Misexpression of Dach2 and Eya2, and Eya2 and Six1 in somite explant culture results in synergistic regulation of Pax3 and myogenic marker genes. (A) Misexpression of Dach2 and Eya2 in somite explant culture. (Lane 1) Somites cultured with RCAS(A) Dach2 alone; (lanes 2,4) somites cultured with RCAS(A) Dach2 and RCAS(B) Eya2; (lane 3) somites cultured with RCAS(B) Eya2 alone. Cultures analyzed by RT–PCR for GAPDH, Pax3, MyoD, Myogenin, and MHC. (B) Misexpression of Eya2 and Six1 in somite explant culture. (Lane 1) Somites cultured with RCAS(B) Eya2 alone; (lanes 2,4) somites cultured with RCAS(B) Eya2 and RCAS(A) Six1; (lane 3) somites cultured with RCAS(A) Six1 alone. Cultures analyzed by RT–PCR for GAPDH, Pax3, MyoD, Myogenin, and MHC. (+) The addition of a retrovirus to the culture.