Rehm E Jay, Hannibal Roberta L, Chaw R Crystal, Vargas-Vila Mario A, Patel Nipam H
Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720-3140, USA.
Cold Spring Harb Protoc. 2009 Jan;2009(1):pdb.emo114. doi: 10.1101/pdb.emo114.
The great diversity of arthropod body plans, together with our detailed understanding of fruit fly development, makes arthropods a premier taxon for examining the evolutionary diversification of developmental patterns and hence the diversity of extant life. Crustaceans, in particular, show a remarkable range of morphologies and provide a useful outgroup to the insects. The amphipod crustacean Parhyale hawaiensis is becoming established as a model organism for developmental studies within the arthropods. In addition to its phylogenetically strategic position, P. hawaiensis has proven to be highly amenable to experimental manipulation, is straightforward to rear in the laboratory, and has large numbers of embryos that are available year-round. A detailed staging system has been developed to characterize P. hawaiensis embryogenesis. Robust protocols exist for the collection and fixation of all embryonic stages, in situ hybridization to study mRNA localization, and immunohistochemistry to study protein localization. Microinjection of blastomeres enables detailed cell-lineage analyses, transient and transgenic introduction of recombinant genetic material, and targeted knockdowns of gene function using either RNA interference (RNAi) or morpholino methods. Directed genome sequencing will generate important data for comparative studies aimed at understanding cis-regulatory evolution. Bacterial artificial chromosome (BAC) clones containing genes of interest to the developmental and evolutionary biology communities are being targeted for sequencing. An expressed sequence tag (EST) database will facilitate discovery of additional developmental genes and should broaden our understanding of the genetic controls of body patterning. A reference genome from the related amphipod crustacean Jassa slatteryi will shortly be available.
节肢动物身体结构的巨大多样性，加上我们对果蝇发育的详细了解，使得节肢动物成为研究发育模式进化多样化以及现存生命多样性的首要类群。特别是甲壳类动物，展现出了显著的形态范围，并为昆虫提供了一个有用的外类群。夏威夷半足类甲壳动物Parhyale hawaiensis正在成为节肢动物发育研究的模式生物。除了其系统发育上的战略地位外，夏威夷Parhyale已被证明非常适合进行实验操作，在实验室中易于饲养，并且全年都有大量胚胎可用。已经开发出一个详细的分期系统来描述夏威夷Parhyale的胚胎发生。对于所有胚胎阶段的收集和固定、用于研究mRNA定位的原位杂交以及用于研究蛋白质定位的免疫组织化学，都有成熟的方案。对卵裂球进行显微注射能够进行详细的细胞谱系分析、重组遗传物质的瞬时和转基因导入，以及使用RNA干扰（RNAi）或吗啉代方法进行基因功能的靶向敲低。定向基因组测序将为旨在理解顺式调控进化的比较研究生成重要数据。含有发育生物学和进化生物学界感兴趣基因的细菌人工染色体（BAC）克隆正被作为测序目标。一个表达序列标签（EST）数据库将有助于发现更多的发育基因，并应拓宽我们对身体模式遗传控制的理解。来自相关半足类甲壳动物Jassa slatteryi的参考基因组不久将可获得。
