番茄近缘种核型比较分析
毕业论文关键词：番茄；FISH；rDNA；核型分析
Karyotype Comparative Analysis of rDNA Distribution in Metaphase Chromosomes of Tamato Species
Abstract: Tomato genome size is about 950Mb, and there is a rich relatives germplasm in solanaceae plants. The karyotype analyses about the wild tomatoes and its relatives germplasm were finished employing dual-color FISH technology with two BAC clones probes to located on the mitotic metaphase chromosomes. Fistly, when 45SrDNA from tomatoes pTa71 clone was used as probes in the FISH experiments, the result show that there is strong hybridization signal only in the satellite body to the end of the acrocentric chromosome, and only the chromosome satellite contains the coding regions encoding 45SrDNA in plants of solanaceae and its relatives germplasm, and there are a pair of 45S rDNA loci in tomato, and the results show, too, that the satellite is easy to fracture. Secondly, when another probe, the 5S rDNA from pCT4.2 of tomato, was used in FISH, it was found that the sites, only in Nucleolus Organizer Region with the strong signal, doubles. In this study, the conservative and evolution trend of genomes of tomatoes and its relatives is discussed based on karyotype analysis from 45S rDNA&5S rDNA-FISH.
Key words: Tomato; FISH; rDNA; karyotype analysis
目 录
摘 要 1
关键词 1
Abstract. 1
引言 2
2. 材料和方法 3
2.1 实验材料 3
2.1.1 材料 3
2.1.2 供试质粒探针 3
2.1.4 仪器设备 3
2.2 实验方法 3
2.2.2 染色体分裂相滴片 4
2.2.3 基因组DNA提取及探针标记 4
2.2.4 荧光原位杂交 4
2.2.5 信号检测及分析 5
3. 结果与分析 5
3.1 45S和5S rDNA BAC克隆质粒的提取及探针切刻平移标记 5
3.2 45S和5S rDNA在有丝分裂中期染色体上的原位杂交结果 6
4.讨论 8
参考文献 10
致谢 12
番茄近缘种核型分析
引言
番茄是是人们日常饮食和生活中必不可少的一种果菜，具有丰富的营养价值和药理功能。有关番茄的研究显示我国番茄栽培历史较短，而且所有的品种资源都来自国外。目前，我国已成为番茄的主要生产国之一，番茄在我国各地广泛种植，栽培面积仍在进一步扩大。在种植的过程中，经过不断的有目的人工定向选择和自然不定向的选择，形成了许多具有各种特色的品种，丰富和满足着我们餐桌文化。番茄在植物学分类上，属茄科(Solanaceae)、番茄属(Lycopersicon)，除栽培种之外，还有很多近缘野生种，具有极其丰富的遗传资源。利用FISH技术[1]，通过对番茄近缘野生种的染色体上DNA序列[2]定位分析来研究番茄及其近缘种之间的进化关系，有利于近缘种丰富的基因资源的利用，是今后研究的一个重要领域，目前在国内尚未见报道。本研究试图利用FISH技术对其染色体进行细胞遗传学核型比较分析，以期揭示它们的进化关系，推动其在传统和分子育种工作中的应用。