权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

DEVELOPMENTAL GENETICS OF ASCIDIANS

海鞘的发育遗传学

基本信息

批准号：
12358012
负责人：
SATOH Noriyuki
金额：
$ 31.42万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2003
项目状态：
已结题

项目摘要

Ascidians provide an appealingly simple experimental system to investigate the function of developmentally relevant genes during chordate development. The ascidian tadpole is composed of only 〜2600 cells, which constitute a small set of larval organs including the epidermis, central nervous system, notochord and tail muscle. This configuration of the tadpole represents the basic chordate body plan. Embryogenesis of the best studied ascidians Ciona intestinalis and Ciona savignyi is rapid (about l8 hr), they are hermaphroditic, self-fertilization is feasible, and the entire life cycle takes less than 3 months, facilitating mutagenesis and genetic screens. The aim of the present study was to introduce forward genetic methods to isolate mutants in these ascidians.We first attempted mutagenesis with chemical mutagens. By treating sperm with the chemical mutagen ENU, several mutant lines were established. For example, chongmague affects notochord formation and zebulon affects head formation … More in Ciona intestinalis embryos.The identification of the affected genes is not simple when mutations are caused by single nucleotide substitutions. A strategy for identifying mutated genes involves insertional mutagenesis with the aid of transposable elements. However, previous attempts at insertional mutagenesis in marine invertebrates were not successful. We found that a Tc1/mariner family transposon Minos, originally isolated from Drosophila hydei, can function as a transposable element in Ciona. The Ciona intestinalis genome is AT-rich and Minos targets TA dinucleotides. This may explain why Minos is active in Ciona embryos. By careful examination of excision, deletion and transposable activity, we have established a number of enhancer trap lines in Ciona intestinalis. This method might represent a significant breakthrough for elucidating gene function in Ciona. At present, we are isolating mutants with deficiencies of adult organ formation.Thus, the present study is the first report of possible insertional mutagenesis in marine animals. Less

海鞘为研究脊索动物发育过程中发育相关基因的功能提供了一个非常简单的实验系统。海鞘蝌蚪仅由约2600个细胞组成，这些细胞构成了包括表皮、中枢神经系统、脊索和尾肌在内的一小套幼虫器官。蝌蚪的这种形态代表了脊索动物的基本身体结构。研究得最好的海鞘Ciona savignyi和Ciona savignyi的胚胎发生是快速的（约18小时），它们是雌雄同体的，自花受精是可行的，并且整个生命周期需要不到3个月，便于诱变和遗传筛选。本研究的目的是引入正向遗传学的方法来分离海鞘的突变体。用化学诱变剂ENU处理精子，建立了几个突变系。例如，Chongmague影响脊索的形成，Zebulon影响头部的形成 ...更多信息在玻璃海鞘胚胎中。当突变由单核苷酸取代引起时，受影响基因的鉴定并不简单。鉴定突变基因的策略包括借助于转座因子的插入诱变。然而，以前在海洋无脊椎动物中插入诱变的尝试并不成功。我们发现，Tc 1/水手家族转座子Minos，最初从果蝇hydei分离，可以作为一个转座因子在玻璃海鞘。玻璃海鞘基因组富含AT，Minos靶向TA二核苷酸。这可以解释为什么Minos在玻璃海鞘胚胎中很活跃。通过对玻璃海鞘增强子的切除、缺失和转座活性的研究，我们建立了一系列增强子捕获系。该方法可能是阐明玻璃海鞘基因功能的一个重大突破。目前，我们正在分离成体器官形成缺陷的突变体，因此，本研究是海洋动物中可能的插入突变的首次报道。少