Identification of molecular mechanisms regulating skeletal morphology

脊椎动物骨骼具有多种重要功能，包括形状、力量、灵活性和保护重要器官。建立复杂形式的骨骼需要协调生长与骨形成细胞和关节形成细胞的分化。事实上，关于细胞如何分裂以及相关的细胞类型如何分化，人们已经知道很多。然而，对于这些事件如何协调才能产生正确大小和形状的骨骼元素，人们知之甚少。缝隙连接蛋白Cx43在斑马鱼鳍再生过程中调节细胞增殖和关节形成，表明Cx43同时协调生长和图案形成。为了确定Cx43如何调节这些活动，使用分子遗传学方法确定了可能的靶基因。从这个靶基因列表中验证的依赖于Cx43的基因将被放置在作用于Cx43下游的基因的有序路径中。因此，有可能揭示Cx43在鳍的生长和模式形成过程中调节的步进式分子途径(S)。这一提议的智力价值在于，将揭示建立骨骼形式和图案的机械论洞察力。前50个目标基因的验证将在为本科生开设的一门新的探究式实验室课程中部分完成。因此，这一建议的更广泛影响包括为大量学生提供接触科学实践的机会，同时还提供一套发育生物学的核心实验室技能。这项建议充分融合了智力上的优点和更广泛的影响，既促进了骨骼形态发生知识领域的发展，又提供了如何在实验室环境中解决复杂生物学问题的指导。

The vertebrate skeleton provides a variety of important functions including form, strength, flexibility, and protection of vital organs. Establishment of the complex form of the skeleton requires the coordination of growth with the differentiation of bone-forming cells and joint-forming cells. Indeed, much is known about how cells divide and about how relevant cell types differentiate. However, very little is understood about how these events are coordinated to give rise to skeletal elements of the correct size and shape. The gap junction protein Cx43 has been shown to regulate both cell proliferation and joint formation during zebrafish fin regeneration, revealing that Cx43 coordinates growth and patterning concomitantly. To determine how Cx43 mediates these activities, putative target genes were identified using a molecular genetics approach. Validated Cx43-dependent genes from this list of target genes will be placed in an ordered pathway of genes acting downstream of Cx43. Thus, it will be possible to reveal the step-wise molecular pathway(s) regulated by Cx43 during growth and patterning of the fin. The intellectual merit of this proposal is that mechanistic insights into the establishment of skeletal form and patterning will be revealed. Validation of the top 50 target genes will be completed in part during a new inquiry-based laboratory course for undergraduates. Thus, the broader impacts of this proposal include providing a large number of students access to the practice of science while also providing a set of core laboratory skills in Developmental Biology. The intellectual merit and the broader impacts are fully integrated in this proposal, both advancing the field of knowledge of skeletal morphogenesis and providing instruction on how to solve complex biological problems in a laboratory setting.