PMID: 2498320May 25, 1989Paper

Polyamines differentially modulate the transcription of growth-associated genes in human colon carcinoma cells

The Journal of Biological Chemistry
P CelanoRobert A Casero

Abstract

Increases in the transcription of genes important to cell growth frequently occur in concert with increases in intracellular polyamines after a mitogenic stimulus. Previously, we have shown that depletion of intracellular polyamines by 2-difluoromethylornithine in COLO 320 cells resulted in a significant decrease in c-myc mRNA steady state levels. We demonstrate here that polyamines have a predominant role in the regulation of transcription of c-myc, c-fos, and histone 2A, while they appear to have both a transcriptional and post-transcriptional role in expression of c-myb, ornithine decarboxylase, and beta-actin mRNA levels. We further analyzed the effect of spermidine in overall and specific RNA transcription in isolated nuclei from COLO 320 cells. In nuclei from control cells, the addition of spermidine resulted in a 3-4 increase in overall [alpha-32P]UTP incorporation and a 4-8-fold increase in c-myc, c-fos, and histone 2A transcription. In contrast, ornithine decarboxylase and c-myb gene transcription were unaffected. Furthermore, in nuclei from 2-difluoromethylornithine-treated COLO 320 cells, spermidine addition resulted in less than a 2-fold increase in RNA transcription and had no effect on any specific gene analyzed. ...Continue Reading

Related Concepts

Related Feeds

ASBMB Publications

The American Society for Biochemistry and Molecular Biology (ASBMB) includes the Journal of Biological Chemistry, Molecular & Cellular Proteomics, and the Journal of Lipid Research. Discover the latest research from ASBMB here.