| Ets 1 and Ets 2 , but not Elf 1 , cooperate with GATA 3 and HTLV 1 Tax 1 . ^^^ In myeloid Kasumi cells , Ets 1 and Ets 2 failed to stimulate IL 5 promoter activity , unless the T cell specific transcription factor GATA 3 was added . ^^^ These results show , for the first time , that Ets 1 and Ets 2 are able to cooperate with GATA 3 . ^^^ Both ionomycin and Tax 1 increased the combined effect of GATA 3 with Ets 1 and Ets 2 in the presence of PMA . ^^^ The synergism of GATA 3 with either Ets 1 or Ets 2 may play an important role in calcium or Tax 1 dependent regulation of IL 5 expression in Th 2 cells or in HTLV 1 transformed adult T cell leukemia cells , respectively . . ^^^ |