华美游仆虫大、小核的透射电镜和生化抽提扫描电镜观察

TEM and Biochemical Extraction-SEM Observation on Macroand Micronucleus of Euplotes elegans(Protozoan,Ciliophora)

应用透射电镜术和生化抽提扫描电镜术显示,华美游仆虫大核核膜表面形成孔状结构,并有相当数量的附着物;小核核膜表面也有孔状结构,但附着物较少.此外,非分裂期大核染色质凝缩排列形成染色质团,染色质团由染色质颗粒构成,各个染色质颗粒含有许多均质的染色质小体;大核DNA合成期间,大核复制带区的染色质团分解成染色质小体.据所得结果认为,染色质小体是构成游仆虫大核的基本结构单元;大、小核形态上的差异与其在无性生殖期间核、质间的功能活动及物质联系有关.

By using the methods of transmission electron microscopy （TEM） and biochemical extraction-scanning electron microscopy （SEM）, it was found that the macronucleus and micronucleus of the ciliated protozoan Euplotes elegans display different characteristics. The rnacronuclear surface is detected to sparse with lots of particles and dented; whereas the surface of micronucleus is distributed with few recesses and minute particles. In addition, the macronuclear chromatin is condensed into lumps, which consist of chromatin granules compose of homogenous bodies, the chromatin decomposed into granules in the area of replication band during DNA synthesis. Based on these results, we then proposed that the chromatin bodies are the basic units of macronucleus of Euplotes ; these morphological differences are closely related with their functions in asexual reproduction phase.