Reciprocal regulation of the human sterol regulatory element binding protein (SREBP)-1a promoter by Sp1 and EGR-1 transcription factors

FERNÁNDEZ ALVAREZ, ANA JULIA; TUR, GEMMA; LÓPEZ-RODAS, GERARDO; CASADO, MARTA

FEBS LETTERS

ELSEVIER SCIENCE BV

Año: 2008 vol. 582 p. 177 - 184

0014-5793

Sterol regulatory element binding protein (SREBP)-1a is a transcription factor that is highly expressed in actively growing cells, and is involved in the biosynthesis of cholesterol, fatty acids and phospholipids. We have mapped the minimal human SREBP-1a promoter region to 75bp upstream of the translation start site where we discovered a functional role for the 3 GC-boxes containing overlapping sites for the Sp1 and EGR-1 transcription factors. Intact SP1-binding sites are essential for promoter activity, whereas EGR-1 suppresses the transcription of the human SREBP-1a promoter. These results reveal a novel physiologically relevant transcriptional mechanism for the reciprocal regulation of the SREBP-1a expression.