Role of use a helix-loop-helk-zipper dna binding protein, in rRNA gene regulation

Asish K. Ghosh*, Prasun K. Datta, Samson T. Jacob

*Corresponding author for this work

Research output: Contribution to journalArticle

Abstract

Earlier studies from this laboratory demonstrated that the rat ribosomal RNA gene (rDNA) core promoter contains an E box-like sequence to which the core promoter-binding factor (CPBF) binds and that the 44 kDa subunit of this factor is immunologically related to USF. The competition by oligonucleotides containing USF-binding site further confirmed the role of USF, a helix-loop-helix-zipper DNA binding protein in rDNA transcription [Datta, P.K., Ghosh, A.K. and Jacob, S.T. (1995) J. Biol. Chem. 270:86378641J. To prove further the involvement of USF in rDNA regulation in vivo, the effect of USF1 and USF2 overexpression as homodimers and heterodimers was assayed by co-transfection of respective cDNAs and rDNA reporter construct into CHO cells. Primer extension analysis of the RNA synthesized from the reporter construct showed that overexpression of USF1 and USF2 individually resulted in inhibition of rDNA transcription by 8590% whereas overexpression of both the subunits of USF (USF1 and USF2) together activated pol I mediated transcription 3.5 fold. Transfection of a mutant USF2 cDNA devoid of the basic DNA binding domain produced minimal inhibition of rDNA transcription. This effect is E-box specific as overexpression of USF1 and USF2 individually or together did not influence the activity of a non-E box containing promoter such as S V40 promoter. This is the first report that USF can modulate pol I transcription and that it functions as a repressor or activator of pol I transcription in vivo depending upon the dimeric status of USF1 and USF2. This work was supported by an NIH grant CA31894. 'Equal contribution.

Original languageEnglish (US)
JournalFASEB Journal
Volume10
Issue number6
StatePublished - Dec 1 1996

Fingerprint

Fasteners
Transcription
Ribosomal DNA
rRNA Genes
Gene expression
binding proteins
Carrier Proteins
transcription (genetics)
ribosomal RNA
promoter regions
genes
transfection
Transfection
Complementary DNA
Core Binding Factors
E-Box Elements
Ribosomal RNA
DNA-binding proteins
DNA-binding domains
CHO Cells

ASJC Scopus subject areas

  • Agricultural and Biological Sciences (miscellaneous)
  • Biochemistry, Genetics and Molecular Biology(all)
  • Biochemistry
  • Cell Biology

Cite this

@article{d7fa0c325c6b45ed82c39acc957d51a6,
title = "Role of use a helix-loop-helk-zipper dna binding protein, in rRNA gene regulation",
abstract = "Earlier studies from this laboratory demonstrated that the rat ribosomal RNA gene (rDNA) core promoter contains an E box-like sequence to which the core promoter-binding factor (CPBF) binds and that the 44 kDa subunit of this factor is immunologically related to USF. The competition by oligonucleotides containing USF-binding site further confirmed the role of USF, a helix-loop-helix-zipper DNA binding protein in rDNA transcription [Datta, P.K., Ghosh, A.K. and Jacob, S.T. (1995) J. Biol. Chem. 270:86378641J. To prove further the involvement of USF in rDNA regulation in vivo, the effect of USF1 and USF2 overexpression as homodimers and heterodimers was assayed by co-transfection of respective cDNAs and rDNA reporter construct into CHO cells. Primer extension analysis of the RNA synthesized from the reporter construct showed that overexpression of USF1 and USF2 individually resulted in inhibition of rDNA transcription by 8590{\%} whereas overexpression of both the subunits of USF (USF1 and USF2) together activated pol I mediated transcription 3.5 fold. Transfection of a mutant USF2 cDNA devoid of the basic DNA binding domain produced minimal inhibition of rDNA transcription. This effect is E-box specific as overexpression of USF1 and USF2 individually or together did not influence the activity of a non-E box containing promoter such as S V40 promoter. This is the first report that USF can modulate pol I transcription and that it functions as a repressor or activator of pol I transcription in vivo depending upon the dimeric status of USF1 and USF2. This work was supported by an NIH grant CA31894. 'Equal contribution.",
author = "Ghosh, {Asish K.} and Datta, {Prasun K.} and Jacob, {Samson T.}",
year = "1996",
month = "12",
day = "1",
language = "English (US)",
volume = "10",
journal = "FASEB Journal",
issn = "0892-6638",
publisher = "FASEB",
number = "6",

}

Role of use a helix-loop-helk-zipper dna binding protein, in rRNA gene regulation. / Ghosh, Asish K.; Datta, Prasun K.; Jacob, Samson T.

In: FASEB Journal, Vol. 10, No. 6, 01.12.1996.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Role of use a helix-loop-helk-zipper dna binding protein, in rRNA gene regulation

AU - Ghosh, Asish K.

AU - Datta, Prasun K.

AU - Jacob, Samson T.

PY - 1996/12/1

Y1 - 1996/12/1

N2 - Earlier studies from this laboratory demonstrated that the rat ribosomal RNA gene (rDNA) core promoter contains an E box-like sequence to which the core promoter-binding factor (CPBF) binds and that the 44 kDa subunit of this factor is immunologically related to USF. The competition by oligonucleotides containing USF-binding site further confirmed the role of USF, a helix-loop-helix-zipper DNA binding protein in rDNA transcription [Datta, P.K., Ghosh, A.K. and Jacob, S.T. (1995) J. Biol. Chem. 270:86378641J. To prove further the involvement of USF in rDNA regulation in vivo, the effect of USF1 and USF2 overexpression as homodimers and heterodimers was assayed by co-transfection of respective cDNAs and rDNA reporter construct into CHO cells. Primer extension analysis of the RNA synthesized from the reporter construct showed that overexpression of USF1 and USF2 individually resulted in inhibition of rDNA transcription by 8590% whereas overexpression of both the subunits of USF (USF1 and USF2) together activated pol I mediated transcription 3.5 fold. Transfection of a mutant USF2 cDNA devoid of the basic DNA binding domain produced minimal inhibition of rDNA transcription. This effect is E-box specific as overexpression of USF1 and USF2 individually or together did not influence the activity of a non-E box containing promoter such as S V40 promoter. This is the first report that USF can modulate pol I transcription and that it functions as a repressor or activator of pol I transcription in vivo depending upon the dimeric status of USF1 and USF2. This work was supported by an NIH grant CA31894. 'Equal contribution.

AB - Earlier studies from this laboratory demonstrated that the rat ribosomal RNA gene (rDNA) core promoter contains an E box-like sequence to which the core promoter-binding factor (CPBF) binds and that the 44 kDa subunit of this factor is immunologically related to USF. The competition by oligonucleotides containing USF-binding site further confirmed the role of USF, a helix-loop-helix-zipper DNA binding protein in rDNA transcription [Datta, P.K., Ghosh, A.K. and Jacob, S.T. (1995) J. Biol. Chem. 270:86378641J. To prove further the involvement of USF in rDNA regulation in vivo, the effect of USF1 and USF2 overexpression as homodimers and heterodimers was assayed by co-transfection of respective cDNAs and rDNA reporter construct into CHO cells. Primer extension analysis of the RNA synthesized from the reporter construct showed that overexpression of USF1 and USF2 individually resulted in inhibition of rDNA transcription by 8590% whereas overexpression of both the subunits of USF (USF1 and USF2) together activated pol I mediated transcription 3.5 fold. Transfection of a mutant USF2 cDNA devoid of the basic DNA binding domain produced minimal inhibition of rDNA transcription. This effect is E-box specific as overexpression of USF1 and USF2 individually or together did not influence the activity of a non-E box containing promoter such as S V40 promoter. This is the first report that USF can modulate pol I transcription and that it functions as a repressor or activator of pol I transcription in vivo depending upon the dimeric status of USF1 and USF2. This work was supported by an NIH grant CA31894. 'Equal contribution.

UR - http://www.scopus.com/inward/record.url?scp=33748886508&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33748886508&partnerID=8YFLogxK

M3 - Article

VL - 10

JO - FASEB Journal

JF - FASEB Journal

SN - 0892-6638

IS - 6

ER -