title: Does the synthesis of ribosomal RNA take place within nucleolar fibrillar centers or dense fibrillar components?
abstract: By means of immunocytochemistry performed on cryosections of cultured cells, RNA polymerase I was localized mainly to nucleolar fibrillar centers. The labelling of nucleolar dense fibrillar components was low and depended on the cell type. In contrast, DNA topoisomerase I and RNP complexes containing U3 snRNA were enriched in dense fibrillar components, their occurrence in fibrillar centers being usually much less.
authors.affiliation: Institute of Experimental Medicine, Czechoslovak Academy of Sciences, Prague.
authors.forename: I
authors.initials: I
authors.lastname: Raska
authors.forename: G
authors.initials: G
authors.lastname: Reimer
authors.forename: M
authors.initials: M
authors.lastname: Jarník
authors.forename: Z
authors.initials: Z
authors.lastname: Kostrouch
authors.forename: K
authors.initials: K
authors.lastname: Raska
mesh_terms: D000310:Adrenal Gland Neoplasms; D000818:Animals; D002460:Cell Line; D002466:Cell Nucleolus / Q000378:metabolism* / Q000648:ultrastructure; D004264:DNA Topoisomerases, Type I / Q000378:metabolism; D006367:HeLa Cells / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008854:Microscopy, Electron; D010673:Pheochromocytoma; D012318:RNA Polymerase I / Q000378:metabolism; D012335:RNA, Ribosomal / Q000096:biosynthesis*; D051381:Rats
chemical_list: D012335:RNA, Ribosomal; D012318:RNA Polymerase I; D004264:DNA Topoisomerases, Type I