Identification of human and mouse HIRA-interacting protein-5 (HIRIP5), twomammalian representatives in a family of phylogenetically conserved proteins with a role in the biogenesis of Fe/S proteins

The human HIRA protein is encoded from a region of chromosome 22q that is c ritical for the DiGeorge syndrome and the velocardiofacial syndrome. We hav e previously reported that it directly interacts with core histones, with a novel histone-binding protein, HIRIP3, and during mouse embryogenesis, wit h the developmentally regulated homeodomain protein Pax3. suggesting a prom oter-targeted function at the chromatin level. We here report on HIRA-inter acting protein 5 (HIRIP5), a small acidic protein that interacted with HIRA in a double-hybrid screen performed in yeast and in in vitro protein inter action experiments. HIRIP5 has highly conserved homologs in both prokaryote s and eukaryotes, including the NFUI gene product which has been implicated in iron metabolism in mitochondria of the yeast Saccharomyces cerevisiae. By radioactive in situ hybridization, the HIRIP5 gene was mapped to the 2p1 3-p15 chromosomal region, separate from any region previously associated wi th DiGeorge syndrome. (C) 2001 Elsevier Science B.V. All rights reserved.