Identification and validation of candidate Myb target genes

While a considerable number of candidate Myb target genes have been reporte d to date, most of these are likely to play little or no role in transforma tion by myb oncogenes. Here we have used a conditionally myb-transformed my eloid cell line (ERMYB) to further examine Myb regulation of one candidate target gene-c-myc-that has the potential to affect cell proliferation. It w as found that the major influence on c-myc expression was the presence of c ytokine (GM-CSF) rather than Myb activity. We also describe the application of PCR-based subtractive hybridization and low-density cDNA array screenin g, in conjunction with the ERMYB line, to the identification of additional Myb target genes. Preliminary identification of a number of candidates is r eported; these include myeloperoxidase, which is known to have essential My b-binding sites in its regulatory region. (C) 2001 Academic Press.