scholarly journals Specific transcription of Saccharomyces cerevisiae 35 S rDNA by RNA polymerase I in vitro.

1990 ◽  
Vol 265 (13) ◽  
pp. 7596-7603
Author(s):  
D L Riggs ◽  
M Nomura
2019 ◽  
Vol 295 (5) ◽  
pp. 1288-1299 ◽  
Author(s):  
Catherine E. Scull ◽  
Andrew M. Clarke ◽  
Aaron L. Lucius ◽  
David Alan Schneider

The sequence of the DNA template has long been thought to influence the rate of transcription by DNA-dependent RNA polymerases, but the influence of DNA sequence on transcription elongation properties of eukaryotic RNA polymerase I (Pol I) from Saccharomyces cerevisiae has not been defined. In this study, we observe changes in dinucleotide production, transcription elongation complex stability, and Pol I pausing in vitro in response to downstream DNA. In vitro studies demonstrate that AT-rich downstream DNA enhances pausing by Pol I and inhibits Pol I nucleolytic cleavage activity. Analysis of Pol I native elongating transcript sequencing data in Saccharomyces cerevisiae suggests that these downstream sequence elements influence Pol I in vivo. Native elongating transcript sequencing studies reveal that Pol I occupancy increases as downstream AT content increases and decreases as downstream GC content increases. Collectively, these data demonstrate that the downstream DNA sequence directly impacts the kinetics of transcription elongation prior to the sequence entering the active site of Pol I both in vivo and in vitro.


1999 ◽  
Vol 19 (11) ◽  
pp. 7369-7376 ◽  
Author(s):  
Ronald H. Reeder ◽  
Palmira Guevara ◽  
Judith G. Roan

ABSTRACT We have mapped transcription termination sites for RNA polymerase I in the yeast Saccharomyces cerevisiae. S1 nuclease mapping shows that the primary terminator is the Reb1p terminator located at +93 downstream of the 3′ end of 25S rRNA. Reverse transcription coupled with quantitative PCR shows that approximately 90% of all transcripts terminate at this site. Transcripts which read through the +93 site quantitatively terminate at a fail-safe terminator located further downstream at +250. Inactivation of Rnt1p (an RNase III involved in processing the 3′ end of 25S rRNA) greatly stabilizes transcripts extending to both sites and increases readthrough at the +93 site. In vivo assay of mutants of the Reb1p terminator shows that this site operates in vivo by the same mechanism as has previously been delineated through in vitro studies.


1993 ◽  
Vol 13 (1) ◽  
pp. 649-658
Author(s):  
W H Lang ◽  
R H Reeder

We have identified a terminator for transcription by RNA polymerase I in the genes coding for rRNA of the yeast Saccharomyces cerevisiae. The terminator is located 108 bp downstream of the 3' end of the mature 25S rRNA and shares several characteristics with previously studied polymerase I terminators in the vertebrates. For example, the yeast terminator is orientation dependent, is inhibited by its own sequence, and forms RNA 3' ends 17 +/- 2 bp upstream of an essential protein binding site. The recognition sequence for binding of the previously cloned REB1 protein (Q. Ju, B. E. Morrow, and J. R. Warner, Mol. Cell. Biol. 10:5226-5234, 1990) is an essential component of the terminator. In addition, the efficiency of termination depends upon sequence context extending at least 12 bp upstream of the REB1 site.


1988 ◽  
Vol 8 (5) ◽  
pp. 1940-1946
Author(s):  
E Bateman ◽  
M R Paule

Chemical footprinting and topological analysis were carried out on the Acanthamoeba castellanii rRNA transcription initiation factor (TIF) and RNA polymerase I complexes with DNA during transcription initiation and elongation. The results show that the binding of TIF and polymerase to the promoter does not alter the supercoiling of the DNA template and the template does not become sensitive to modification by diethylpyrocarbonate, which can identify melted DNA regions. Thus, in contrast to bacterial RNA polymerase, the eucaryotic RNA polymerase I-promoter complex is in a closed configuration preceding addition of nucleotides in vitro. Initiation and 3'-O-methyl CTP-limited translocation by RNA polymerase I results in separation of the polymerase-TIF footprints, leaving the TIF footprint unaltered. In contrast, initiation and translocation result in a significant change in the conformation of the polymerase-DNA complex, culminating in an unwound DNA region of at least 10 base pairs.


2020 ◽  
Vol 295 (15) ◽  
pp. 4782-4795 ◽  
Author(s):  
Philipp E. Merkl ◽  
Michael Pilsl ◽  
Tobias Fremter ◽  
Katrin Schwank ◽  
Christoph Engel ◽  
...  

RNA polymerase I (Pol I) is a highly efficient enzyme specialized in synthesizing most ribosomal RNAs. After nucleosome deposition at each round of rDNA replication, the Pol I transcription machinery has to deal with nucleosomal barriers. It has been suggested that Pol I–associated factors facilitate chromatin transcription, but it is unknown whether Pol I has an intrinsic capacity to transcribe through nucleosomes. Here, we used in vitro transcription assays to study purified WT and mutant Pol I variants from the yeast Saccharomyces cerevisiae and compare their abilities to pass a nucleosomal barrier with those of yeast Pol II and Pol III. Under identical conditions, purified Pol I and Pol III, but not Pol II, could transcribe nucleosomal templates. Pol I mutants lacking either the heterodimeric subunit Rpa34.5/Rpa49 or the C-terminal part of the specific subunit Rpa12.2 showed a lower processivity on naked DNA templates, which was even more reduced in the presence of a nucleosome. Our findings suggest that the lobe-binding subunits Rpa34.5/Rpa49 and Rpa12.2 facilitate passage through nucleosomes, suggesting possible cooperation among these subunits. We discuss the contribution of Pol I–specific subunit domains to efficient Pol I passage through nucleosomes in the context of transcription rate and processivity.


1993 ◽  
Vol 13 (1) ◽  
pp. 114-122 ◽  
Author(s):  
Y Nogi ◽  
R Yano ◽  
J Dodd ◽  
C Carles ◽  
M Nomura

We have previously isolated mutants of Saccharomyces cerevisiae that are primarily defective in transcription of 35S rRNA genes by RNA polymerase I and have identified genes (RRN1 to RRN9) involved in this process. We have now cloned the RRN4 gene by complementation of the temperature-sensitive phenotype of the rrn4-1 mutant and have determined its complete nucleotide sequence. The following results demonstrate that the RRN4 gene encodes the A12.2 subunit of RNA polymerase I. First, RRN4 protein expressed in Escherichia coli reacted with a specific antiserum against A12.2. Second, amino acid sequences of three tryptic peptides obtained from A12.2 were determined, and these sequences are found in the deduced amino acid sequence of the RRN4 protein. The amino acid sequence of the RRN4 protein (A12.2) is similar to that of the RPB9 (B12.6) subunit of yeast RNA polymerase II; the similarity includes the presence of two putative zinc-binding domains. Thus, A12.2 is a homolog of B12.6. We propose to rename the RRN4 gene RPA12. Deletion of RPA12 produces cells that are heat but not cold sensitive for growth. We have found that in such null mutants growing at permissive temperatures, the cellular concentration of A190, the largest subunit of RNA polymerase I, is lower than in the wild type. In addition, the temperature-sensitive phenotype of the rpa12 null mutants can be partially suppressed by RPA190 (the gene for A190) on multicopy plasmids. These results suggest that A12.2 plays a role in the assembly of A190 into a stable polymerase I structure.


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