鱼类微细胞和小分离细胞制备技术的研究

STUDIES ON THE TECHNIQUES FOR THE PREPARATION OF FISH MICROCELLS AND MINISEGREGANT CELLS

本文以3种鱼类组织细胞系为材料,对鱼类微细胞和小分离细胞制备技术及其形成机制进行了研究。在微细胞制备中,观察了细胞的微核化过程,微核是由间期状态的细胞核不规则分裂而成。光镜和扫描电镜观察表明,在小分离细胞聚集体形成过程中,细胞核的变化与微细胞的微核化过程相一致,但其细胞质的分裂机制不同,当细胞质进行异常分裂的同时,细胞的微核也随同细胞质不规则分裂而被分配至各个小分离细胞内。

Using CAB-80 CAG-87 and CCRV-87 (these cell lines were devived from crucian carp blastula, caudal fin of crucian carp and caudal fin of Xingguo red carp respectively), we studied the preparation of fish microcells and minisegregant cells and the mechanism of their formation. In the preparation of microcells, observations were made on the process of micronucleation. The formation of micronuclei was the result of irregular division of interphase nuclei. We also studied the effects of colcemid concentration and treatment time on the proportions of micronucleated cells in the three cell lines. The proportion of micronucleation achieved was 40％ for CAB-80, and 30％ for CCRV-87 and CAG-87. High concentrations of colcemid or prolonged treatment time is toxic to the cells. The main procedures which can yield large quantities of fish minisegregant cells are as follows, 16-20 hours after incubation, colcemid is added to the cultures of CAB-80 cells at a final concentration of 0.3μg/ml. Mitotic cells are obtained by continuing incubation for another 10—14 hours. Then the mitotic-blocked ceils are collected and stored at 4℃ for 10 hours. At a temperature of 27℃ and a pH of 8.0, many cells display highly irregular patterns of division and about 50％ of them form minisegregant cells. Analysis of genetic material distribution and scanning electron microscopy showed that, in the formation of minisegregant cells, the process of nucleus change is the same as that of micronucleation, however, the mechanism of cytokinesis is different. Micronuclei are separated into many daughter cells due to the irregular cleavage of the cytoplasm.