Wenger, R H; Kvietikova, I; Rolfs, A; Camenisch, G; Gassmann, M (1998). Oxygen-regulated erythropoietin gene expression is dependent on a CpG methylation-free hypoxia-inducible factor-1 DNA-binding site. FEBS Journal, 253(3):771-777.
Full text not available from this repository.
View at publisher
The hypoxia-inducible factor-1 (HIF-1) is a transcriptional activator involved in the expression of oxygen-regulated genes such as that for erythropoietin. Following exposure to low oxygen partial pressure (hypoxia), HIF-1 binds to an hypoxia-response element located 3' to the erythropoietin gene and confers activation of erythropoietin expression. The conserved core HIF-1 binding site (HBS) of the erythropoietin 3' enhancer (CGTG) contains a CpG dinucleotide known to be a potential target of cytosine methylation. We found that methylation of the HBS abolishes HIF-1 DNA binding as well as hypoxic reporter gene activation, suggesting that a methylation-free HBS is mandatory for HIF-1 function. The in vivo methylation pattern of the erythropoietin 3' HBS in various human cell lines and mouse organs was assessed by genomic Southern blotting using a methylation-sensitive restriction enzyme. Whereas this site was essentially methylation-free in the erythropoietin-producing cell line Hep3B, a direct correlation between erythropoietin protein expression and the degree of erythropoietin 3' HBS methylation was found in different HepG2 sublines. However, the finding that this site is partially methylation-free in human cell lines and mouse tissues that do not express erythropoietin suggests that there might be a general selective pressure to keep this site methylation-free, independent of erythropoietin expression.
|Item Type:||Journal Article, refereed|
|Communities & Collections:||04 Faculty of Medicine > Institute of Physiology
07 Faculty of Science > Institute of Physiology
|DDC:||570 Life sciences; biology|
|Deposited On:||11 Feb 2008 12:23|
|Last Modified:||27 Nov 2013 22:00|
Users (please log in): suggest update or correction for this item
Repository Staff Only: item control page