摘要
本文报道了有丝分裂过程中蚕豆(Vicia faba)根端分生组织细胞内一种由核仁物质组成的特殊结构,我们将其称作核仁残体。经常规染色后,可在前期末正在分散的核仁物质中看到由直径15—20nm 的颗粒和纤维组成的核仁残体;前中期时,核仁残体附着在染色体上,其电子密度低于染色体。Bernhard 染色结果表明,核仁残体的主要成分是核糖核蛋白(RNP)颗粒和纤维,一些核仁残体中存在着与染色质染色反应相似的被漂白区。有的核仁残体附着在中、后期染色体上,有的游离存在于细胞质中。本文讨论了核仁残体的成分及其本质等问题。
A special structure which originates from the nucleolus and persists during mitosis is observed in meristematic cells of Vicia faba,and is called nucleolar residual in this paper. The result of conventional staining showed that the nucleolar residual (NR) was a medium electron-dense structure that could be distinguished from chromosomes.At the end of proph- ase,the NR was observed in the dispersing nucleolar material,which consisted principally of granules and fibrils about 15 to 20 nm in diameter.In prometaphase,the NR,composed ma- inly of the similar granules and fibrils,was found attached to chromosomes.Results of Bern- hard's technique for RNP (ribonucleoprotein) preferential staining indicated that the main chemical component of the NR was RNP,and sometimes bleached regions showing the same reaction as chromatin in Bernhard's staining appeared in the structure.In metaphase and an- aphase some of the NRs were attached to chromosomes while others existed randomly in the cytoplasm.The NR is supposed,according to its cytochemical features and its behaviour du- ring the nucleolar disintegration,to be a structure composed mainly of nucleolar matrix ma- terial or nucleolar skeleton.
关键词
蚕豆
核仁残体
Nucleolar residual
Nucleolar matrix
Persistent nucleoli
Vicia fabe
