Expression of tinScer\UAS.cYa, driven by Scer\GAL4tin.cBa, results in the rescue of few additional cardioblasts in a Df(3L)DocA background. Coexpression of pnrScer\UAS.cHa and tinScer\UAS.cYa, under the control of Scer\GAL4tin.cBa, induces the formation of more cardioblasts than expression of pnrScer\UAS.cHa alone. When Doc2Scer\UAS.cRa is coexpressed with only tinScer\UAS.cYa, or pnrScer\UAS.cHa and tinScer\UAS.cYa together, large numbers of extra cardioblasts are formed. Expression of all three transgenes results in double the amount of cardioblasts compared to wild type. Coexpression of Doc2Scer\UAS.cRa, tinScer\UAS.cYa, and pnrScer\UAS.cHa, under the control of Scer\GAL4twi.2PE, causes widespread ectopic cardioblast formation to a much greater extent than expression of Doc2Scer\UAS.cRa alone or in combination with tinScer\UAS.cYa plus pnrScer\UAS.cHa.