|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | |||||
Journal of Cell Science, Vol 110, Issue 17 2053-2063, Copyright © 1997 by Company of Biologists
JOURNAL ARTICLES |
P Bell, C Mais, B McStay and U Scheer
Department of Cell and Developmental Biology, Theodor-Boveri-Institute, University of Wurzburg, Germany.
When nuclei (pronuclei) were assembled from sperm chromatin in Xenopus egg extract and examined by immunofluorescence microscopy, UBF was concentrated at a single intranuclear dot-like or more extended necklace-like structure. These UBF-foci contained rDNA as demonstrated by in situ hybridization and hence represent the chromosomal nucleolus organizing regions (NORs). Besides UBF, other components of the transcription machinery such as the TATA-box binding protein (TBP) and RNA polymerase I (pol I) as well as several nucleolar proteins could not be detected at the NORs. Immuno-depletion experiments indicated the UBF is maternally provided and taken up by the pronuclei. Essentially the same results were obtained when we examined the NORs of early Xenopus embryos up to the midblastula stage. After this stage, when transcription of the rRNA genes has begun, nucleoli developed and the NORs acquired TBP and pol I. Our results support the hypothesis that UBF is an architectural element which converts the rDNA chromatin into a transcriptionally competent form.
This article has been cited by other articles:
![]() |
C.-Y. Lin, S. Navarro, S. Reddy, and L. Comai CK2-mediated stimulation of Pol I transcription by stabilization of UBF-SL1 interaction Nucleic Acids Res., October 18, 2006; 34(17): 4752 - 4766. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. Baran, A. Pavlok, B. Bjerregaard, C. Wrenzycki, D. Hermann, V. V. Philimonenko, G. Lapathitis, P. Hozak, H. Niemann, and J. Motlik Immunolocalization of Upstream Binding Factor and Pocket Protein p130 During Final Stages of Bovine Oocyte Growth Biol Reprod, April 1, 2004; 70(4): 877 - 886. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. C. O'Sullivan, G. J. Sullivan, and B. McStay UBF Binding In Vivo Is Not Restricted to Regulatory Sequences within the Vertebrate Ribosomal DNA Repeat Mol. Cell. Biol., January 15, 2002; 22(2): 657 - 658. [Abstract] [Full Text] [PDF] |
||||
![]() |
C Mais and U Scheer Molecular architecture of the amplified nucleoli of Xenopus oocytes J. Cell Sci., January 2, 2001; 114(4): 709 - 718. [Abstract] [PDF] |
||||
![]() |
C. Verheggen, G. Almouzni, and D. Hernandez-Verdun The Ribosomal RNA Processing Machinery Is Recruited to the Nucleolar Domain before RNA Polymerase I during Xenopus laevis Development J. Cell Biol., April 17, 2000; 149(2): 293 - 306. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Hock, U. Scheer, and M. Bustin Chromosomal Proteins HMG-14 and HMG-17 Are Released from Mitotic Chromosomes and Imported into the Nucleus by Active Transport J. Cell Biol., December 14, 1998; 143(6): 1427 - 1436. [Abstract] [Full Text] [PDF] |
||||