caa a22 4500 475774663 CHVBK 20180406123627.0 cr unu---uuuuu 170329e20000301xx s 000 0 eng 10.1007/s004180050437 doi (NATIONALLICENCE)springer-10.1007/s004180050437 Ultrastructural analysis of nucleolar transcription in cells microinjected with 5-bromo-UTP [Elektronische Daten] [D. Cmarko, P. J. Verschure, L. I. Rothblum, D. Hernandez-Verdun, F. Amalric, R. van Driel, S. Fakan] Abstract : In situ sites of nucleolar transcription in cells microinjected with 5-bromo-UTP (BrUTP) were visualized at an ultrastructural level. After injection the cells were maintained for 4-90 min at 37°C, fixed, and embedded in LR White resin. Postembedding immunoelectron microscopic visualization with colloidal gold has been used for localizing both Br-labeled precursor incorporated into pre-rRNA and different nucleolar transcription or processing factors. This high resolution approach allowed us to identify significant signal as early as after 4-min incubation periods following BrUTP microinjection. It revealed the dense fibrillar component (DFC) as being the first nucleolar compartment labeled with anti-bromodeoxyuridine antibody. Moreover, RNA polymerase I, nucleolar transcription factor UBF, and fibrillarin were also detected almost exclusively in this same nucleolar compartment. From 30 min onward, following microinjection, Br-labeled rRNA occurred also in the granular component. The results indicate that the DFC is the site of pre-rRNA transcription and of initial steps of pre-rRNA processing. Moreover, it demonstrates that BrUTP microinjection followed by postembedding detection of Br- labeled RNA is a useful technique for high resolution studies of structure-function associations in the nucleolus. Springer-Verlag Berlin Heidelberg, 2000 Cmarko D. Centre of Electron Microscopy, University of Lausanne, 27 Bugnon, 1005 Lausanne, Switzerland e-mail: sfakan@cme.unil.ch Tel.: +41-21-6925052, Fax: +41-21-6925055, CH aut Verschure P. J. E.C. Slater Instituut, University of Amsterdam, 1018 TV Amsterdam, The Netherlands, NL aut Rothblum L. I. Weis Center for Research, Pennsylvania State University College of Medicine, Danville, PA 17822, USA, US aut Hernandez-Verdun D. Institute Jacques Monod, 75251 Paris, France, FR aut Amalric F. Institut de Pharmacologie et de Biologie Structurale, CNRS, 31077 Toulouse, France, FR aut van Driel R. E.C. Slater Instituut, University of Amsterdam, 1018 TV Amsterdam, The Netherlands, NL aut Fakan S. Centre of Electron Microscopy, University of Lausanne, 27 Bugnon, 1005 Lausanne, Switzerland e-mail: sfakan@cme.unil.ch Tel.: +41-21-6925052, Fax: +41-21-6925055, CH aut https://doi.org/10.1007/s004180050437 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s004180050437 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Cmarko D. Centre of Electron Microscopy, University of Lausanne, 27 Bugnon, 1005 Lausanne, Switzerland e-mail: sfakan@cme.unil.ch Tel.: +41-21-6925052, Fax: +41-21-6925055, CH aut NATIONALLICENCE 700 1- Verschure P. J. E.C. Slater Instituut, University of Amsterdam, 1018 TV Amsterdam, The Netherlands, NL aut NATIONALLICENCE 700 1- Rothblum L. I. Weis Center for Research, Pennsylvania State University College of Medicine, Danville, PA 17822, USA, US aut NATIONALLICENCE 700 1- Hernandez-Verdun D. Institute Jacques Monod, 75251 Paris, France, FR aut NATIONALLICENCE 700 1- Amalric F. Institut de Pharmacologie et de Biologie Structurale, CNRS, 31077 Toulouse, France, FR aut NATIONALLICENCE 700 1- van Driel R. E.C. Slater Instituut, University of Amsterdam, 1018 TV Amsterdam, The Netherlands, NL aut NATIONALLICENCE 700 1- Fakan S. Centre of Electron Microscopy, University of Lausanne, 27 Bugnon, 1005 Lausanne, Switzerland e-mail: sfakan@cme.unil.ch Tel.: +41-21-6925052, Fax: +41-21-6925055, CH aut Metadata rights reserved Springer special CC-BY-NC licence nationallicence SWISSBIB 439664225 BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer