Developmental and evolutionary skeletal biology

作为一名发育生物学家，我研究鱼类和青蛙胚胎的骨骼是如何形成的。我应该说是骨骼，因为所有脊椎动物都有两个骨骼已经有近5亿年的历史了。你在博物馆里看到的大多数人类或恐龙骨骼都是内骨架，它是基于软骨的，其中大部分被骨头取代。你的手臂骨骼是内骨骼的一部分。第二具骨骼原本在外面，所以是外骨骼。最初，它由骨头和牙本质（牙齿中的组织）组成，要么是小的独立板，要么是融合成外部盔甲的板。在进化过程中，一些板块下沉成为牙齿，并形成锁骨（锁骨）和部分头骨。这两种骨骼有着不同的发育和进化历史。目前，我们正在研究青蛙和鱼类的骨骼发育。青蛙很迷人，因为蝌蚪的骨骼是基于软骨的，而成年青蛙的骨骼是基于骨头的。我们想知道有多少蝌蚪头骨骨骼会遗传给成年青蛙。如果没有延续下去，那么成年骨骼元素是从一组不同于蝌蚪软骨骨骼的细胞中产生的吗？我们在绿色荧光蛋白（GFP）上插入软骨或骨骼的特异性基因，并将其注入青蛙卵中。由此产生的卵有绿色的软骨或骨骼。如果这种结构被结合到制造卵子和精子的细胞中，那么下一代的骨骼也会发出绿色的光。通过使用不同的基因结构，我们可以追踪在青蛙一生中不同时期形成不同骨骼组织的细胞。我们知道青蛙的骨骼组织是软骨和骨头。鱼类的情况就不那么明确了，它们在软骨和骨骼之间发生转变。因此，我们的鱼类研究旨在确定鱼类（大西洋鲑鱼和斑马鱼）中存在的骨骼组织类型以及组织之间可能的转换。然后我们可以使用基因-绿色荧光蛋白探针来揭示形成这些组织的不同细胞群。由于骨骼畸形，孵化场多达30%的鱼无法进入市场。因此，本研究对水产养殖业和经济具有潜在的意义。

As a developmental biologist, I study how the skeleton of embryos of fish and frogs form. I should really say skeletons because all vertebrates have had two skeletons for almost 500 million years. Most of the human or dinosaur bones you see in a museum are the inside (endo) skeleton, which is based on cartilage, most of which is replaced by bone. Your arm skeleton is part of the endoskeleton. The second skeleton was originally on the outside and so is an exoskeleton. Originally it consisted of bone and dentine (the tissue found in teeth), either as small isolated plates or as plates fused into an external armor. During evolution, some plates sank in as teeth and to form the clavicle (collar bone) and parts of the skull. These two skeletons have distinct developmental and evolutionary histories. Currently, we are investigating skeletal development in frogs and fish. Frogs are fascinating because the tadpole skeleton is based in cartilage but the adult skeleton is based on bone. We want to know how much of the tadpole skull skeleton is carried over to adult frogs. If not carried over then do adult skeletal elements arise from a line of cells distinct from those that form the tadpole cartilaginous skeleton? We tack genes that specific for cartilage or bone onto green fluorescent protein (GFP) and inject the construct into frog eggs. The resulting eggs have green cartilages or bones. If the construct is incorporated into cells that make eggs and sperm, then the skeleton of the next generation will also glow green. By using different gene constructs we can track cells making different skeletal tissues at different times during the frog's lifetime. We know the skeletal tissues in frogs - they are cartilage and bone. The situation is much less clear-cut in fish, in which transitions between cartilage and bone occur. So, our fish study is aimed as identifying the types of skeletal tissues present in fish (Atlantic salmon and zebrafish) and the possible transitions between tissues. Then we can use gene-GFP probes to reveal the different cell populations that make these tissues. As much as 30% of fish in hatcheries never make it to market because of skeletal deformities. Therefore, this research has potential significance for the aquaculture industry and for the economy.