Structure of genes encoding chromosomal HMG1 proteins from maize

The high mobility group (HMG) proteins of the HMG1 family are architectural proteins in chromatin that are considered to facilitate the formation of c omplex nucleoprotein structures in various biological processes such as tra nscription and recombination. Plants express a variety of these non-sequenc e-specific DNA-bending proteins. The sequences encoding the maize HMGa and HMGc1 proteins were isolated from a genomic DNA library. Determination of t he nucleotide sequences of these genes revealed that the coding region of b oth genes has a similar genomic structure, comprising seven exons and six i ntrons. The positioning of the introns is conserved between the two genes, whereas the number of introns and their positions are entirely different in the related animal genes. In the 5' flanking region of the hungc1 gene, a copia-like retrotransposon was identified. In addition to the genes encodin g HMGa and HMGc1, several genomic fragments (retropseudo gene, fragments of the genes) were isolated and characterised. (C) 1999 Elsevier Science B.V. All rights reserved.