Localization of rDNA transcription sites in nucleoli of human Sertoli cells: An EM quantitative autoradiographic study using super(3)H-uridine

• Published in: Biology of the cell Vol. 81; no. 3; pp. 247 - 256
• Main Authors: Brechard, M-P, Hartung, M, de Lanversin, A, Cau, P, Stahl, A
• Format: Journal Article
• Language: English
• Published: 01.01.1994
• ISSN: 0248-4900

The sites of rDNA transcription within human Sertoli cell nucleoli have been localized using EM autoradiography after a 45-min pulse of super(3)H-uridine and an exposure time of 6 months. Two successive quantitative image analyses, one derived from the 50% probability circle method and the other from the cross-fire method, allowed us to estimate the radioactivity incorporated within each nucleolus compartment. This study demonstrated that rDNA transcription occurred mainly at the border between fibrillar centers and dense fibrillar components and to a lesser extent within the dense fibrillar component. The other Sertoli cell nucleoli compartments did not incorporate super(3)H-uridine and therefore were not involved in rDNA transcription.