GAL4 is regulated by a glucose-responsive functional domain

G. Stone, I. Sadowski

Research output: Contribution to journalArticle

48 Scopus citations

Abstract

The Saccharomyces cerevisiae transcriptional activator GAL4 is regulated by the presence of available carbon sources. Galactose induces activity by inhibiting the negative regulator GAL80, while glucose, the preferred carbon source, antagonizes GAL4 function by several mechanisms. In the present study we present evidence that one mechanism for inhibition of GAL transcription In glucose involves direct inhibition of the GAL4 protein. We demonstrate that a large, previously uncharacterized, central region of GAL4 contains at least three 'inhibitory domains' and a 'glucose response domain' (GRD). Deletion of the entire central region eliminates direct inhibition of GAL4 by glucose, and furthermore, fusion of the central region to a heterologous transcriptional activator confers inhibition by glucose. The central region inhibitory domains constitutively inhibit transcriptional activation when the GRD is absent. Direct inhibition of GAL4 activity can be detected within 30 min following glucose addition and may represent an early mechanism promoting a switch from galactose to glucose utilization. A model for the regulatory role of the central region is presented, involving interaction with an additional protein that inhibits GAL4 activity when glucose is present.

Original languageEnglish (US)
Pages (from-to)1375-1385
Number of pages11
JournalEMBO Journal
Volume12
Issue number4
StatePublished - Jan 1 1993

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Keywords

  • GAL4
  • Glucose repression
  • Saccharomyces cerevisiae
  • Transcription factor

ASJC Scopus subject areas

  • Cell Biology
  • Genetics

Cite this

Stone, G., & Sadowski, I. (1993). GAL4 is regulated by a glucose-responsive functional domain. EMBO Journal, 12(4), 1375-1385.