STRUCTURAL ORGANIZATION OF THE RAE28 GENE, A PUTATIVE MURINE HOMOLOG OF THE DROSOPHILA POLYHOMEOTIC GENE

A putative murine homologue of the Drosophila polyhomeotic gene, named rae28, has been isolated from a genomic library of 129/SV mouse and i ts structural organization has been analyzed, rae28 is a single gene o f approximately 22 kb long and consists of 15 exons. Its 5'-flanking r egion lacks typical transcriptional regulatory sequences, such as TATA and CCAAT boxes, but contains GC-rich sequences and seven putative bi nding sites for a transcription factor, Sp1. One major transcription s tart point has been determined. The overall exon-intron organization s uggested that three different Rae28 mRNAs are generated through altern ative splicing, Furthermore, the rae28 gene has been located on the R- positive F3 band of mouse chromosome 6 by the direct R-banding fluores cence in situ hybridization methods.