双滴虫与细胞核起源问题的探索
文献类型：期刊论文
| 作者 | 李靖炎 |
| 刊名 | 动物学研究
 |
| 出版日期 | 1996 |
| 卷号 | 17期号:3页码:275-286 |
| 关键词 | 双滴虫类 蓝氏贾第虫 细胞核的起源 原始性细胞核 |
| ISSN号 | 0254-5853 |
| 其他题名 | Diplomonads and The Exploration on The Origin of Cell Nucleus |
| 中文摘要 | 分析了可能用作研究原始性细胞核的模型的涡鞭毛虫与双滴虫核，发现实际上只有后者是适用的。以蓝氏贾第虫（Ｇｉａｒｉｄｉａｌａｍｂｌｉａ）作为双滴虫类的代表，对其核作了多方面的考察，发现其核中确实还没有核仁；核被膜上有天然的缺口；但核内已经有了核骨架及５种组蛋白。比较的免疫印迹检查表明，在检查到的各种原生生物中，蓝氏贾第虫的着丝粒／动粒蛋白最接近于原细菌的相应蛋白。有人怀疑蓝氏贾第虫缺少线粒体及典型高尔基氏器等原始性特征实际上不过是由于过寄生生活所致。本文针对这种怀疑进行了多方面的分析。其实所有过自由生活的双滴虫类都没有线粒体及典型高尔基氏器，看来也全都没有核仁，核被膜全都有缺口。依据上述的发现，对真核细胞发生之初原始性细胞核的特性进行了推断，进而对细胞核的整个起源过程进行了分析：认为在真核细胞的原细菌祖先体内就已经有了核骨架；多个类核体的ＤＮＡ结合在其上而构成了核区。我们关于组蛋白的分子进化研究表明，核小体组蛋白的共同祖先在极早的时候就已经分化成了４种。因此可以相信，真核细胞的原细菌祖先很早就有了４种核小体组蛋白和核小体。本文着重分析了染色体的起源过程并进一步发展了过去已经提出的核被膜起源于原始性内质网的学说. |
| 英文摘要 | The nucleus of dinoflagellates had been used as the model of the primitive nucleus.However,this model was found unsuitable.According to this model the chromosomal basic protein of dinoflagellates should represent a very primitive nucleosomal histone-related protein and the differentiation of four nucleosomal histones should take place after the emergence of the primitive nucleus.But both two deductions were found to be incorrect.In other respect,various studies of molecular evloution studies showed dinoflagellates were not the most primitive ones among present-existing eukaryotes,but might only be the primitive ones among matakaryotes.Superkingdom Archezoa seems to be the primitive eukaryotes,which possess no mitochondria,no typical Golgi apparatus,and no 80S type of ribosomes,but have 70S type of ribosomes just as prokaryotes have.According to the studies of molecular evolution of large rRNAs and 5.8S rRNA,diplomonads,in turn,seem to be the most primitive ones among the present-existing Archezoa,therefore,their nucleus might perhaps be the suitable model of the primitive cell nucleus.Giardia lamblia was used as the representative of diplomonads and the nucleus of its trophozoite was studied in our laboratory in recent years,The following points were found:1.No nucleolus was found with various detection methods.2.The nuclear enevelope of Giardia was found incomplete for the first time.Large openings were seen in its nuclear envelope.The natural existence of the nuclear envelope openings has been confirmed by sequential ultrathin sectiontions.3.Nuclear matrix was already found in its nucleus.4.The nuclear.lamina seems very primitive because only lamin B was found it and it could not bear routine sequential specific extractions for demonstrating nuclear lamina and nuclear matrix.5.The centromere protein B and kinetochore porteins of Giardia were found mostly simlar to the corresponding proteins in various archaebacteria.6.Giardia nucleus was found already having five species of histones.7.Our preliminary observations showed that spindle and spindle microtubules have not been found within the dividing nucleus of Giardia.The possibility that the above described special characteristics were produced only due to the parasitic life of Giardia,was analyzed and refuted.ln literature,nucleolus was never found in several other genera of diplomonads,and in other genera heterochromatin structures were mistaken for nucleolus.According to the electron-microscopical photographs in literatue we found that nuclear envelope openings not only existed in Giardia,but also existed in other diplomonads,whether parasitic or free-living.The discovery of nuclear evelope openings in diplomonads confirmed our hypothesis on the origin of nuclear envelope from the primitvie endoplasmic reticulum in the prokaryotic acestor of eukaryotic cells (Li jing-yan,1979).In the light of the nucleus of diplomonads,we presumed that the primitive nucleus in evloutionary history should have nuclear matrix,nucleosomes,from species of nucleosomal histones and typical eukaryotic chromatin already,but still have no nucleolus and its nuclear envelope should be incomplete.Furthermore,we analyzed the facts concerned and proposed an inference about the archaebacterial ancestor of eukaryotic cells.The whole process of the evloutionary formation of cell nucleus was investigated,especially the formation of eukaryotic chromatin.The significance of the emergence of nuclear matrix in the formation of eukaryotic chromatin was emphasized.At the same time our hypothesis on the origin of nuclear envelope was also further developed. |
| 收录类别 | 其他 |
| 资助信息 | 国家自然科学基金 |
| 原文出处 | 1996173275.pdf |
| 语种 | 中文 |
| 公开日期 | 2010-08-24 |
| 源URL | [http://159.226.149.42:8088/handle/152453/3445]  |
| 专题 | 昆明动物研究所_其他 昆明动物研究所_细胞与分子进化开放实验室 |
| 作者单位 | 中国科学院昆明动物研究所细胞与分子进化开放研究实验室,昆明650223 |
| 推荐引用方式 GB/T 7714 | 李靖炎. 双滴虫与细胞核起源问题的探索[J]. 动物学研究,1996,17(3):275-286. |
| APA | 李靖炎.(1996).双滴虫与细胞核起源问题的探索.动物学研究,17(3),275-286. |
| MLA | 李靖炎."双滴虫与细胞核起源问题的探索".动物学研究 17.3(1996):275-286. |
入库方式： OAI收割
来源：昆明动物研究所
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