| 低氮培养与渗透胁迫下发菜的生长及转录组学研究 |
| Alternative Title | Growth and transcriptomic study of Nostoc flagelliforme under low-nitrogen cultivation and osmotic stress
|
| 薄乐涛 |
| Thesis Advisor | 安黎哲
|
| 2016-05-22
|
| Degree Grantor | 兰州大学
|
| Place of Conferral | 兰州
|
| Degree Name | 硕士
|
| Keyword | 发菜
低氮培养
渗透胁迫
转录组
|
| Abstract | 本研究通过对液体培养的发菜在15d低氮培养以及24h渗透胁迫处理下的超微结构观察、生理响应以及转录组表达情况进行研究，阐述发菜在恶劣环境下的生存及抗逆机制。获得如下结果：
1) 液体培养发菜经15d低氮培养以及24h 15%聚乙二醇(PEG)渗透胁迫处理后，在电镜下发菜的藻体、繁殖细胞和营养细胞的亚细胞结构未发现明显的变化。
2) 低氮培养可能会抑制发菜的光合作用，破坏细胞膜的完整性，打破发菜体内氧化还原平衡，并启动发菜的超氧化物酶的抗氧化能力。渗透胁迫会造成发菜细胞失水，还可能会抑制发菜的光合作用，破坏细胞膜的完整性和蛋白质结构，打破发菜体内氧化还原平衡，并启动发菜的超氧化物酶的抗氧化能力。
3)对发菜的全基因组扫描测序，得到发菜基因组大小8,756,642 bp，GC含量41.5%，检测到的基因数目为9131个，平均读长965 bp。
4)对发菜的转录组学进行分析。发现在15d低氮培养后，很多参与氮代谢的基因表达量显著上调，但是很多参与调控光合作用的基因表达量则显著下调。在渗透胁迫下，很多参与氮代谢、RNA降解和硫代谢途径的基因表达量均显著上调，而参与淀粉和蔗糖代谢、半乳糖代谢以及脂肪酸代谢的很多基因表达量则显著下调。 |
| Other Abstract | In this study, aquatic-living N. flagelliforme in response to 15 days low-nitrogen cultivation and 24h osmotic stress was researched in different levels through ultrastructural observation, physiological test and high-throughput sequencing. The results are as follows:
1) After 15 days low-nitrogen cultivation and 24h osmotic stress, the structure of filaments, division cells and vegetative cells remained unchanged under observation of transmission electron microcopy (TEM).
2) Low-nitrogen cultivation might inhibit the effects of photosynthesis, damage to cell membrane integrity and break the osmotic balance, increase the level of celluar redox and oxygen free radicals. Osmotic stress would cause loss of cell water and inhibit the effects of photosynthesis, cause damage to protein structure damage to cell membrane integrity and break the osmotic balance, increase the level of celluar redox and oxygen free radicals.
3) A high-quality genome scanning database of N.flagelliforme was constructed successfully. A 8,756,642 bp genome with 41.5% GC content were obtained after de novo assembly. 9,131 Unigenes with average length of 965bp were obtained, and the length of 44,908 pieces(44.39%) is more than 500bp.
4) We sequenced transcriptome of N.flagelliforme by using the Illumina high-throughput transcriptome sequencing technique. After 15 days low-nitrogen cultivation, many genes involved nitrogen metabolism were significantly up-regulated in response to low-nitrogen condition, however, genes involved in photosynthesis were significantly down-regulated. Many genes involved nitrogen metabolism, RNA degradation and sulfur metabolism were significantly up-regulated in response to osmotic stress, however, genes involved in starch and sucrose metabolism, galactose metabolism and fatty acid metabolism were significantly down-regulated. |
| URL | 查看原文
|
| Language | 中文
|
| Document Type | 学位论文
|
| Identifier | https://ir.lzu.edu.cn/handle/262010/221565
|
| Collection | 生命科学学院
|
Recommended Citation
GB/T 7714 |
薄乐涛. 低氮培养与渗透胁迫下发菜的生长及转录组学研究[D]. 兰州. 兰州大学,2016.
|
Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.
