猕猴白化病分子机制和灵长类的分子进化研究

	猕猴白化病分子机制和灵长类的分子进化研究
	丁波
学位类型	博士
导师	张亚平
	1998-07
学位授予单位	中国科学院研究生院
学位授予地点	北京
关键词	灵长类猕猴（macaca Mulatta) 白化病酪氨酸酶基因分子进化系统发育线粒体dna 控制区遗传多样性
摘要	酪氨酸酶是黑色素合成当中的关键酶。人酪氨酸酶基因包括5个外显子，在染色体11q14-q21位置上占据了约50kb长的区域。对人类眼皮肤型白化病（Oculocutaneous albinism, OCA)的许多研究表明，该病主要是由于酪氨酸酶基因的突变引起的。昆明动物研究所白化猴研究小组数十年来一直从事白化猕猴的培育和研究工作，目前饲养着2只白化猕猴和它们的后代，这提供了我们研究猕猴白化分子机制目的条件。为了弄清猕猴白化病的分子机制，我们根据人酪氨酸酶基因序列设计了5对PCR引物扩增相应的5个外显子，序列分析表明，白化猕猴珍珍酪氨酸酶基因第184个密码子第2位置（外显子1的核苷酸位置551）处发生一个C→A的无义突变，使编码丝氨酸（Ser)的密码子变成了一个终止密码，这样后面1038bp的核苷酸片段（346个氨基酸残基）被截断，导致酪氨酸酶翻译不完全，迄今为止，并没有发现合成黑色素的第二条生化途径，因此由于该酶不能行使正常功能而将导致黑色素不能正常表达。这可能是导致该例猕猴白化病的原因。为了解酪氨酸酶基因序列变异的规律及其与功能的关系，探讨该基因作为系统发育研究中遗传标记的有效性，我们测定了黑猩猩（Pan troglodytes)、倭黑猩猩（Pan paniscus)、大猩猩（Gorilla gorilla)、猩猩(Pongo pygmaeus)、长臂猿（Hylobates lar)、食蟹猴（Macaca fascicularis)、狒狒（Simia cynocephalus)、猕猴（Macaca mulatta)、熊猴（Macaca assamensis)、菲氏叶猴（Presbytis p. crepusculus)、白臀叶猴（Pygathrix nemaeus)、滇金丝猴（Rhinopithecus r. bieti）和蛛猴（Ateles paniscus)13个灵长类中代表种的酪氨酸酶基因全部5个外显子的DNA序列。基于这些序列，用简约法构建了分子系统树。结果表明，人猿超科与旧大陆猴各自形成一单系群。人猿超科各物种和旧大陆猴有明显分化，人与大猩猩的关系比人与黑猩猩的关系近。酪氨酸酶基因在解决灵长类系统发育关系上是一个较有用的基因。为了进一步了解中国猕猴（Macaca mulatta)的亚种分化和不同地理群体间的基因流状况，我们测定了来自中云南、广西、福建、海南、浙江、河南、湖南、湖北、安徽、四川、贵州和越南猕猴共96只个体和一只外群食蟹猴的线粒体DNA控制区576bp的DNA序列，基于这些序列，运用距离法对中国恒河猴的分子进行和遗传多样性进行了分析，我们的研究结果显示，云南、四川和湖南猕猴群体与其它群体存在显著分析，海南群体内遗传多样性最低、四川、广西、浙江、福建和越南群体内遗传多样性较丰富。中国猕猴的分化可能存在三条路线。中国猕猴的遗传多样性较丰富。
其他摘要	Tyrosinase is the essential enzyme in melanogenesis. The human tyrosinase gene contains five exons and spans more than 50 kb of DNA on chromosome segment 11q14-q21. Studies on human Oculocutaneous albinism (OCA) show that the tyrosinase gene mutation results in OCA. Albino rhesus monkey research group of Kunming Institute of Zoology has bred the albino rhesus monkeys for more than ten years. Two albino monkeys and their off spring are now bred. These animals supply research samples for molecular basis study. To identify the molecular basis of the albinism, we designed five pair PCR primers according to the human tyrosinase gene and amplified the five exons of tyrosinase gene. Sequence analysis show that a nonsense mutation, from C to A, at the second position of codon 184 which truncates a 1038 bp nucleotide (346 amino acids). This nonsense mutation results in a pre-stop when the gene is translated. So the melanin could not be synthesized properly due to the inactivity of tyrosinase. We infer that the nonsense mutation might be the cause for albinism of rhesus monkey. The mutation of tyrosinase gene leads to albinism. We sequenced the DNA sequences of five exons of tyrosinase gene from chimpanzee, pygmy chimpanzee, langur, Phayre's langur, Assam macaque, and yunnan golden monkey. A phylogenetic trees was constructed using parsimony method. The tree show that Hominoid and Old World Monkeys are monophyletic. A distinguished divergence occurred between Hominoid and Old World Monkeys. Human is closed related to gorilla more than to chimpanzee. In the Old World Monkey clade, Yunnan golden monkey, Douc langur, and Phayre's langur are divided into a monophyletic group. Baboon, rhesus monkey, crab-eating monkey and Assam macaque are divided into another monophletic group. Our results suggest that the tyrosinase gene is a suitable marker for resolving the phylogeny of primates. We sequenced the 576bp of control region of mtDNA in 97 rhesus monkeys(Macaca mulatta) from Yunnan, Guangxi, Fujian, Hainan, Zhejiang, Henan, Hunan, Hubei, Anhui, Guizhou and Vietnam populations and a crab-eating monkey. A UPGMA tree was constructed Based on the sequences. Our results show that there are remarkable genetic differentiations between Yunnan, Sichuan and Hunan and the other populations. The genetic diversity in Hainan population is the lowest and in Sichuan, Zhejiang, Fujian and Vietnam populations are high. Three lines can be explained as the radiation of Chinese rhesus monkeys. The genetic diversity in Chinese rhesus monkeys is high.
语种	中文
文献类型	学位论文
条目标识符	http://ir.kiz.ac.cn/handle/152453/6200
专题	科研部门_分子进化与基因组多样性（张亚平）
推荐引用方式 GB/T 7714	丁波. 猕猴白化病分子机制和灵长类的分子进化研究[D]. 北京. 中国科学院研究生院,1998.

条目包含的文件
文件名称/大小	文献类型	版本类型	开放类型	使用许可
1998008.pdf（2251KB）	学位论文		开放获取	CC BY-NC-SA	请求全文