tailieunhanh - Báo cáo khoa học: Ciz1, a p21Cip1/ Waf1-interacting zinc finger protein and DNA replication factor, is a novel molecular partner for human enhancer of rudimentary homolog

Enhancer of rudimentary homolog (Drosophila) (ERH) is a small, highly conserved, nuclear protein with a unique three-dimensional structure, whose gene has been identified in animals, plants and protists, but not in fungi. | ễFEBS Journal Ciz1 a p21Cip1 Waf1-interacting zinc finger protein and DNA replication factor is a novel molecular partner for human enhancer of rudimentary homolog Anna Lukasik Katarzyna A. Uniewicz Marta Kulis and Piotr Kozlowski Institute of Biochemistry University of Warsaw Poland Keywords Ciz1 DNA replication ERH human protein-protein interaction Correspondence P. Kozlowski Institute of Biochemistry University of Warsaw Miecznikowa 1 02-096 Warsaw Poland Fax 48 22 5543116 Tel 48 22 5543108 E-mail pkozlowski@ Database The nucleotide sequence reported in this paper is available from the DDBJ EMBL GenBank databases under the accession number EF441870. UniProtKB Swiss-Prot accession numbers P43243 matrin 3 P84090 ERH and Q9ULV3 Ciz1 Enhancer of rudimentary homolog Drosophila ERH is a small highly conserved nuclear protein with a unique three-dimensional structure whose gene has been identified in animals plants and protists but not in fungi. Involvement of ERH in fundamental processes such as regulation of pyrimidine metabolism cell cycle progression transcription and cell growth control has been suggested. Here employing a yeast two-hybrid system a glutathione S-transferase pull-down assay and tandem MS we demonstrate that Ciz1 is a bona fide interactor of human ERH. Ciz1 is a nuclear zinc finger protein interacting with p21Cip1 Waf1 a universal inhibitor of cyclin-dependent kinases and is a DNA replication factor. The region of Ciz1 necessary for the interaction with ERH spans residues 531-644 encompassing its first zinc finger motif. This region overlaps the p21Cip1 Waf1-binding site suggesting that the interaction with ERH could block the binding of p21Cip1 Waf1 by Ciz1 in the cell. When ERH and Ciz1 are coexpressed in HeLa cells Ciz1 recruits ERH to DNA replication foci. Received 2 October 2007 revised 9 November 2007 accepted 21 November 2007 doi Enhancer of rudimentary homolog Drosophila ERH is a small .