Comparative analysis of promoter regions containing binding sites of the heterodimeric transcription factor Ino2/Ino4 involved in yeast phospholipid biosynthesis.
The inositol/choline responsive element (ICRE) functions as a UAS element mediating coordinate expression of structural genes required for yeast phospholipid biosynthesis. However, ICRE motifs could be detected upstream of various genes apparently not involved in lipid metabolism. In this work we investigated the expression pattern of selected genes containing ICRE promoter motifs, as identified by in silico analysis (ARG4, ERG20, FAR8, GPD2, RSF1, URA8, VHT1 and YEL073C). It turned out that the presence of an ICRE upstream of a gene of unknown function indeed allows to conclude for regulation by phospholipid precursors, which is mediated by activators Ino2/Ino4 and the repressor Opi1. We also demonstrated in vitro binding of Ino2/Ino4 heterodimers to promoter regions. Thus, our analysis supports the view that identification of regulatory elements by a database search provides evidence for a specific pattern of gene expression. Activation by pathway-specific regulators may suggest a physiological function for as yet uncharacterized genes.
Hoppen
Jens
J
Institut für Mikrobiologie, Abt. Genetik und Biochemie, Jahnstrasse 15a, D-17487 Greifswald, Germany.
Repenning
Antje
A
Albrecht
Antje
A
Geburtig
Susanne
S
Schüller
Hans-Joachim
HJ
D001483:Base Sequence; D051792:Basic Helix-Loop-Helix Proteins; D001665:Binding Sites; D019281:Dimerization; D015966:Gene Expression Regulation, Fungal; D008969:Molecular Sequence Data; D010743:Phospholipids / Q000096:biosynthesis*; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020218:Response Elements / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015534:Trans-Activators / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation
D051792:Basic Helix-Loop-Helix Proteins; D010743:Phospholipids; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators; D014157:Transcription Factors; C095723:INO2 protein, S cerevisiae; C063311:INO4 protein, S cerevisiae; C096105:OPI1 protein, S cerevisiae