The gene for the human architectural transcription factor HMGI-C consists ofn five exons each coding for a distinct functional element

Abstract

The gene on chromosome 12 coding for the human protein HMGI-C has been cloned and partially sequenced. It consists of five exons, the first and last of which include long untranslated regions. The 5′ UTR Includes a (CA/T)n tract and a polymorphic (CT)n tract. Exons II, III and IV (87,51 and 33 bp) are dispersed over →30 kb. Exons Mil separately encode the three basic DNA binding domains (‘A-T hooks’), exon IV encodes an 11 amino acid sequence characteristic of HMGI-C and absent from the human HMGI(Y) gene [Friedmann. M., Holth.L.T, Zoghbi,H.Y. and Reeves.R. (1993) Nucleic Acids Res., 21, 4259-1267], whilst exon V encodes the acidic C-terminal domain, which is subject to multiple phosphorylation. The HMGI-C gene is thus a striking example of the separation of functional protein elements into different coding exons.