of proteins including B-Myc, L-Myc, N-Myc, and s-Myc. c-Myc is a b-HLH-LZ (basic helix-loop-helix-leucine zipper) protein that must form a heterodimer with another b-HLH-LZ protein, Max , in order to bind DNA and activate transcription . Mutations in myc proteins or overexpression of their encoding genes have been linked to several