ZBP-89, a Krueppel-like zinc finger protein, inhibits epidermal growth factor induction of the gastrin promoter

• Published in: Molecular and cellular biology 1996-01, Vol.16 (12), p.6644-6653
• Main Authors: Merchant, J L, Iyer, G R, Taylor, B R, Kitchen, J R, Mortensen, E R, Wang, Ziyuan, Flintoft, R J, Michel, J B, Bassel-Duby, R
• Format: Article
• Language: English
• ISSN: 0270-7306

We have shown previously that a GC-rich element (GGGGCGGGGTGGGGGG) conferring epidermal growth factor (EGF) responsiveness to the human gastrin promoter binds Sp1 and additional undefined complexes. A rat GH sub(4) cell line expression library was screened by using a multimer of the gastrin EGF response element, and three overlapping cDNA clones were identified. The full-length rat cDNA encoded an 89-kDa zinc finger protein (ZBP-89) that was 89% identical to a 49-kDa human factor, ht beta , that binds a GTGGG/CACCC element in T-cell receptor promoters. The conservation of amino acids between the zinc fingers indicates that ZBP-89 is a member of the C sub(2)H sub(2) zinc finger family subclass typified by the Drosophila Krueppel protein. ZBP-89 is ubiquitously expressed in normal adult tissues. It binds specifically to the gastrin EGF response element and inhibits EGF induction of the gastrin promoter. Collectively, these results demonstrate that ZBP-89 functions as a repressor of basal and inducible expression of the gastrin gene.