中国科学院昆明动物研究所机构知识库

蒲氏黏盲鳗（学名：Eptatretus burgeri）是盲鳗科科盲鳗属属的一种，与七鳃鳗同属于圆口纲，是现存的最古老的脊椎动物。盲鳗作为最古老的脊椎动物，进化地位十分特殊，对于解释早期脊椎动物全基因组复制事件，早期脊椎动物的进化及体细胞重排事件（除生殖细胞外，体细胞会发生遗传信息的丢失）有重要的意义。针对盲鳗体细胞广泛存在的重排现象，我们选取了精巢DNA作为测序的来源，避开了体细胞的重排，并选取了另一个个体的脑，心，肝，肠，肾，肌肉，精巢，鳃和血共9个组织的DNA用于测序。找到了不同组织在体细胞重排过程中缺失的序列，对这部分序列进行了注释分析。最终发现，盲鳗体内存在的体细胞重排，发生缺失的序列主要是散在重复序列。对于发生重排的重要基因研究发现，这部分基因主要涉及癌症发生，早期发育及生殖有利的基因。这个结果暗示，体细胞重排过程清除了一部分对体细胞发育和功能无关的基因，即“体细胞无用基因”。进化分析方面，完成了系统发育树，正选择基因及快速进化基因分析，基因家族扩张收缩，结合已发表脊椎动物代表性物种基因组及转录组数据，脊索动物及棘皮动物基因组及转录组数据，找到脊椎动物大脑起源关键性基因及脊椎动物首次出现的基因。这部分基因功能主要集中在神经，脑的功能，运动相关及能量代谢方面。暗示着脊椎动物早期进化过程中，神经系统的发育及相关功能有一个巨大的变化，与无脊椎动物相比，脑及神经功能有一个质的变化。这一系列研究，有望理清脊椎动物早期进化模式及体细胞重排的格局，为后续的研究奠定了基础。此外，该论文探讨了景东翅子树（学名：Pterospermum kingtungense）的生物学特性。景东翅子树属于梧桐科翅子树属，是云南省滇中地区石灰岩山地常绿阔叶林中的特有树种，是大径级用才树木，属于国家二级重点保护野生植物，濒危等级属极危。通过转录组数据的深入挖掘，并与已发表组学数据的最近缘的可可进行比较基因组学的分析，找到了景东翅子树快速生长及石灰岩土质适应性的相关基因。为景东翅子树这一云南特有种的研究提供了第一个组学数据，为后续的研究及濒危物种的保护提供了组学基因。

The inshore hagfish (Eptatretus burgeri) is a species of Myxinidae, which is one of the oldest vertebrates in existence. As the oldese verbebrates, the genome of hagfish have great significance in explaining the whole genome duplication events of vertebrates, the evolution of early vertebrates and the genome rearrangement. In order to avoid the genome rearrangement of hagfish and obtain the complete genome sequences, we choose testis DNA for genome sequencing and we also choosed 9 different tissues (brain, heart, liver, intestines, kidneys, muscles, sperms, gills and blood) of another invidual for DNA extraction and sequencing. Using reads coverage information, all these tissues missing sequences were identified and annotated. At last, we found that most of the missing sequence are tandem repeat. Some of the genes in testis genome do lost in somatic genome, and these genes are related about cance, early developmental stage and reproduction benefical genes. These results indicate that the genome rearrangement removed some unrelated gene of somatic cells development, we called these genes “useless genes for somatic cell”. What’s more, the positive selected genes and first evoluted genes of vertebrates were found. These first evoluted genes are related about the neural development, brain, motility and Energy Metabolism. These results indicate that with the early evolution of vertebrates, the neural system have made great progress. All these results have laid a foundation for further study of hagfish and the meaning of genome rearrgenment.In addition, this thesis also discussed the biological characteristics of Pterospermum kingtungense. Pterospermum kingtungense is a species of Sterculiaceae. Pterospermum kingtungense, belonging to Sterculiaceae, Malvales, is endemic to subtropical evergreen broad-leaved forest on Limestone Mountain of central Yunnan. This species is distributed in the Jingdong County, one of the biodiversity hotspots of CI. By analysis of the transcriptome data and global comparison of homology between P. kingtungense and cacao, we found the possible mechanism on its characteristics on the limestone adaption and excellent wood properties, which will be important for its conservation and sustainable utilization.