» Articles » PMID: 7958901

RRN6 and RRN7 Encode Subunits of a Multiprotein Complex Essential for the Initiation of RDNA Transcription by RNA Polymerase I in Saccharomyces Cerevisiae

Overview
Journal Genes Dev
Specialty Molecular Biology
Date 1994 Oct 1
PMID 7958901
Citations 50
Authors
Affiliations
Soon will be listed here.
Abstract

Previously, we have isolated mutants of Saccharomyces cerevisiae primarily defective in the transcription of 35S rRNA genes by RNA polymerase I and have identified a number of genes (RRN genes) involved in this process. We have now cloned the RRN6 and RRN7 genes, determined their nucleotide sequences, and found that they encode proteins of calculated molecular weights of 102,000 and 60,300, respectively. Extracts prepared from rrn6 and rrn7 mutants were defective in in vitro transcription of rDNA templates. We used extracts from strains containing epitope-tagged wild-type Rrn6 or Rrn7 proteins to purify protein components that could complement these mutant extracts. By use of immunoaffinity purification combined with biochemical fractionation, we obtained a highly purified preparation (Rrn6/7 complex), which consisted of Rrn6p, Rrn7p, and another protein with an apparent molecular weight of 66,000, but which did not contain the TATA-binding protein (TBP). This complex complemented both rrn6 and rrn7 mutant extracts. Template commitment experiments carried out with this purified Rrn6/7 complex and with rrn6 mutant extracts have demonstrated that the Rrn6/7 complex does not bind stably to the rDNA template by itself, but its binding is dependent on the initial binding of some other factor(s) and that the Rrn6/7 complex is required for the formation of a transcription-competent preinitiation complex. These observations are discussed in comparison to in vitro rDNA transcription systems from higher eukaryotes.

Citing Articles

Establishment of closed 35S ribosomal RNA gene chromatin in stationary Saccharomyces cerevisiae cells.

Babl V, Girke P, Kruse S, Pinz S, Hannig K, Schachner C Nucleic Acids Res. 2024; 52(20):12208-12226.

PMID: 39373531 PMC: 11551728. DOI: 10.1093/nar/gkae838.


Comparative Research: Regulatory Mechanisms of Ribosomal Gene Transcription in and .

Hirai H, Ohta K Biomolecules. 2023; 13(2).

PMID: 36830657 PMC: 9952952. DOI: 10.3390/biom13020288.


The Structures of Eukaryotic Transcription Pre-initiation Complexes and Their Functional Implications.

Greber B, Nogales E Subcell Biochem. 2020; 93:143-192.

PMID: 31939151 PMC: 7025760. DOI: 10.1007/978-3-030-28151-9_5.


Conditional depletion of the RNA polymerase I subunit PAF53 reveals that it is essential for mitosis and enables identification of functional domains.

McNamar R, Abu-Adas Z, Rothblum K, Knutson B, Rothblum L J Biol Chem. 2019; 294(52):19907-19922.

PMID: 31727736 PMC: 6937585. DOI: 10.1074/jbc.RA119.009902.


The C-terminal region of Net1 is an activator of RNA polymerase I transcription with conserved features from yeast to human.

Hannig K, Babl V, Hergert K, Maier A, Pilsl M, Schachner C PLoS Genet. 2019; 15(2):e1008006.

PMID: 30802237 PMC: 6415870. DOI: 10.1371/journal.pgen.1008006.