Transcription elongation regulator 1 (TCERG1) regulates competent RNA polymerase II-mediated elongation of HIV-1 transcription and facilitates efficient viral replication

The human immunodeficiency virus 1 (HIV-1) Rev transactivator protein plays a critical role in the regulation of expression of structural proteins by controlling the pathway of mRNA transport. The Rev protein is located predominantly in the nucleoli of HIV-1 infected or Rev-expressing cells. Previous studies demonstrated that the Rev protein forms a specific complex in vitro with protein B23 which is suggested to be a nucleolar receptor and/or carrier for the Rev protein. To study the role of the nucleolus and nucleolar proteins in Rev function, transfected COS-7 or transformed CMT3 cells expressing the Rev protein were examined for subcellular locations of Rev and other proteins using indirect immunofluorescence and immunoelectron microscopy. One day after transfection the Rev protein was found in most cells only in the nucleolar dense fibrillar and granular components where it colocalized with protein B23. These were designated class 1 cells. In a second class of cells Rev and B23 accumulated in the nucleoplasm as well as in nucleoli. Treatment of class 1 cells with actinomycin D (AMD) under conditions that blocked only RNA polymerase I transcription caused Rev to completely redistribute from nucleoli to the cytoplasm. Simultaneously, protein B23 was partially released from nucleoli, mostly into the nucleoplasm, with detectable amounts in the cytoplasm. In cells recovering from AMD treatment in the presence of cycloheximide Rev and B23 showed coincident relocation to nucleoli. Class 2 cells were resistant to AMD-induced Rev redistribution. Selective inhibition of RNA polymerase II transcription by alpha-amanitin or by DRB did not cause Rev to be released into the cytoplasm suggesting that active preribosomal RNA transcription is required for the nucleolar location of Rev. However, treatment with either of the latter two drugs at higher doses and for longer times caused partial disruption of nucleoli accompanied by translocation of the Rev protein to the cytoplasm. These results suggest that the nucleolar location of Rev depends on continuous preribosomal RNA transcription and a substantially intact nucleolar structure.

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Herpes Simplex Virus 1 (HSV-1) ICP22 Protein Directly Interacts with Cyclin-Dependent Kinase (CDK)9 to Inhibit RNA Polymerase II Transcription Elongation

PLoS ONE ◽

10.1371/journal.pone.0107654 ◽

2014 ◽

Vol 9 (9) ◽

pp. e107654 ◽

Cited By ~ 16

Author(s):

Justyna Zaborowska ◽

Sonja Baumli ◽

Clelia Laitem ◽

Dawn O'Reilly ◽

Peter H. Thomas ◽

...

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

Rna Polymerase ◽

Rna Polymerase Ii ◽

Transcription Elongation ◽

Cyclin Dependent Kinase ◽

Herpes Simplex Virus 1 ◽

Simplex Virus ◽

Rna Polymerase Ii Transcription ◽

Hsv 1

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Crystal structure of the human transcription elongation factor DSIF hSpt4 subunit in complex with the hSpt5 dimerization interface

Biochemical Journal ◽

10.1042/bj20091422 ◽

2009 ◽

Vol 425 (2) ◽

pp. 373-380 ◽

Cited By ~ 22

Author(s):

Sabine Wenzel ◽

Berta M. Martins ◽

Paul Rösch ◽

Birgitta M. Wöhrl

Keyword(s):

Crystal Structure ◽

Escherichia Coli ◽

Transcription Factor ◽

Rna Polymerase ◽

Rna Polymerase Ii ◽

Transcriptional Activation ◽

Transcription Elongation ◽

Elongation Factor ◽

Structural Similarity ◽

Transcription Elongation Factor

The eukaryotic transcription elongation factor DSIF [DRB (5,6-dichloro-1-β-D-ribofuranosylbenzimidazole) sensitivity-inducing factor] is composed of two subunits, hSpt4 and hSpt5, which are homologous to the yeast factors Spt4 and Spt5. DSIF is involved in regulating the processivity of RNA polymerase II and plays an essential role in transcriptional activation of eukaryotes. At several eukaryotic promoters, DSIF, together with NELF (negative elongation factor), leads to promoter-proximal pausing of RNA polymerase II. In the present paper we describe the crystal structure of hSpt4 in complex with the dimerization region of hSpt5 (amino acids 176–273) at a resolution of 1.55 Å (1 Å=0.1 nm). The heterodimer shows high structural similarity to its homologue from Saccharomyces cerevisiae. Furthermore, hSpt5-NGN is structurally similar to the NTD (N-terminal domain) of the bacterial transcription factor NusG. A homologue for hSpt4 has not yet been found in bacteria. However, the archaeal transcription factor RpoE” appears to be distantly related. Although a comparison of the NusG-NTD of Escherichia coli with hSpt5 revealed a similarity of the three-dimensional structures, interaction of E. coli NusG-NTD with hSpt4 could not be observed by NMR titration experiments. A conserved glutamate residue, which was shown to be crucial for dimerization in yeast, is also involved in the human heterodimer, but is substituted for a glutamine residue in Escherichia coli NusG. However, exchanging the glutamine for glutamate proved not to be sufficient to induce hSpt4 binding.

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BRCA2 Regulates Transcription Elongation by RNA Polymerase II to Prevent R-Loop Accumulation

Cell Reports ◽

10.1016/j.celrep.2017.12.086 ◽

2018 ◽

Vol 22 (4) ◽

pp. 1031-1039 ◽

Cited By ~ 44

Author(s):

Mahmud K.K. Shivji ◽

Xavier Renaudin ◽

Çiğdem H. Williams ◽

Ashok R. Venkitaraman

Keyword(s):

Rna Polymerase ◽

Rna Polymerase Ii ◽

Transcription Elongation

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The Rpb6 Subunit of Fission Yeast RNA Polymerase II Is a Contact Target of the Transcription Elongation Factor TFIIS

Molecular and Cellular Biology ◽

10.1128/mcb.20.4.1263-1270.2000 ◽

2000 ◽

Vol 20 (4) ◽

pp. 1263-1270 ◽

Cited By ~ 23

Author(s):

Akira Ishiguro ◽

Yasuhisa Nogi ◽

Koji Hisatake ◽

Masami Muramatsu ◽

Akira Ishihama

Keyword(s):

Rna Polymerase ◽

Fission Yeast ◽

Rna Polymerase Ii ◽

Transcription Elongation ◽

Elongation Factor ◽

Direct Interaction ◽

Temperature Sensitive ◽

Single Mutation ◽

Transcription Elongation Factor ◽

Essential Region

ABSTRACT The Rpb6 subunit of RNA polymerase II is one of the five subunits common to three forms of eukaryotic RNA polymerase. Deletion and truncation analyses of the rpb6 gene in the fission yeastSchizosaccharomyces pombe indicated that Rpb6, consisting of 142 amino acid residues, is an essential protein for cell viability, and the essential region is located in the C-terminal half between residues 61 and 139. After random mutagenesis, a total of 14 temperature-sensitive mutants were isolated, each carrying a single (or double in three cases and triple in one) mutation. Four mutants each carrying a single mutation in the essential region were sensitive to 6-azauracil (6AU), which inhibits transcription elongation by depleting the intracellular pool of GTP and UTP. Both 6AU sensitivity and temperature-sensitive phenotypes of these rpb6 mutants were suppressed by overexpression of TFIIS, a transcription elongation factor. In agreement with the genetic studies, the mutant RNA polymerases containing the mutant Rpb6 subunits showed reduced affinity for TFIIS, as measured by a pull-down assay of TFIIS-RNA polymerase II complexes using a fusion form of TFIIS with glutathioneS-transferase. Moreover, the direct interaction between TFIIS and RNA polymerase II was competed by the addition of Rpb6. Taken together, the results lead us to propose that Rpb6 plays a role in the interaction between RNA polymerase II and the transcription elongation factor TFIIS.

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A Role for SSU72 in Balancing RNA Polymerase II Transcription Elongation and Termination

Molecular Cell ◽

10.1016/s1097-2765(02)00707-4 ◽

2002 ◽

Vol 10 (5) ◽

pp. 1139-1150 ◽

Cited By ~ 103

Author(s):

Bernhard Dichtl ◽

Diana Blank ◽

Martin Ohnacker ◽

Arno Friedlein ◽

Daniel Roeder ◽

...

Keyword(s):

Rna Polymerase ◽

Rna Polymerase Ii ◽

Transcription Elongation ◽

Rna Polymerase Ii Transcription

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Sub1 associates with Spt5 and influences RNA polymerase II transcription elongation rate

Molecular Biology of the Cell ◽

10.1091/mbc.e12-04-0331 ◽

2012 ◽

Vol 23 (21) ◽

pp. 4297-4312 ◽

Cited By ~ 18

Author(s):

Alicia García ◽

Alejandro Collin ◽

Olga Calvo

Keyword(s):

Rna Polymerase ◽

Rna Polymerase Ii ◽

Transcription Elongation ◽

Elongation Factor ◽

Molecular Data ◽

Elongation Rate ◽

Dependent Manner ◽

Gene Encoding ◽

Mrna Metabolism ◽

Carboxy Terminal

The transcriptional coactivator Sub1 has been implicated in several steps of mRNA metabolism in yeast, such as the activation of transcription, termination, and 3′-end formation. In addition, Sub1 globally regulates RNA polymerase II phosphorylation, and most recently it has been shown that it is a functional component of the preinitiation complex. Here we present evidence that Sub1 plays a significant role in transcription elongation by RNA polymerase II (RNAPII). We show that SUB1 genetically interacts with the gene encoding the elongation factor Spt5, that Sub1 influences Spt5 phosphorylation of the carboxy-terminal domain of RNAPII largest subunit by the kinase Bur1, and that both Sub1 and Spt5 copurify in the same complex, likely during early transcription elongation. Indeed, our data indicate that Sub1 influences Spt5–Rpb1 interaction. In addition, biochemical and molecular data show that Sub1 influences transcription elongation of constitutive and inducible genes and associates with coding regions in a transcription-dependent manner. Taken together, our results indicate that Sub1 associates with Spt5 and influences Spt5–Rpb1 complex levels and consequently transcription elongation rate.

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