Regulation of lactase-phlorizin hydrolase gene expression by the caudal-related homoeodomain protein Cdx-2.
Lactase-phlorizin hydrolase is exclusively expressed in the small intestine and is often used as a marker for the differentiation of enterocytes. The cis-element CE-LPH1 found in the lactase-phlorizin hydrolase promoter has previously been shown to bind an intestinal-specific nuclear factor. By electrophoretic mobility-shift assay it was shown that the factor Cdx-2 (a homoeodomain-protein related to caudal) binds to a TTTAC sequence in the CE-LPH1. Furthermore it was demonstrated that Cdx-2 is able to activate reporter gene transcription by binding to CE-LPH1. A mutation in CE-LPH1, which does not affect Cdx-2 binding, results in a higher transcriptional activity, indicating that the CE-LPH1 site contains other binding site(s) in addition to the Cdx-2-binding site.
Troelsen
J T
JT
Department of Medical Biochemistry and Genetics, Biochemical Laboratory C, The Panum Institute, University of Copenhagen, DK-2200 Copenhagen N, Denmark.
Mitchelmore
C
C
Spodsberg
N
N
Jensen
A M
AM
Norén
O
O
Sjöström
H
H
D001483:Base Sequence; D000071616:CDX2 Transcription Factor; D018938:Caco-2 Cells; D015971:Gene Expression Regulation, Enzymologic; D006367:HeLa Cells; D018398:Homeodomain Proteins / Q000235:genetics*; D006801:Humans; D010694:Lactase-Phlorizin Hydrolase / Q000096:biosynthesis / Q000235:genetics*; D008969:Molecular Sequence Data; D015534:Trans-Activators
D000071616:CDX2 Transcription Factor; D018398:Homeodomain Proteins; D015534:Trans-Activators; D010694:Lactase-Phlorizin Hydrolase