0 12 Differential differential JJ 13 24 interaction interaction NN 25 27 of of IN 28 35 nuclear nuclear JJ 36 43 factors factor NNS 44 48 with with IN 49 52 the the DT 53 71 leukocyte-specific leukocyte-specific JJ 72 76 pp52 pp52 NN 77 85 promoter promoter NN 86 88 in in IN 89 90 B B NNP 91 94 and and CC 95 96 T t NN 97 102 cells cell NNS 102 103 . . . 105 108 The the DT 109 127 leukocyte-specific leukocyte-specific JJ 127 128 , , , 129 149 cytoskeleton-binding cytoskeleton-binding JJ 150 154 pp52 pp52 NN 155 156 ( ( ( 156 161 LSP-1 LSP-1 NNP 161 162 , , , 163 168 WP-34 WP-34 NNP 168 169 ) ) ) 170 177 protein protein NN 178 180 is be VBZ 181 187 widely widely RB 188 197 expressed express VBN 198 200 in in IN 201 209 multiple multiple JJ 210 219 leukocyte leukocyte NN 220 228 lineages lineage NNS 228 229 , , , 230 239 including include VBG 240 241 B B NNP 242 245 and and CC 246 247 T t NN 248 259 lymphocytes lymphocyte NNS 259 260 , , , 261 273 granulocytes granulocyte NNS 273 274 , , , 275 278 and and CC 279 290 macrophages macrophage NNS 290 291 . . . 292 294 We we PRP 295 305 previously previously RB 306 314 detected detect VBD 315 316 a a DT 317 332 tissue-specific tissue-specific JJ 333 341 promoter promoter NN 342 351 preceding precede VBG 352 355 the the DT 356 360 exon exon NN 361 369 encoding encode VBG 370 373 the the DT 374 375 N N NNP 376 384 terminus terminus NN 385 387 of of IN 388 391 the the DT 392 396 pp52 pp52 NN 397 406 leukocyte leukocyte NN 407 414 protein protein NN 414 415 . . . 416 420 Here here RB 421 423 we we PRP 424 432 describe describe VBP 433 436 the the DT 437 447 functional functional JJ 448 464 characterization characterization NN 465 467 of of IN 468 472 this this DT 473 481 promoter promoter NN 482 485 and and CC 486 500 identification identification NN 501 503 of of IN 504 507 the the DT 508 515 factors factor NNS 516 518 in in IN 519 520 B B NNP 521 524 and and CC 525 526 T t NN 527 532 cells cell NNS 533 537 that that WDT 538 546 regulate regulate VBP 547 550 its its PRP$ 551 559 activity activity NN 559 560 . . . 561 564 The the DT 565 569 pp52 pp52 NN 570 578 promoter promoter NN 579 587 contains contain VBZ 588 590 an an DT 591 600 initiator initiator NN 601 611 specifying specify VBG 612 615 the the DT 616 622 unique unique JJ 623 624 5 5 CD 624 625 ’ ' SYM 626 634 terminus terminus NN 635 637 of of IN 638 642 pp52 pp52 NN 643 647 mRNA mrna NN 647 648 , , , 649 655 tandem tandem JJ 656 661 pairs pair NNS 662 664 of of IN 665 668 Ets ets NN 669 672 and and CC 673 676 SP1 sp1 NN 677 683 motifs motif NNS 683 684 , , , 685 688 and and CC 689 690 a a DT 691 695 lone lone JJ 696 701 C/EBP C/EBP NNP 702 707 motif motif NN 707 708 . . . 709 712 All all PDT 713 718 these these DT 719 725 motifs motif NNS 726 729 are be VBP 730 739 essential essential JJ 740 743 and and CC 744 756 collectively collectively RB 757 764 control control VBP 765 780 transcriptional transcriptional JJ 781 789 activity activity NN 789 790 . . . 791 794 DNA DNA NNP 795 802 binding binding NN 803 810 studies study NNS 811 814 and and CC 815 817 Ab Ab NNP 818 828 supershift supershift NN 829 835 assays assay NNS 836 844 revealed reveal VBD 845 849 that that IN 850 859 different different JJ 860 872 combinations combination NNS 873 875 of of IN 876 883 factors factor NNS 884 892 interact interact VBP 893 897 with with IN 898 903 these these DT 904 910 motifs motif NNS 911 913 in in IN 914 915 B B NNP 916 921 cells cell NNS 922 924 vs vs CC 925 926 T t NN 927 932 cells cell NNS 932 933 . . . 934 937 The the DT 938 941 Ets Ets NNP 942 948 motifs motif NNS 949 952 are be VBP 953 967 preferentially preferentially RB 968 973 bound bind VBN 974 976 by by IN 977 981 PU-1 pu-1 NN 982 984 in in IN 985 986 B B NNP 987 991 cell cell NN 992 1000 extracts extract NNS 1001 1005 from from IN 1006 1009 all all DT 1010 1016 stages stage NNS 1017 1019 of of IN 1020 1031 development development NN 1031 1032 , , , 1033 1040 whereas whereas IN 1041 1042 a a DT 1043 1052 different different JJ 1053 1056 Ets Ets NNP 1057 1063 family family NN 1064 1070 member member NN 1071 1077 reacts react VBZ 1078 1082 with with IN 1083 1088 these these DT 1089 1095 motifs motif NNS 1096 1098 in in IN 1099 1100 T t NN 1101 1105 cell cell NN 1106 1114 extracts extract NNS 1114 1115 . . . 1116 1119 The the DT 1120 1125 C/EBP C/EBP NNP 1126 1131 motif motif NN 1132 1134 is be VBZ 1135 1140 bound bind VBN 1141 1143 by by IN 1144 1152 Ig/EBP-1 ig/ebp-1 NN 1153 1155 in in IN 1156 1161 pre-B pre-b JJ 1162 1166 cell cell NN 1167 1170 and and CC 1171 1172 T t NN 1173 1177 cell cell NN 1178 1186 extracts extract NNS 1186 1187 , , , 1188 1191 but but CC 1192 1194 is be VBZ 1195 1203 replaced replace VBN 1204 1206 by by IN 1207 1214 nuclear nuclear JJ 1215 1230 factor-IL-6beta factor-il-6beta NN 1231 1233 or or CC 1234 1235 a a DT 1236 1243 nuclear nuclear JJ 1244 1268 factor-IL-6beta-Ig/EBP-1 factor-il-6beta-ig/ebp-1 NN 1269 1280 heterodimer heterodimer NN 1281 1283 in in IN 1284 1296 plasmacytoma plasmacytoma NN 1297 1301 cell cell NN 1302 1310 extracts extract NNS 1310 1311 . . . 1312 1319 Despite despite IN 1320 1323 its its PRP$ 1324 1332 reported report VBN 1333 1337 role role NN 1338 1340 as as IN 1341 1342 a a DT 1343 1351 negative negative JJ 1352 1361 regulator regulator NN 1362 1364 of of IN 1365 1378 transcription transcription NN 1378 1379 , , , 1380 1388 Ig/EBP-1 ig/ebp-1 NN 1389 1396 appears appear VBZ 1397 1399 to to TO 1400 1405 exert exert VB 1406 1407 a a DT 1408 1419 stimulatory stimulatory JJ 1420 1426 effect effect NN 1427 1429 on on IN 1430 1434 this this DT 1435 1443 promoter promoter NN 1443 1444 . . . 1445 1450 These these DT 1451 1459 findings finding NNS 1460 1466 reveal reveal VBP 1467 1470 the the DT 1471 1479 features feature NNS 1480 1491 controlling control VBG 1492 1495 the the DT 1496 1500 pp52 pp52 NN 1501 1509 promoter promoter NN 1510 1512 in in IN 1513 1514 B B NNP 1515 1518 and and CC 1519 1520 T t NN 1521 1526 cells cell NNS 1527 1530 and and CC 1531 1538 provide provide VBP 1539 1542 the the DT 1543 1553 foundation foundation NN 1554 1557 for for IN 1558 1569 determining determine VBG 1570 1573 the the DT 1574 1584 regulation regulation NN 1585 1587 of of IN 1588 1592 this this DT 1593 1601 promoter promoter NN 1602 1604 in in IN 1605 1610 other other JJ 1611 1620 leukocyte leukocyte NN 1621 1629 lineages lineage NNS 1629 1630 . . .