Axial Patterning in Embryogenesis, Regeneration, and Asexual Reproduction

每一个曾经在地球上行走过的人都是从胚胎发育而来的。然而，许多动物，如海葵，可以通过三种不同的发育途径发育：来自胚胎(胚胎发生)，来自因受伤而支离破碎的成体的一块(再生)，或来自成年自主产生的分支(无性繁殖)。在海葵等动物的基因组中，三种不同的发育途径是如何编码的？为什么像人类这样的动物缺乏这种发育灵活性？这些基本问题的答案将来自于在分子水平上了解胚胎发生、再生和无性繁殖之间的异同。为此，Finnerty实验室将比较特定的轴型基因在海葵胚胎发生、再生和无性繁殖中的作用。轴向图案化是动物的身体沿着其主轴被分成不同区域的过程。例如，相对简单的海葵身体有三个主要区域：头部、中心体柱和脚部。重要的是，轴向图案化是胚胎发生、再生和无性繁殖过程中必须执行的过程。这项研究试图揭示保守的分子机制是否被用来在这些交替的途径中完成轴向模式。将讨论以下具体问题。(1)在每条发育途径中，用于完成轴向模式的基因是否相同？(2)不同发育途径之间基因表达的时间和空间模式是否一致？(3)通过实验手段关闭给定基因对胚胎发育的影响是什么？为了回答问题一和问题二，我们将使用原位杂交和定量RT-PCR技术来检测几个同源盒转录因子的表达。为了回答第三个问题，基因表达将使用RNA干扰技术来“沉默”。

0212773FinertyEvery person that has ever walked the earth developed from an embryo. However, many animals such as sea anemones can develop by three alternate developmental pathways: from an embryo (embryogenesis), from a piece of an adult that has been fragmented by injury (regeneration), or from an autonomously produced offshoot of an adult (asexual reproduction). How are three alternate developmental pathways encoded in the genomes of animals such as sea anemones? Why is this kind of developmental flexibility lacking in animals such as humans? Answers to these fundamental questions will come from understanding the similarities and differences between embryogenesis, regeneration, and asexual reproduction at the molecular level.Towards this end, the Finnerty lab will compare the roles of specific axial patterning genes in sea anemones during embryogenesis, regeneration, and asexual reproduction. Axial patterning is the process whereby an animal's body is divided into distinct regions along its primary axis. For example, the relatively simple body of a sea anemone has three main regions: a head, a central body column, and a foot. Importantly, axial patterning is a process that must be performed during embryogenesis, regeneration, and asexual reproduction. This study seeks to reveal whether conserved molecular mechanisms are used to accomplish axial patterning in these alternate pathways. The following specific questions will be addressed. (1) Are the same genes used to accomplish axial patterning in each developmental pathway? (2) Are the temporal and spatial patterns of gene expression consistent between pathways? (3) What are the consequences for embryogenesis of "turning off" a given gene by experimental means? To address questions one and two, the expression of several homeobox transcription factors will be assayed using the techniques of in situ hybridization and quantitative RT-PCR. To address question three, gene expression will be "silenced" using the technique of RNA interference.