STEROL REGULATION OF ACETYL-COENZYME-A CARBOXYLASE - A MECHANISM FOR COORDINATE CONTROL OF CELLULAR LIPID

Transcription from the housekeeping promoter for the acetyl coenzyme A carboxylase (ACC) gene, which encodes the rate-controlling enzyme of fatty acid biosynthesis, is shown to be regulated by cellular sterol l evels through novel binding sites for the sterol-sensitive sterol regu latory element binding protein (SREBP)-1 transcription factor, The pos ition of the SREBP sites relative to those for the ubiquitous auxiliar y transcription factor Sp1 is reminiscent of that previously described for the sterol-regulated low density lipoprotein receptor promoter, T he experiments provide molecular evidence that the metabolism of fatty acids and cholesterol, two different classes of essential cellular li pids, are coordinately regulated by cellular lipid levels.