarity using genetics and image analysis. I will then interrogate the ability of the identified proteins to act as long-range polarity cues in vivo and in organotypic skin culture. Upon completion of this study, we will identify and understand new mechanisms that coordinate collective behaviors across great distances during tissue morphogenesis.

项目概要/摘要 神经管闭合缺陷和先天性心脏病是常见的发育障碍，影响 1 % 分别为 1000 例和 100 例活产。在胚胎发育过程中，细胞必须能够感知 指导和协调集体行为，以避免这些严重的畸形。虽然信号 在相邻细胞之间传递方向性的途径是已知的，揭示了这种机制 传输此信息的数千个单元已停止。偶然地，自发突变 小型哺乳动物催生了因特定区域毛皮方向的破坏而受到重视的动物。我 假设突变破坏了长程方向线索。该提案的目的是利用 自发突变来识别哺乳动物表皮中的远程定向线索。这部作品将流淌 了解复杂先天性疾病的病因学，这将有助于宫内疗法的发展 以及人造器官的产生。 允许细胞传递方向信息的关键分子途径是平面细胞 极性（PCP）途径，没有该途径就会出现严重的发育缺陷。核心路径由三个部分组成 跨膜蛋白，形成不对称复合物，定位于细胞的相对两侧。 通过正细胞外反馈和负细胞内反馈，这种不对称性得以传播 但我们对整个组织的不对称定向机制知之甚少。虽然核心 途径成分是通过果蝇的正向遗传筛选来鉴定的，该方法较少 成功地揭示了全球极性线索。鼠标皮肤提供了一个理想的系统来识别远距离 极性提示。膨胀的组织上装饰着数千个毛囊（HF），这些毛囊都朝向 通过 PCP 驱动过程实现相同方向。值得注意的是，我们展示了背部皮肤是分开的 进入影响 PCP 信号传导方向的区域。该数据表明，特定区域 远程信号协同协调整个组织中的 PCP 和 HF 方向。为了支持这一点 想法是，小型哺乳动物的自发突变产生了具有独特的、特定区域的破坏的动物 毛囊方向。为了研究这些突变是否影响长程极性基因，我将确定 通过基因组测序确定致病突变并表征突变对组织的影响 使用遗传学和图像分析来确定极性。然后我将询问所识别的蛋白质作为 体内和器官型皮肤培养中的长程极性线索。完成本研究后，我们将确定 并了解在组织过程中协调远距离集体行为的新机制 形态发生。