0 10 Regulation regulation NN 11 13 of of IN 14 17 the the DT 18 32 megakaryocytic megakaryocytic JJ 33 45 glycoprotein glycoprotein NN 46 48 IX ix CD 49 57 promoter promoter NN 58 60 by by IN 61 64 the the DT 65 74 oncogenic oncogenic JJ 75 78 Ets Ets NNP 79 92 transcription transcription NN 93 99 factor factor NN 100 105 Fli-1 fli-1 NN 105 106 . . . 108 120 Glycoprotein Glycoprotein NNP 121 122 ( ( ( 122 124 GP GP NNP 124 125 ) ) ) 126 128 IX ix CD 129 131 is be VBZ 132 133 a a DT 134 141 subunit subunit NN 142 144 of of IN 145 148 the the DT 149 152 von von NNP 153 163 Willebrand Willebrand NNP 164 172 receptor receptor NN 172 173 , , , 174 183 GPIb-V-IX GPIb-V-IX NNP 183 184 , , , 185 190 which which WDT 191 199 mediates mediate VBZ 200 208 adhesion adhesion NN 209 211 of of IN 212 221 platelets platelet NNS 222 224 to to TO 225 228 the the DT 229 243 subendothelium subendothelium NN 244 246 of of IN 247 254 damaged damage VBN 255 260 blood blood NN 261 268 vessels vessel NNS 268 269 . . . 270 278 Previous previous JJ 279 295 characterization characterization NN 296 298 of of IN 299 302 the the DT 303 307 GPIX GPIX NNP 308 316 promoter promoter NN 317 327 identified identify VBD 328 329 a a DT 330 340 functional functional JJ 341 344 Ets ets NN 345 349 site site NN 350 354 that that WDT 354 355 , , , 356 360 when when WRB 361 370 disrupted disrupt VBN 370 371 , , , 372 379 reduced reduce VBN 380 388 promoter promoter NN 389 397 activity activity NN 397 398 . . . 399 406 However however RB 406 407 , , , 408 411 the the DT 412 415 Ets Ets NNP 416 426 protein(s) protein(s) NN 427 431 that that WDT 432 441 regulated regulate VBD 442 446 GPIX GPIX NNP 447 455 promoter promoter NN 456 466 expression expression NN 467 470 was be VBD 471 478 unknown unknown JJ 478 479 . . . 480 482 In in IN 483 487 this this DT 488 493 study study NN 493 494 , , , 495 504 transient transient JJ 505 519 cotransfection cotransfection NN 520 522 of of IN 523 530 several several JJ 531 535 GPIX GPIX NNP 536 553 promoter/reporter promoter/reporter NN 554 564 constructs construct NNS 565 569 into into IN 570 574 293T 293t NN 575 581 kidney kidney NN 582 593 fibroblasts fibroblast NNS 594 598 with with IN 599 600 a a DT 601 606 Fli-1 fli-1 NN 607 617 expression expression NN 618 624 vector vector NN 625 630 shows show VBZ 631 635 that that IN 636 639 the the DT 640 649 oncogenic oncogenic JJ 650 657 protein protein NN 658 663 Fli-1 fli-1 NN 664 667 can can MD 668 681 transactivate transactivate VB 682 685 the the DT 686 690 GPIX GPIX NNP 691 699 promoter promoter NN 700 704 when when WRB 705 707 an an DT 708 714 intact intact JJ 715 719 GPIX GPIX NNP 720 723 Ets Ets NNP 724 728 site site NN 729 731 is be VBZ 732 739 present present JJ 739 740 . . . 741 743 In in IN 744 752 addition addition NN 752 753 , , , 754 759 Fli-1 fli-1 NN 760 767 binding binding NN 768 770 of of IN 771 774 the the DT 775 779 GPIX GPIX NNP 780 783 Ets Ets NNP 784 788 site site NN 789 792 was be VBD 793 803 identified identify VBN 804 806 in in IN 807 815 antibody antibody NN 816 826 supershift supershift NN 827 838 experiments experiment NNS 839 841 in in IN 842 849 nuclear nuclear JJ 850 858 extracts extract NNS 859 866 derived derive VBN 867 871 from from IN 872 885 hematopoietic hematopoietic JJ 886 891 human human JJ 892 907 erythroleukemia erythroleukemia NN 908 913 cells cell NNS 913 914 . . . 915 926 Comparative comparative JJ 927 934 studies study NNS 935 941 showed show VBD 942 946 that that IN 947 952 Fli-1 fli-1 NN 953 956 was be VBD 957 961 also also RB 962 966 able able JJ 967 969 to to TO 970 983 transactivate transactivate VB 984 987 the the DT 988 997 GPIbalpha GPIbalpha NNP 998 1001 and and CC 1001 1002 , , , 1003 1005 to to TO 1006 1007 a a DT 1008 1014 lesser less JJR 1015 1021 extent extent NN 1021 1022 , , , 1023 1026 the the DT 1027 1032 GPIIb GPIIb NNP 1033 1041 promoter promoter NN 1041 1042 . . . 1043 1053 Immunoblot Immunoblot NNP 1054 1062 analysis analysis NN 1063 1073 identified identify VBD 1074 1079 Fli-1 fli-1 NN 1080 1087 protein protein NN 1088 1090 in in IN 1091 1098 lysates lysate NNS 1099 1106 derived derive VBN 1107 1111 from from IN 1112 1121 platelets platelet NNS 1121 1122 . . . 1123 1125 In in IN 1126 1134 addition addition NN 1134 1135 , , , 1136 1146 expression expression NN 1147 1149 of of IN 1150 1155 Fli-1 Fli-1 NNP 1156 1159 was be VBD 1160 1170 identified identify VBN 1171 1192 immunohistochemically immunohistochemically RB 1193 1195 in in IN 1196 1210 megakaryocytes megakaryocyte NNS 1211 1218 derived derive VBN 1219 1223 from from IN 1224 1231 CD34(+) cd34(+) JJ 1232 1237 cells cell NNS 1238 1245 treated treat VBN 1246 1250 with with IN 1251 1254 the the DT 1255 1268 megakaryocyte megakaryocyte NN 1269 1284 differentiation differentiation NN 1285 1288 and and CC 1289 1302 proliferation proliferation NN 1303 1309 factor factor NN 1309 1310 , , , 1311 1325 thrombopoietin thrombopoietin NN 1325 1326 . . . 1327 1332 These these DT 1333 1340 results result NNS 1341 1348 suggest suggest VBP 1349 1353 that that IN 1354 1359 Fli-1 fli-1 NN 1360 1362 is be VBZ 1363 1369 likely likely JJ 1370 1372 to to TO 1373 1381 regulate regulate VB 1382 1398 lineage-specific lineage-specific JJ 1399 1404 genes gene NNS 1405 1411 during during IN 1412 1432 megakaryocytopoiesis megakaryocytopoiesis NN 1432 1433 . . .