title: Human EZF, a Krüppel-like zinc finger protein, is expressed in vascular endothelial cells and contains transcriptional activation and repression domains.
abstract: 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.
authors.affiliation: Cardiovascular Biology Laboratory, Harvard School of Public Health, Boston, Massachusetts 02115, USA.
authors.forename: S F
authors.initials: SF
authors.lastname: Yet
authors.forename: M M
authors.initials: MM
authors.lastname: McA'Nulty
authors.forename: S C
authors.initials: SC
authors.lastname: Folta
authors.forename: H W
authors.initials: HW
authors.lastname: Yen
authors.forename: M
authors.initials: M
authors.lastname: Yoshizumi
authors.forename: C M
authors.initials: CM
authors.lastname: Hsieh
authors.forename: M D
authors.initials: MD
authors.lastname: Layne
authors.forename: M T
authors.initials: MT
authors.lastname: Chin
authors.forename: H
authors.initials: H
authors.lastname: Wang
authors.forename: M A
authors.initials: MA
authors.lastname: Perrella
authors.forename: M K
authors.initials: MK
authors.lastname: Jain
authors.forename: M E
authors.initials: ME
authors.lastname: Lee
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D019677:Artificial Gene Fusion; D002478:Cells, Cultured; D002874:Chromosome Mapping; D002899:Chromosomes, Human, Pair 9; D003001:Cloning, Molecular; D018076:DNA, Complementary; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D004730:Endothelium, Vascular / Q000378:metabolism*; D006801:Humans; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors; D051379:Mice; D008969:Molecular Sequence Data; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors; D015533:Transcriptional Activation; D014162:Transfection; D016335:Zinc Fingers
chemical_list: D018076:DNA, Complementary; D004268:DNA-Binding Proteins; C000715467:KLF4 protein, human; C000715468:Klf4 protein, mouse; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors; D014157:Transcription Factors