Polycistronic RNA polymerase II expression vectors for RNA interference based on miR-155

The E1a gene of adenovirus encodes two proteins, 289 and 243 amino acids long, which have positive (transactivator) and negative (enhancer repressor) RNA polymerase II transcriptional regulatory properties and cell transformation activities including cooperation with an activated ras gene. The E1a transforming functions more closely correlate with the repressor property than with transactivation in that both E1a proteins express the repressor and transformation functions while only the 289-amino-acid protein is an efficient transactivator. To understand whether the transcriptional regulatory activities of E1a are related to its ras cooperation activity, we generated a series of mutant E1a expression vectors by linker insertion mutagenesis of the 289-amino-acid protein. Here we describe a new class of mutants which although defective for enhancer repression still can cooperate with the ras oncogene in cell transformation. The mutants are also defective in transcription transactivation. Our data suggest that enhancer repression and transformation via ras cooperation are separate E1a functions and that cooperation with ras does not rely on either of the RNA polymerase II transcription regulatory functions of E1a. We also show that mutations which inactivate enhancer repression are not confirmed to a single critical domain necessary for repression. We therefore propose that the integrity of the overall configuration of the E1a proteins is important for the repression activity.

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Adenovirus E1a ras cooperation activity is separate from its positive and negative transcription regulatory functions

Molecular and Cellular Biology ◽

10.1128/mcb.8.5.2177-2183.1988 ◽

1988 ◽

Vol 8 (5) ◽

pp. 2177-2183

Author(s):

A Velcich ◽

E Ziff

Keyword(s):

Amino Acid ◽

Rna Polymerase ◽

Rna Polymerase Ii ◽

Cell Transformation ◽

Expression Vectors ◽

Insertion Mutagenesis ◽

Acid Protein ◽

Transcriptional Regulatory ◽

Regulatory Functions ◽

Amino Acid Protein

The E1a gene of adenovirus encodes two proteins, 289 and 243 amino acids long, which have positive (transactivator) and negative (enhancer repressor) RNA polymerase II transcriptional regulatory properties and cell transformation activities including cooperation with an activated ras gene. The E1a transforming functions more closely correlate with the repressor property than with transactivation in that both E1a proteins express the repressor and transformation functions while only the 289-amino-acid protein is an efficient transactivator. To understand whether the transcriptional regulatory activities of E1a are related to its ras cooperation activity, we generated a series of mutant E1a expression vectors by linker insertion mutagenesis of the 289-amino-acid protein. Here we describe a new class of mutants which although defective for enhancer repression still can cooperate with the ras oncogene in cell transformation. The mutants are also defective in transcription transactivation. Our data suggest that enhancer repression and transformation via ras cooperation are separate E1a functions and that cooperation with ras does not rely on either of the RNA polymerase II transcription regulatory functions of E1a. We also show that mutations which inactivate enhancer repression are not confirmed to a single critical domain necessary for repression. We therefore propose that the integrity of the overall configuration of the E1a proteins is important for the repression activity.

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Correction: RNA-interference-directed chromatin modification coupled to RNA polymerase II transcription

Nature ◽

10.1038/nature04181 ◽

2005 ◽

Vol 437 (7061) ◽

pp. 1057-1057 ◽

Cited By ~ 5

Author(s):

Vera Schramke ◽

Daniel M. Sheedy ◽

Ahmet M. Denli ◽

Carolina Bonila ◽

Karl Ekwall ◽

...

Keyword(s):

Rna Interference ◽

Rna Polymerase ◽

Rna Polymerase Ii ◽

Chromatin Modification ◽

Rna Polymerase Ii Transcription

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Nutrient-regulated gene expression in eukaryotes

Biochemical Society Symposium ◽

10.1042/bss0730085 ◽

2006 ◽

Vol 73 ◽

pp. 85-96 ◽

Cited By ~ 8

Author(s):

Richard J. Reece ◽

Laila Beynon ◽

Stacey Holden ◽

Amanda D. Hughes ◽

Karine Rébora ◽

...

Keyword(s):

Gene Expression ◽

Rna Polymerase ◽

Rna Polymerase Ii ◽

Transcriptional Control ◽

Direct Interaction ◽

Signalling Pathways ◽

A Cell ◽

One Step ◽

Higher Eukaryotes ◽

Regulated Gene Expression

The recognition of changes in environmental conditions, and the ability to adapt to these changes, is essential for the viability of cells. There are numerous well characterized systems by which the presence or absence of an individual metabolite may be recognized by a cell. However, the recognition of a metabolite is just one step in a process that often results in changes in the expression of whole sets of genes required to respond to that metabolite. In higher eukaryotes, the signalling pathway between metabolite recognition and transcriptional control can be complex. Recent evidence from the relatively simple eukaryote yeast suggests that complex signalling pathways may be circumvented through the direct interaction between individual metabolites and regulators of RNA polymerase II-mediated transcription. Biochemical and structural analyses are beginning to unravel these elegant genetic control elements.

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