title: Brief notes on the structural organization, cytochemistry and function of nucleoli.
abstract: A brief review of the structural and functional organization of the nucleolus is presented. On the ground of the distributive characteristics of the nucleolar RNA, nucleoli may be classified into several main types which form, at the same time, suitable indicators of their biosynthetic activity in the sense of transcription of this nucleic acid. This classification is also suitable for evaluating cellular activity, and it is already being used, actually, in certain medical fields including immunology. Ultrastructural studies of the nucleolus have verified the findings of classical light microscopy and have brought new information concerning the structural organization of the various individual nucleolar components, including their specific role. They have also helped to complement our current knowledge about the biochemistry of RNA synthesis and maturation. Presently, a great deal of attention is being paid to the protein components of the nucleolus. Some of these are, it seems, somehow related to or RNA transcription and maturation, to malignancy and proliferation, or the regulation of these processes.
mesh_terms: D002466:Cell Nucleolus / Q000378:metabolism / Q000502:physiology / Q000648:ultrastructure*; D006801:Humans