Abstract:
:Pre-rRNA synthesis and processing are key steps in ribosome biogenesis. Although recent evidence in yeast suggests that these two processes are coupled, the nature of their association is unclear. In this report, we analyze the coordination between rDNA transcription and pre-rRNA processing in mammalian cells. We found that pol I transcription factor UBF interacts with pre-rRNA processing factors as analyzed by immunoprecipitations, and the association depends on active rRNA synthesis. In addition, injections of plasmids containing the human rDNA promoter and varying lengths of 18S rDNA into HeLa nuclei show that pol I transcription machinery can be recruited to rDNA promoters regardless of the product that is transcribed, whereas subgroups of pre-rRNA processing factors are recruited to plasmids only when specific pre-rRNA fragments are produced. Our observations suggest a model for sequential recruitment of pol I transcription factors and pre-rRNA processing factors to elongating pre-rRNA on an as-needed basis rather than corecruitment to sites of active transcription.
journal_name
Mol Biol Celljournal_title
Molecular biology of the cellauthors
Kopp K,Gasiorowski JZ,Chen D,Gilmore R,Norton JT,Wang C,Leary DJ,Chan EK,Dean DA,Huang Sdoi
10.1091/mbc.e06-03-0249subject
Has Abstractpub_date
2007-02-01 00:00:00pages
394-403issue
2eissn
1059-1524issn
1939-4586pii
E06-03-0249journal_volume
18pub_type
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