【作者】 杨睿姣；

【导师】 张轩杰；

【作者基本信息】 湖南师范大学 ， 动物学， 2003， 硕士

【摘要】 彭泽鲫(Carassius auratus var pengze)是由江西省水产研究所和九江市水产研究所选育成功的一种优质养殖鱼类，已推广到全国各地养殖。对于其生殖、遗传方式的研究已有一些报道，但分歧很大，未形成一致的观点和结论。本文主要从细胞遗传学等方面分析彭泽鲫的几个重要生物学特征。包括： 1．彭泽鲫染色体数目及倍性的细胞遗传学 采用活体肾细胞直接制片法制备染色体标本。对彭泽鲫肾细胞染色体的数目统计分析表明，彭泽鲫染色体组是由150条基本染色体和若干条小的超数染色体组成。染色体组型按着丝粒位置150条基本染色体可分为四组，每组中同源染色体的组数与已知二倍体鲫鱼的同源染色体组数一致。每个染色体小组均由三条同源染色体组成。在亚端部着丝粒染色体组(st)的第三号染色体组的三条同源染色体的短臂上均有非常明显的随体，可作为彭泽鲫是三倍体的细胞遗传学证据。 对彭泽鲫肌肉样品与对照组二倍体红鲫肌肉样品进行DNA相对含量的检测，彭泽鲫细胞的DNA相对含量是二倍体红鲫细胞DNA相对含量的1.55倍，与染色体实验结果一致。 这些研究结果表明，彭泽鲫是一种三倍体鲫鱼，其染色体数目为3n=150+，核型公式为3n=33m+51sm+33st+33t。 2．彭泽鲫雌核发育的细胞学 采用组织超薄切片法，对彭泽鲫(♀)×彭泽鲫(♂)的受精细胞学观察，彭泽鲫受精后，具有与两性生殖鱼类相同的精子入卵过程和极体排出，但精子入卵后精核始终不解凝，也不与雌性原核融合，是典型的雌核发育鱼类的受精细胞学特征。采用精巢细胞直接制片法对精母细胞减数分裂中期染色体观察表明彭泽鲫精母细胞在进行减数分裂时未发生同源染色体配对，全部为单价体形式，减数分裂中期染色体数目统计结果与彭泽卿肾细胞染色体数目统计结果相同，其精子形成过程中第一次减数分裂异常;对精子与体细胞进行DNA相对含量的检测，精子DNA含量与体细胞DNA含量比为2.218:1，精子DNA含量发生了减半。以上实验结果说明彭泽螂为雌核发育鱼类，其精卵形成过程减数第一次分裂异常。3.彭泽卿与红卿同工酶比较 采用聚丙烯酞胺梯度凝胶垂直电泳法，对雌核发育三倍体彭泽螂和同属的两性生殖二倍体红螂的肝脏、肾脏、肌肉和尾鳍四种组织的乳酸脱氢酶、苹果酸脱氢酶及酷酶进行比较研究。结果如下: 彭泽螂与红螂乳酸脱氢酶同工酶四种组织都共表达17条酶带，但在肌肉组织中彭泽螂比红螂多表达4条酶带，即:LDH一、LDH一2、LDH一3、LDH一4。 彭泽螂与红螂苹果酸脱氢酶同工酶在四种组织中除肌肉组织外，都只有细胞质型苹果酸脱氢酶同工酶的三条酶带表达，即s一MDH一1、s一MDH一2、s一MDH一。肌肉组织中，两种鱼不但有细胞质型苹果酸脱氢酶同工酶的表达，还有线粒体型苹果酸脱氢酶同工酶的表达，且具有多态性。 酷酶同工酶在所检测的10尾彭泽螂和4尾红娜的四种组织各有7条酶带。EST一8只在红鲡肝脏中表达，EST一只在彭泽螂肝脏中表达，但在所检测的10个彭泽螂个体中只有9个个体表达。EST一6在彭泽螂尾鳍的表达明显弱于红螂，只有微弱的表达。 尾鳍EST一6、肝脏EST一2、EST一8及肌肉LDH一1、LDH一2、LDH一3、LDH一4酶带的有无或强弱可作为彭泽螂区别于红卿的特征性酶带。三种同工酶的表达均有明显的组织特异性。在三种同工酶中未发现雌雄差异表达的酶带。未发现与二倍体、三倍体倍性相关的酶带。更多还原

【Abstract】 As a kind of high quality fish, aquatic science research institute in Jiangxi Province and aquatic science research institute in Jiujiang have bred Carassius auturas var pengze. It has been cultivated in nation-wide. There were some reports about its ways of reproduction and heredity, but these results are no in agreement with each other.Several important biological characteristics such as fertilization cytology and hereditary property of Carassius auturas varpengzehad been analyzed in this paper. The results are summarized as follows:1. Cytogenesis of chromosome number and ploidy of carassius auturas var pengzeChromosomes preparation of Carassius auratus var pengze was made from kidney cells in vivo. Statistics analysis of chromosome number of carassius auturas var pengze show the metaphases of which chromosome number is over 150 have some small chromosomes.Analysis of karyotype shows that the 150 basic chromosomes can be divided into four sections according to the position of centromere. The number of homologous chromosome groups in each section is as much as the number of homologous chromosome pairs in diploid species of the Carassius auratus. Each homologous chromosome group has three homologous chromosomes.In subtelocentric chromosome section, all of the three chromosomes of the third homologous chromosome group have satellites at their short arms. Obviously, these three satellite homologous chromosomes can be regarded ascytogenetic characteristic of triploid.DNA relative content of muscle cells of Carassius auratus var pengze and Carassius auratus Far red were measured through flow cytometer. DNA relative content of muscle cells of Carassius auratus var pengze revealed that the ratio of DNA relative content of Carassius auratus var pengze and that of diploid Carassius auratus varred is 1. 55 : 1. It is consistent with the analysis result of chromosome. In those metaphases which the chromosome number is over 150, there is unstable number of little chromosomes that can not be classified into the four sections. Therefore, these little chromosomes can be considered supernumerary chromosomes.These results suggest that carassius auratus var pengze is a triploid Carassius auratus. Chromosome number is 3n=150+. Statistical analysis of chromosome number of kidney cell shows that chromosome set of Carassius auratus var pengze consists of 150 basic chromosomes and 0 to several little supernumerary chromosomes. Karyo formula is 3n=33m+51sm+33st+33t.2. gynogenetic Cytology of carassius auratus var pengzeWith the method of histological section, it was observed that fertilization cytology of Carassius auratus var pengze(♀) × Carassius auratus var pengze ( ♂) . After inseminated, it was observed that a sperm entered egg through micropyle and a polarbody was extruded. But after a sperm entered the egg, spermatozoon nucleus beside female pronucleus was condensed and cannot fuse with female pronucleus. The result shows that Carassius auratus var pengze is gynogenetic reproductive modes. There were no pairs of homologous chromosome in meiosisI metaphase of spermatocyte of Carassius auratus var pengze. It shows the unusual meiosis I during spermatogenesis. Theratio of DNA relative content of tail fin cell and sperm of Carassius auratus var pengze is 2. 218:1, it reveals that DNA relative content of sperm is half of somatic cell. During spermatogenesis, meiosis I is abnormal, this section preliminarily analyzed the mode of the stability of chromosome ploidy of Carassius auratus var pengze and the different mechanism of ogenesis and spermatogenesis in order to better understand the reproductive modes and formation mechanism of triploid of Carassius auratus var pengze.3. Isozyme comparison of carassius auratus var pengze and carassius auturas var redWith the method of vertical polyacrylamide gradient gel electrophoresis (PAGE), to comparison study the lactate dehydrogenase (LDH), malate dehydrogenase (MDH) and esterase (EST) in muscle, kidney, liver and tail fins of gynogenetic c更多还原