Transcriptional activation of yeast nucleotide biosynthetic gene ADE4 by GCN4.

H.U Mösch,B Scheier,R Lahti,P Mäntsäla,G.H Braus

doi:10.1016/s0021-9258(18)54945-0

Abstract

The yeast transcriptional regulator protein GCN4 harbors the bZIP DNA binding motif, which is common to a family of DNA-binding proteins in eukaryotic organisms from yeast to man. GCN4 and the mammalian activator protein AP-1 (jun/fos) regulate transcription by binding the same consensus DNA sequence ATGA (C/G)TCAT. GCN4 positively regulates the production of precursors of protein synthesis in yeast cells in response to the environmental signal "amino acid starvation." We find three GCN4 responsive elements (GCREs) in the 5'-flanking region of the purine biosynthetic gene ADE4 and demonstrate that GCN4 efficiently activates transcription of ADE4. Two GCREs are essential to synergistically activate ADE4 transcription by binding GCN4. The distal GCRE1 is also required for basal transcription of ADE4. Therefore, transcription factor GCN4 affects, in addition to protein biosynthesis, also nucleotide biosynthesis and, comparable to its mammalian counterpart AP-1, has a more general function within the yeast cell than previously assumed.

Highlights

The yeast transcriptional regulator protein GCN4 acid biosynthetic pathways and two tRNA synthetase genes harbors the bZIP DNAbinding motif, whichis common (Hinnebusch, 1988; Mirande and Waller 1988)
Fragment of985 bp containing the regulatory region of the ADE4 gene with a portion of its structural gene was isolated from plasmid pPM7 (Mantsala and Zalkin, 1984) and, after trimming its 5’ ends blunt using Klenow polymerase, inserted into the SmaIcleavage site of plasmid M13mplO (Vieira and Messing, 1982).Nucleotide sequencing was performed with the chain termination method (Sanger et al, 1977)
GCN4 binds to the GCN4 responsive element (GCRE),‘ that has been well characterized as the palindromic sequence 5’ ATGA(C/G)TCAT

Summary

Introduction

The yeast transcriptional regulator protein GCN4 acid biosynthetic pathways and two tRNA synthetase genes harbors the bZIP DNAbinding motif, whichis common (Hinnebusch, 1988; Mirande and Waller 1988). This sequence yeast strains carrying ADE4 mutant alleles were constructed using has been shown to be an optimal binding site for the the gene replacement technique (Rudolph et al, 1985).The complete human trans-activator protein complex AP-1 (Bohmann et al, 1987) and been referred toas ARE, AP-1 responsive element, or TRE, 12-0-tetradecanoylphorbol-13-acetateresponsive element, respectively (Kouzarides and Ziff, 1989).

Results

Conclusion