Binding characteristics and regulatory mechanisms of the transcription factors controlling oleate-responsive genes in Saccharomyces cerevisiae.
Transcriptional activation of many genes involved in peroxisome-related functions is regulated by the Oaf1p, Pip2p, and Adr1p transcription factors in Saccharomyces cerevisiae. We have analyzed the in vivo binding characteristics of Oaf1p-Pip2p and found that this complex is recruited to its target oleate-response element (ORE) under all growth conditions tested. In addition, this complex also binds to ORE-containing genes that do not appear to be regulated by these proteins, as well as to some genes lacking conventional OREs. The recruitment of the Oaf1p-Pip2p complex was greatly increased upon glucose derepression, possibly due to Oaf1p phosphorylation with only moderate increases upon oleate induction. Thus, this complex may receive a nutritional cue while it is already bound to DNA, suggesting that, in addition to the increase in Oaf1p-Pip2p binding, other mechanism(s) such as enhanced Adr1p association may drive the expression of highly inducible fatty acid-responsive genes. Adr1p binds to target genes in an oleate-dependent fashion and is involved in Oaf1p-Pip2p binding. In turn, the Oaf1p-Pip2p complex appears to be important for Adr1p binding to a subset of oleate-responsive genes. Adr1p is a positive regulator of ORE-containing genes, but it also acts as a negative factor in expression of some of these genes. Finally, we have also shown that Adr1p is directly involved in mediating oleate induction of Oaf1p-Pip2p target genes.
Karpichev
Igor V
IV
Department of Biology, City College of the City University of New York, New York, New York 10031, USA.
Durand-Heredia
Jorge M
JM
Luo
Yi
Y
Small
Gillian M
GM
D000123:Acetyltransferases / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D000939:Epitopes / Q000737:chemistry; D005227:Fatty Acids / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D008954:Models, Biological; D019301:Oleic Acid / Q000378:metabolism; D010766:Phosphorylation; D011485:Protein Binding; D020218:Response Elements; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic
C074682:ADR1 protein, S cerevisiae; D004268:DNA-Binding Proteins; D000939:Epitopes; D005227:Fatty Acids; C120764:OAF1 protein, S cerevisiae; C100530:PIP2 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D019301:Oleic Acid; D000123:Acetyltransferases; C061313:protein N-terminal acetyltransferase