Human EZF, a Krüppel-like zinc finger protein, is expressed in vascular endothelial cells and contains transcriptional activation and repression domains.

Autor: Yet, S F, McA'Nulty, M M, Folta, S C, Yen, H W, Yoshizumi, M, Hsieh, C M, Layne, M D, Chin, M T, Wang, H, Perrella, M A, Jain, M K, Lee, M E
Zdroj: Journal of Biological Chemistry; January 1998, Vol. 273 Issue: 2 p1026-31, 6p
Abstrakt: Members of the erythroid Krüppel-like factor (EKLF) multigene family contain three C-terminal zinc fingers, and they are typically expressed in a limited number of tissues. EKLF, the founding member, transactivates the beta-globin promoter by binding to the CACCC motif. EKLF is essential for expression of the beta-globin gene as demonstrated by gene deletion experiments in mice. Using a DNA probe from the zinc finger region of EKLF, we cloned a cDNA encoding a member of this family from a human vascular endothelial cell cDNA library. Sequence analysis indicated that our clone, hEZF, is the human homologue of the recently reported mouse EZF and GKLF. hEZF is a single-copy gene that maps to chromosome 9q31. By gel mobility shift analysis, purified recombinant hEZF protein bound specifically to a probe containing the CACCC core sequence. In co-transfection experiments, we found that sense but not antisense hEZF decreased the activity of a reporter plasmid containing the CACCC sequence upstream of the thymidine kinase promoter by 6-fold. In contrast, EKLF increased the activity of the reporter plasmid by 3-fold. By fusing hEZF to the DNA-binding domain of GAL4, we mapped a repression domain in hEZF to amino acids 181-388. We also found that amino acids 91-117 of hEZF confer an activation function on the GAL4 DNA-binding domain.
Databáze: Supplemental Index