MUTATIONS THAT AFFECT NEURAL CELL LINEAGES AND CELL FATES DURING THE DEVELOPMENT OF THE NEMATODE CAENORHABDITIS-ELEGANS
MUTATIONS THAT AFFECT NEURAL CELL LINEAGES AND CELL FATES DURING THE DEVELOPMENT OF THE NEMATODE CAENORHABDITIS-ELEGANS
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DOI：
10.1101/sqb.1983.048.01.050
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发表时间：
1983-01-01
期刊：
影响因子：
--
通讯作者：
ELLIS, HM
中科院分区：
文献类型：
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作者：
HORVITZ, HR;STERNBERG, PW;ELLIS, HM
遗传学提供了一种从分子水平了解神经系统结构、功能和发育的方法。例如，突变动物的分离和表征可以指示特定分子在神经系统中何时何地被利用以及这些分子执行什么功能。更具体地说，由于突变的主要作用是破坏基因的作用，因此对该突变诱导的缺陷的测定可以揭示该基因（以及该基因的RNA或蛋白质产物）发挥功能的时间和位点。原则上，对突变体的检查应该揭示是否存在特定参与特定神经元类型、特定神经元类型集合或一般神经元发育的分子。这些信息应该能说明在发育过程中起作用的分子是如何在神经系统内或在神经和非神经组织内分配的。正如Brenner（1973）所指出的，一种适合于神经系统遗传分析的生物体是秀丽隐杆线虫。这种线虫很小（成虫约1毫米长），由很少的细胞组成。例如，成年C.秀丽线虫雌雄同体包含302个神经元（白色等人，这卷），其中只有8个是多巴胺能的（Sulston et al. 1975），只有2个是多巴胺能的（Horvitz et al. 1982 b）。这302个神经元的数量、位置和形态在个体之间基本上是不变的，因此C. elegans可以被认为是一个"被识别的神经元"。"此外，C.已从连续切片的电子显微照片建立了线虫神经系统（Albertson和Thomson 1976;白色等1976和本卷; Sulston等1980）。C. elegans简单、不变和已知的特性为详细确定突变动物的细胞缺陷提供了重要依据。C.秀丽隐杆线虫非常适合于遗传研究（Brenner 1974;赫尔曼和Horvitz 1980）。其快速的世代时间（从受孕到成熟3天），大量的后代（每个亲本300个）和小尺寸有利于大量动物的生产和处理;这些特征使得能够分离出详细遗传分析所需的罕见突变体或重组个体。因为C.秀丽线虫通常以内部自我繁殖的方式繁殖，
Genetics provides one approach toward a molecular understanding of the structure, functioning, and development of the nervous system. For example, the isolation and characterization of mutant animals can indicate when and where particular molecules are utilized in the nervous system as well as what functions those molecules perform. More specifically, since the primary effect of a mutation is to disrupt the action of a gene, the determination of the defect (s) induced by that mutation can reveal the time (s) and site (s) at which that gene--and thus, in general, the RNA or protein product of that gene--functions. In principle, an examination of mutants should reveal whether there are molecules that are specifically involved in the development of particular neuron types, of particular sets of neuron types, or of neurons in general. Such information should indicate how molecules that function during development are partitioned either within the nervous system or within both nervous and nonnervous tissue. As pointed out by Brenner (1973), one organism appropriate for a genetic analysis of the nervous system is the nematode Caenorhabditis elegans. This nematode is small (adults are about 1 mm long) and consists of few cells. For example, the nervous system of the adult C. elegans hermaphrodite contains 302 neurons (White et al., this volume), of which just 8 are dopaminergic (Sulston et al. 1975) and only 2 are serotonergic Horvitz et al. 1982b). The number, positions, and morphologies of these 302 neurons are essentially invariant among individuals, so that every neuron in C. elegans can be considered to be an" identified neuron." In addition, the complete circuitry of the C. elegans nervous system has been established from electron micrographs of serial sections (Albertson and Thomson 1976; White et al. 1976 and this volume; Sulston et al. 1980). That the neuroanatomy of C. elegans is simple, invariant, and known provides an important basis for the detailed determination of the cellular defects of mutant animals. C. elegans is well suited for genetic research (Brenner 1974; Herman and Horvitz 1980). Its rapid generation time (3 days from conception to maturity), large number of progeny (300 per parent), and small size facilitate the production and handling of large numbers of animals; these features enable the isolation of the rare mutant or recombinant individuals needed for detailed genetic analyses. Because C. elegans generally reproduces as an internally self-fertilizing hermaphro-