AI608257, bHLHd2, Class D basic helix-loop-helix protein 2, OTTHUMP00000028740, Processed sterol regulatory element-binding protein 2, SRBP2_HUMAN, SREBF 2, Srebf2, SREBF2 protein, SREBP 2, SREBP2, SREBP2gc, sterol regulatory element binding factor 2, Sterol regulatory element binding transcription
The low density lipoprotein (LDL) receptor mediates the endocytic uptake of cholesterol-carrying lipoproteins, thereby controlling cholesterol levels in cells and plasma. Transcription of the LDL receptor gene is controlled by a ten base pair sequence in the 5 flanking region, designated sterol regulatory element 1 (SRE-1). When cellular sterol stores are depleted, the element is activated, the gene is transcribed and the cellular uptake of LDL increases. A set of SREbinding proteins (SREBPs) have been identified, including two basic helixloop-helix-leucine zipper (bHLH-zip) transcription factors, designated SREBP-1 and SREBP-2. SREBP-1 and SREBP-2 have been shown to have the same specificity for SRE-1 in vitro and to activate the transcription of reporter genes containing SRE-1 in the same way.