多头绒泡菌细胞核周期的电镜研究

ELECTRON MICROSCOPY STUDIES ON THE NUCLEAR CYCLE OF PHYSARUM POLYCEPHALUM

多头绒泡菌PhysarumpolycophalumSchw的营养生长阶段为没有细胞壁的原生质团（合胞体）,内部众多的细胞核进行着同步的核内有丝分裂,本文电镜下研究了细胞核在有丝分裂周期中的结构变化。有丝分裂前期,染色质经松散改组和集缩形成染色体,核仁由中央移向边缘,并在近核膜处解体;中期核膜不消失,在核内形成纺锤体,核仁解体后的物质是不规则状散在于核内;有丝分裂后核膜的破裂处重新愈合,染色体解集缩成染色质,分散的核仁物质逐渐合并形成新的核仁。

Nutrional growing stage of Physarum polycephalum Schw. was cell wall-less plasmodia in which numerous nuclei undertook synclironous intranuclear whtosis. in ths paper, the ultrastructural changes of nuclei in the mitohc cycle were studied with electron microscopy. At prophase, chromatin assembled into chromosome thorugh the process of reorganization and condensation, and nucleolus moved from the center to the edge of nucleus and disintegrated at the place near the nuclear membrane.At metaphase, nuclear membrane did not disappear; the mitohc spindle was formed within the nucleus, and the unregular disintegrated nucleolar materials dispersed in the nucleus. After mitosis, the nuclear membrane recovered in the brokened areas;chromosome discondensed into chromatin, and nucleolus was reformed by coalescence.