Nematode gonad development and the evolution of organs

描述(由申请人提供)： 这项研究的长期目标是了解生物是如何在分子水平上进化的。短期目标是了解太平洋线虫的性腺发育。线虫性腺是由体细胞组织和生殖系组织组成的复杂器官。为了形成一个功能器官，必须制造合适的细胞数量，指定合适的细胞类型，并且细胞必须重新排列，以便在正确的位置形成合适大小的功能组织。这些过程中的许多过程在所有生物体中都受到类似的途径和分子的控制，无论是蠕虫还是人类。当这些通路被异常控制时，结果往往是有害的。然而，发育过程必须发生变化，才能产生物种。目前还不知道塑料的基本工艺是怎样的。为了与线虫进行比较，人们已经做了大量的工作，将太平洋隐杆线虫作为第二种遗传模式线虫。对太平洋对虾性腺发育的研究为通过比较研究许多发育过程中的变化提供了机会。太平洋对虾的性腺与线虫的性腺有明显的形态差异。在接下来的三年里，将对太平洋对虾的性腺进行鉴定，并分离与性腺发育有关的基因。将使用经典的谱系技术和激光消融来绘制性腺的命运图。细胞接触将使用电子显微镜进行进一步描述。同时，无偏见的基因筛查将揭示相关的基因座。突变体将根据表型和性腺的特征以及推断的细胞相互作用进行分类。与线虫相比，线虫将开始剖析形成线虫性腺和生殖线的过程发生了怎样的变化。最终，对分子变化模式的洞察可能会发生，并可能导致我们所知的不同的后生动物。

DESCRIPTION (provided by applicant): The long-term objective of this research is to understand how organisms evolve at a molecular level. The short-term goal is to understand gonad development in the nematode Pristionchus pacificus. The nematode gonad is a complex organ composed of both somatic and germline tissues. To form a functional organ, the right number of cells must be made, the right cell-types specified, and ceils must rearrange to form functional tissues of the right size in the correct location. Many of these processes are controlled by similar pathways and molecules in all organisms, whether worm or human. When these pathways are aberrantly controlled, the results are often detrimental. However, changes in developmental processes must occur to allow for the generation of species. It is not known how plastic fundamental processes are. Much effort has established P. pacificus as a second genetic model nematode for comparison with C. elegans. Investigation of gonad development in P. pacificus offers the opportunity to study change in many developmental processes through comparisons. The gonad of P. pacificus has gross morphological differences in comparison to C. elegans. Over the next three years, the P. pacificus gonad will be characterized and genes involved in gonad development will be isolated. Classical lineaging techniques and laser ablations will be used to fate map the gonad. Cell contacts will be further described using electron micrographs. Concurrently, unbiased genetic screens will uncover involved loci. Mutants will be classified by phenotype and according to the characterization of the gonad and inferred cell interactions. Comparison with C. elegans will begin to dissect how the processes that form the nematode gonad and germ line have changed. Ultimately, insights into the pattern of molecular changes that can occur and may have resulted in the varied metazoans we know may be gained.