有丝分裂前期蚕豆核仁解体的电镜观察

TEM OBSERVATIONS ON THE DISINTEGRATION OF BROADBEAN(VICIA FABA)NUCLEOLI DURING MITOTIC PROPHASE

Ultrastructural and cytochemical studies on the disintegration of broadbean nucleoli during mitotic prophase were carried out with conventional staining tcchnique and RNP preferential staining technique (BernhardPs technique).We observed that the changes In shape and the gradual reduction in size of the nucleolus were accompanied by the dispersion of nucleolar RNP material in the surrounding nuclear sap. Furthermore,two special events were noticed:the early condensation of the chromatin which was related to the nucleolus,and the persis- tence of a condensed structre that appeared among the disintegrated nucleolus at the end of prophase.The significance of these events, in relation to the condensation of nucleolar chromatin and the nature of persistent nucleoli,is discussed in this paper.