THE IKAROS GENE ENCODES A FAMILY OF LYMPHOCYTE-RESTRICTED ZINC-FINGERDNA-BINDING PROTEINS, HIGHLY CONSERVED IN HUMAN AND MOUSE

The Ikaros gene is an essential regulator in the development and homeo stasis of the mouse lymphopoietic system, To study the role of the Ika ros gene in the human lymphopoietic system, we cloned and characterize d human Ikaros cDNAs. In the human, as in the mouse, differential spli cing of Ikaros primary transcripts generates a family of lymphoid-rest ricted zinc finger DNA binding proteins, highly conserved in sequence composition and relative expression to the mouse homologues, Expressio n of Ikaros isoforms is highly restricted to the lymphopoietic system and is particularly enriched in maturing thymocytes, The Ikaros gene m aps at a syntenic locus located on the short arm of human chromosome 7 and on mouse chromosome 11 next to the epidermal growth factor recept or (Egfr), The high degree of conservation of the Ikaros gene at the g enetic and expression levels strongly suggests that it plays a fundame ntal role in the ontogeny of the lymphopoietic system across species.