These data demonstrate that PAX3 and PAX3-FKHR contain structurally distinct transcriptional activation domains and suggest that a consequent difference in function is important for oncogenesis..     ///    Recently we demonstrated that PAX3-FKHR is a more potent transcriptional activator than PAX3 despite impaired binding to canonical PAX3 binding sites.     ///    "To compare the PAX3 and putative PAX3-FKHR transactivation domains, we fused C-terminal test fragments to the heterologous GAL4 DNA-binding domain and tested activation of a reporter gene co-transfected into four cell types. "    ///    "Wild type PAX3 protein and the PAX3-FKHR fusion protein of alveolar rhabdomyosarcoma contain potent, structurally distinct transcriptional activation domains.. "    ///    "ARMS cells express a PAX3-FKHR fusion protein containing the complete N-terminal, DNA-binding domain of PAX3 and the C-terminus of FKHR. "