ADAM FUNCTION IN NEURAL CREST CELLS

描述(申请人提供)：颅神经脊是一种 在前神经和神经交界处形成的细胞群 脊椎动物胚胎中的非神经性外胚层。这些细胞经历了一种调节的 上皮-间充质转化，从发育中的神经管和 沿着规定的路径在整个头部迁移。数控细胞产生了一种 多种细胞类型和组织，包括软骨和骨骼元素 头部和面部。在诱导、增殖、迁移和/或 细胞分化在颅面神经干细胞分化中的作用 反常现象。因此，对指导计算机控制的分子事件有一个基本的了解 细胞发育和迁移行为是理解病因的关键 头面部缺陷。亚当13岁是亚当斯家族的成员 含有去整合素和金属蛋白酶的跨膜糖蛋白 域。这种蛋白质最初是在非洲爪哇中鉴定出来的，它是 在细胞迁移前和迁移过程中均有表达。亚当13 金属蛋白水解酶的活性被认为在 细胞外基质(ECM)修饰对细胞迁移行为的影响 填充了这些细胞通过的空间。因此，总体来说， 这项研究的目的是确定ADAM 13和其他 在神经脊中表达的亚当家族的成员。一个主要的 目的是建立ADAM 13参与NC迁移的机制。 将使用胚胎转录本注射、转基因方法和转基因技术。 表达ADAM 13野生型和突变型结构以研究ADAM 13在完整的非洲爪哇胚胎、培养的外植体和单细胞中发挥作用。这个 单个ADAM 13结构域的功能特异性(即，金属蛋白酶， 去整合素、富含半胱氨酸和细胞质)也将利用嵌合体进行研究 亚当构造由亚当13的片段和其他结构上相关的片段组成 亚当斯具有不同的生物活性。亚当13胞质尾巴有 已被证明与含有SH3结构域的蛋白质相互作用，这些蛋白质包括Src1和 PACSIN-2。PACSIN-2结合也与ADAM 13的减少有关 体内功能活性。因此，拟议研究的最终目标是 探讨PACSIN-2下调ADAM 13功能的机制。

DESCRIPTION (provided by applicant): The cranial neural crest (CNC) is a population of cells formed at the border between the anterior neural and non-neural ectoderm in vertebrate embryos. These cells undergo a regulated epithelial-mesenchymal transition, emerging from the developing neural tube and migrating throughout the head along defined pathways. CNC cells give rise to a variety of cell types and tissues including the cartilage and skeletal elements of the head and face. Defects in the induction, proliferation, migration and/or differentiation of CNC cells account for a wide range of craniofacial anomalies. Thus, a basic understanding of the molecular events that direct CNC cell development and migratory behavior is critical to understanding the causes of craniofacial defects. ADAM 13 is a member of the ADAMs family of transmembrane glycoproteins, which contain A Disintegrin and A Metalloprotease domain. This protein was identified originally in Xenopus laevis, where it is expressed in CNC cells before and during their migration. ADAM 13 metalloprotease activity is hypothesized to play a critical role in the migratory behaviors of the CNC by modifying the extracellular matrix (ECM) filled spaces through which these cells travel. Therefore, the overall objectives of this study are to establish the functions of ADAM 13 and other members of the ADAM family that are expressed in the neural crest. A primary goal is to establish the mechanism of ADAM 13 involvement in CNC migration. Embryo transcript injection, transgenic methods and transfection will be used to express ADAM 13 wild type and mutant constructs in order to investigate ADAM 13 function in intact Xenopus embryos, cultured explants and single cells. The functional specificities of individual ADAM 13 domains (i.e., metalloprotease, disintegrin, cysteine-rich and cytoplasmic) will also be studied using chimeric ADAM constructs comprised of segments of ADAM 13 and other structurally related ADAMs with differing biological activities. The ADAM 13 cytoplasmic tail has been shown to interact with SH3 domain containing proteins including Src1 and PACSIN-2. PACSIN-2 binding is also associated with a reduction in ADAM 13 functional activity in vivo. Thus, the final aim of the proposed research is to investigate the mechanism by which PACSIN-2 down-regulates ADAM 13 function.