Part:BBa_K203105

LDL receptor promoter (sterol regulated)

This part is a natural LDL receptor promoter responsive to SREBP and when placed upstream of other genes could induce their transcription in response to lipid addition to the medium.

Usage and Biology

Sterol regulatory element-binding protein (SREBP) is a transcription factor involved in the regulation of sterol metabolism. In cells with high concentration of cholestrol SREBP is present in an inactive form anchored to the endoplasmatic reticulum or the nuclear envelop. If the cholesterol concentration decreases SREBP is cleaved by the proteases site-1 protease and site-2 protease resulting in a release of the aminoterminal domain of SREBP. Two additional proteins (Scap and Insig) are needed to regulate this process in a way that the cleavage occurs exclusively during lack of sterol. The aminoterminal domain of SREBP is translocated into the nucleus and binds to the DNA consensus sequence TCACNCCAC. The binding causes an up regulation of the genes needed for cholesterol synthesis. See reference at [http://2009.igem.org/Team:Heidelberg/Eucaryopedia#Transcription_factors Eucaryopedia].

Sequence and Features

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  COMPATIBLE WITH RFC[12]
• 21
  COMPATIBLE WITH RFC[21]
• 23
  COMPATIBLE WITH RFC[23]
• 25
  COMPATIBLE WITH RFC[25]
• 1000
  INCOMPATIBLE WITH RFC[1000]

  Illegal BsaI.rc site found at 139
  Illegal SapI site found at 128
  

Functional Parameters

n/a	LDL receptor promoter (sterol regulated)

The natural LDL receptor promoter was induced by Lipoprotein Deficient Serum (more details: see [http://2009.igem.org/wiki/index.php?title=Team:Heidelberg/Notebook_promoters_cells&action=edit&redlink=1 Cell Culture Notebook]) in [http://2009.igem.org/Team:Heidelberg/Eucaryopedia#HeLa HeLa cells]. Promoter activtiy was then roughly characterized analogous to [http://2009.igem.org/Team:Heidelberg/Measurement REU] by TECAN (automated plate fluorescence reader). For more natural promoters look at Part:BBa_K203106 and Part:BBa_K203107.

BBa_K203105 is a natural LDL receptor promoter induced approximately 25% by Lipoprotein Deficient Serum;. The GFP flourescence of the LDL receptor promoter was measured by TECAN once (à three replicates). Background fluorescence was substracted, and fluorescence levels are plotted relative to Part:BBa_K203112.