模式动物 z-bo 2020-07-28 843

　　The classification of all model organisms is very different, but they also have some common characteristics. First, these organisms are highly adaptable, easy to feed, fertile, and easy to obtain large amounts of test substances. Secondly, these biological environments and human health will not cause too much harm, nor will it harm the experimenters and the experimental ecological environment.

　　2.1 The special advantages of Caenorhabditis elegans under natural conditions. Nematodes are the entire body of males and females. They can produce about 300 fertilized eggs in their lifetime and reproduce rapidly. At the same time, under natural or induced conditions, male individuals can be produced for hybridization experiments. This feature gives C. elegans an unparalleled advantage in genetic research. In addition, C. Among all 1090 cells in the nematode, 131 cells disappeared at a fixed time and location in a fixed manner. The specific number of C. elegans cells and fixed cell apoptosis are the main reasons for determining the status of C. elegans in apoptosis studies (QinFS, 2006).

　　2.2 Special advantages of fruit flies

　　The advantages of Drosophila as a model organism are mainly reflected in two aspects: biology and technology. Biologically speaking, long-term research in fruit flies has accumulated a lot of knowledge and information, and a large number of mutants distributed in thousands of genes have been prepared. Drosophila also has many characteristic chromosomes with phenotype, molecular or other markers, which can facilitate genetic manipulation. These tools can be used to isolate a set of visible or fatal phenotypes in large-scale genome screening. A phenotype that appears only in the second or third generation. Technically speaking, some effective technologies developed in the research process of Drosophila are only applicable to Drosophila: enhancer capture technology, site-specific homologous recombination technology, two-component gene expression system in different places, mosaic analysis technology and gene specificity Sex knockout technology (AdamsMD, 2002).

　　2.3 Special benefits of zebrafish

　　The zebrafish can be a model organism and has its own unique advantages. Biologically speaking, in vitro fertilization of zebrafish, embryos occur in vitro, are transparent and easy to observe and manipulate. The diameter of the fertilized egg is about 1mm, which is convenient for microinjection and cell transplantation. Technically, zebrafish can perform cell labeling and cell lineage tracking, such as Caenorhabditis elegans and Drosophila, and embryonic cell transplantation, such as Xenopus laevis. At the genetic level, transgenic technology, gene overexpression technology and random targeted gene-specific mutagenesis technology have been developed (SunZH, 2006).

　　2.4 unique advantages of mice

　　Mice are mammals and are closely related to humans. This is their main advantage as a model organism for medical research. At the same time, mice will form vaginal plugs during mating. This can determine the mating time well. This is very important for determining the development time of the research. In terms of technology, long-term experimental research has trained a large number of experimental personnel and established a wide range of experimental systems, such as gene traps, chemical mutagenesis and gene-specific mutations (LinZY, 2006).