The retroviral oncogene v-myb is a mutated and truncated version of the c-myb proto-oncogene and encodes a transcription factor (v-Myb) that specifically transforms myelomonocytic cells. v-Myb is thought to transform myelomonocytic cells by affecting the expression of specific target genes, most of which as yet remain unknown. To identify novel v-Myb regulated genes we have employed 'differential display', using a myelomonocytic chicken cell line that expresses a conditional version of v-Myb. Here we describe the identification of the gene encoding the A2b adenosine receptor, a member of the seven transmembrane receptor superfamily, as a v-Myb target gene. Our results provide the first evidence that v-Myb directly regulates a gene encoding a membrane receptor and establish a link between Myb function and adenosine receptor signaling.