草鱼染色体的包装（间期—中期）

以草鱼ＺＣ７９０１细胞株为材料,观察鱼类细胞从间期染色质到中期染色体的包装过程。主要通过（１）分裂期与间期细胞融合,诱导染色体早熟凝集;（２）染色体“伸长”处理;（３）培养细胞的低渗处理;（４）染色质辅展等方法,制作染色体标本,进行扫描和透射电镜观察。观察表明,鱼类染色质的基本结构与哺乳类细胞相同,也是直径约１０ｎｍ的核丝。染色体的色装有两种形式：一种是多级螺旋化形成直径约３００ｎｍ的染色单体,

CHROMOSOME PACKING OF THE GRASSCARP (Ctenopharyngodon idellus) FROMINTERPHASE TO METAPHASE

The cell strain ZC-7901 of Grass Carp snout tissue was adopted for the research of packing from basic chromatin fibres to chromosomes. In studying of the subject, four methods were used: the induction of premature chromosome condensation in interphase nuclei by fusing with metaphase cell; the "elongation" of chromosomes; the moderate hypo-osmosis of culture cells and spreading chromatin. Scanning and transmission electron microscopes were used to investigate the prepared specimens. The observations showed that the basic structure of fish chromatin was the same as that of mammalians, which was the nucleofilament of 10 nm in diameter. There were two patterns from the chromatin packing into the chromosome: one was the multiple spiralization from the basic fibre into the chromatid of about 300 nm in diameter, and then to the sister chromatids which twisted into the chromosome; the other one was the directly fold coupling from 30 nm or 60 nm solenoids into the chromosome in which the partial helical irregular fibres coexisted. It was suggested that the spiralization was the normal packing pattern of the chromosomes of Grass Carp, and the fold coupling was the rapid and premature condensation.