无核仁原生动物蓝氏贾第虫rDNA的分布  

Distribution of rDNA in the Nucleus of Giardia lamblia: Detection by Ag\|Ⅰ Silver Stain

作　　者：陈泳宏[1] 郭建[2] 李靖炎[3] 刘平[1] 张留宝[1] 

机构地区：[1]第二军医大学南京军医学院组胚教研室,南京210099 [2]南京林业大学环境学院动物学教研室,南京210037 [3]中国科学院昆明动物研究所细胞与分子进化开放实验室,昆明650223

出　　处：《动物学杂志》2002年第5期2-5,共4页Chinese Journal of Zoology

基　　金：国家自然科学基金资助项目 (No .3 93 70 3 4 5 )

摘　　要：过去的工作已表明 ,源真核生物 (Archezoa)中的双滴虫类极其原始 ,核中尚无核仁发生 ,以蓝氏贾第虫 (Giardialamblia)作为双滴虫类的代表 ,用高度特异的核仁组织区银染法 (改良的Ag Ⅰ法 ,李靖炎 ,1985 )在电镜下检视其rDNA在核中的分布。结果发现 ,代表rDNA之所在的银粒并不集中形成任何类似核仁组织区或核仁纤维区的结构 ;在作为对照的小眼虫 (Euglenagracilis)体内 ,银粒则完全集中在核仁纤维区中 ,因此 。Previous investigations have already proved that diplomonads are very primitive in their cell nucleolus, nucleolus had not emerged. We detected the distribution of rDNA in diplomonad nuclei that lacked a nucleolus. Giardia lamblia was used as the experimental animal with Euglena gracillis as the control. The distribution was demonstrated indirectly by the modified Ag\|Ⅰ silver technique (Jingyan Li, 1985)which can specifically indicate the nucleolus organizing region (NOR) under both light and electron\|microscopes.\;In the ultrathin section of the silver stained Euglena cells, all the silver grains concentrated in the fibrosa of the nucleolus, while no silver grains were found in the cytoplasm, nucleoplasm, condensed chromosomes or the pars granulose of the nucleus(fig.2). In the silver stained Giardia cells, no nucleolus was found, a few silver grains were scattered in the nucleolus and did not concentrate in any specific region(fig.4). This result means that the rDNA of Giardia does not form a NOR\|like structure and that it seems to be in a very primitive state.

关 键 词：无核仁原生动物 蓝氏贾第虫 RDNA 分布 核仁组织区 银柒 细胞核 起源 

分 类 号：Q953[生物学—动物学]