cis-Acting Elements in the Hepatocyte Growth Factor-Like Protein Gene Regulate Kidney and Liver-Specific Expression in Mice

Abstract

Previous studies from our laboratory demonstrated that the hepatocyte-specific transcriptional activity of the hepatocyte growth factor-like protein/macrophage stimulating protein (HGFL) promoter is modulated in HepG2 cells by the first 135 base pairs (bp) upstream of the HGFL transcriptional start site. Gel mobility shift and transactivation assays demonstrated that hepatocyte nuclear factor-4 (HNF-4) binds to this region and is responsible, in part, for the liver-specific expression of this gene in HepG2 cells. In an attempt to understand the in vivo mechanism regulating the expression of HGFL, a series of transgenic mice were generated that contained four different regions upstream of the HGFL promoter attached to the coding sequences for chloramphenicol acetyltransferase (CAT). Interestingly, upstream promoter sequences, containing as little as 104 bp upstream of the translational start site, were able to drive reporter expression and protein production specifically in kidney and liver tissue. Strikingly, when the first exon and intron of the HGFL gene was inserted downstream of the 135 bp promoter element, only liver-specific expression was observed. These studies indicate that short sequences upstream of HGFL can drive efficient expression in kidney and liver tissue, and that sequences in the first intron of the HGFL gene contain regulatory elements that direct kidney-specific transcriptional repression in vivo and aid in the proper recapitulation of HGFL expression in mice.

Met‐Related Receptor Tyrosine Kinase Ron in Tumor Growth and Metastasis

“…Promoter analyses have suggested that the transcription factor hepatocyte nuclear factor-4 is important for the liver-specific expression of HGFL (Waltz et al, 1996). Specific elements in the first intron of HGFL have also been found to regulate liver-and kidney-specific expression (Wetzel et al, 2003). In addition, experiments performed in one cell type derived from large-cell lung carcinoma have demonstrated the ability of mutant p53 to associate with the HGFL promoter and repress its transcriptional activity, leading to a decrease in HGFL mRNA and secreted protein and increased cell survival after exposure to a chemotherapeutic agent (Zalcenstein et al, 2006).…”