Saccharomyces cerevisiae Adr1p governs fatty acid beta-oxidation and peroxisome proliferation by regulating POX1 and PEX11

Saccharomyces cerevisiae Adr1p is essential for fatty acid degradation and peroxisome proliferation. Here, the role of Adr1p was examined with respect to the transcriptional regulation of the Pip2p-Oaf1p dependent genes POX1 and PEX11. POX1 encodes the rate-limiting enzyme of peroxisomal beta -oxida tion, acyl-CoA oxidase. The POX1 promoter was shown to contain a canonical Adr1p element (UAS1), within which the oleate response element (ORE) was ne sted. PEX11 codes for a peroxin that is critical for normal peroxisome prol iferation, and its promoter was shown similarly to contain a UAS1-like elem ent overlapping the ORE. Northern analysis demonstrated that transcriptiona l up-regulation of both POX1 and PEX11 was abolished in adr1 Delta mutant c ells, and immunoblotting confirmed that the abundance of their gene product s was dramatically reduced. Studies of an overlapping ORE/UAS1 arrangement in the CTA1 promoter revealed synergy between these elements. We conclude t hat overlapping ORE and UAS1 elements in conjunction with their binding fac tors Pip2p-Oaf1p and Adr1p coordinate the carbon flux through beta -oxidati on with peroxisome proliferation.