0 15 Tax-independent tax-independent JJ 16 23 binding binding NN 24 26 of of IN 27 35 multiple multiple JJ 36 44 cellular cellular JJ 45 52 factors factor NNS 53 55 to to TO 56 68 Tax-response tax-response JJ 69 76 element element NN 77 80 DNA dna NN 81 83 of of IN 84 90 HTLV-I HTLV-I NNP 90 91 . . . 93 96 The the DT 97 102 human human JJ 103 109 T-cell t-cell NN 110 118 leukemia leukemia NN 119 124 virus virus NN 125 129 type type NN 130 131 I i CD 132 133 ( ( ( 133 139 HTLV-I HTLV-I NNP 139 140 ) ) ) 141 149 promoter promoter NN 150 158 contains contain VBZ 159 164 three three CD 165 171 copies copy NNS 172 174 of of IN 175 184 imperfect imperfect JJ 185 192 repeats repeat NNS 193 195 of of IN 196 197 a a DT 198 205 21-base 21-base JJ 206 210 pair pair NN 211 219 sequence sequence NN 220 230 designated designate VBN 231 235 here here RB 236 238 as as IN 239 242 TRE TRE NNP 243 244 ( ( ( 244 256 Tax-response tax-response JJ 257 264 element element NN 264 265 ) ) ) 266 270 that that WDT 271 273 is be VBZ 274 284 responsive responsive JJ 285 287 to to TO 288 291 the the DT 292 299 virally virally RB 300 307 encoded encode VBN 308 322 transactivator transactivator NN 323 330 protein protein NN 331 334 Tax tax NN 334 335 . . . 336 338 We we PRP 339 343 have have VBP 344 354 identified identify VBN 355 358 and and CC 359 368 separated separate VBN 369 373 four four CD 374 381 nuclear nuclear JJ 382 390 proteins protein NNS 391 395 from from IN 396 405 C81-66-45 C81-66-45 NNP 406 411 cells cell NNS 411 412 , , , 413 415 an an DT 416 422 HTLV-I HTLV-I NNP 423 435 immortalized immortalize VBD 436 450 Tax-expressing tax-expressing JJ 451 456 human human JJ 457 469 T-lymphocyte T-lymphocyte NNP 470 474 line line NN 475 476 ( ( ( 476 486 Salahuddin Salahuddin NNP 487 489 et et FW 490 493 al. al. FW 493 494 , , , 495 499 1983 1983 CD 499 500 ) ) ) 500 501 , , , 502 506 that that WDT 507 515 interact interact VBP 516 520 with with IN 521 524 the the DT 525 532 TRE-DNA TRE-DNA NNP 532 533 , , , 534 538 none none NN 539 541 of of IN 542 547 which which WDT 548 551 are be VBP 552 561 identical identical JJ 562 566 with with IN 567 570 the the DT 571 582 Tax-protein Tax-protein NNP 582 583 . . . 584 587 The the DT 588 596 proteins protein NNS 597 607 identified identify VBN 608 612 have have VBP 613 622 molecular molecular JJ 623 630 weights weight NNS 631 633 of of IN 634 639 about about RB 640 642 32 32 CD 642 643 , , , 644 646 36 36 CD 647 649 to to TO 650 652 42 42 CD 652 653 , , , 654 656 50 50 CD 657 660 and and CC 661 664 110 110 CD 665 667 kD kd NN 667 668 . . . 669 673 Four four CD 674 683 different different JJ 684 691 methods method NNS 692 696 were be VBD 697 701 used use VBN 702 704 to to TO 705 713 identify identify VB 714 717 the the DT 718 726 proteins protein NNS 726 727 . . . 728 733 First first RB 733 734 , , , 735 739 from from IN 740 749 different different JJ 750 754 cell cell NN 755 760 lines line NNS 761 766 three three CD 767 769 or or CC 770 773 all all DT 774 778 four four CD 779 781 of of IN 782 785 the the DT 786 793 nuclear nuclear JJ 794 802 proteins protein NNS 803 807 were be VBD 808 820 specifically specifically RB 821 833 cross-linked cross-linke VBN 834 836 by by IN 837 839 UV UV NNP 840 851 irradiation irradiation NN 852 854 to to TO 855 858 the the DT 859 872 radioactively radioactively RB 873 880 labeled label VBN 881 888 TRE-DNA tre-dna JJ 889 897 fragment fragment NN 897 898 . . . 899 905 Second second RB 905 906 , , , 907 914 TRE-DNA TRE-DNA NNP 915 922 binding binding NN 923 931 proteins protein NNS 932 942 sedimented sedimente VBN 943 950 through through IN 951 952 a a DT 953 961 glycerol glycerol NN 962 969 density density NN 970 978 gradient gradient NN 979 981 at at IN 982 987 rates rate NNS 988 1001 corresponding correspond VBG 1002 1004 to to TO 1005 1013 proteins protein NNS 1014 1016 of of IN 1017 1023 native native JJ 1024 1033 molecular molecular JJ 1034 1041 weights weight NNS 1042 1044 of of IN 1045 1047 35 35 CD 1048 1050 to to TO 1051 1053 50 50 CD 1054 1056 kD kd NN 1057 1060 and and CC 1061 1064 110 110 CD 1065 1067 kD kd NN 1067 1068 . . . 1069 1074 Third third RB 1074 1075 , , , 1076 1080 only only RB 1081 1084 the the DT 1085 1087 50 50 CD 1088 1090 kD kd NN 1091 1098 protein protein NN 1099 1102 was be VBD 1103 1111 retained retain VBN 1112 1114 on on IN 1115 1116 a a DT 1117 1129 biotinylated biotinylate VBN 1130 1146 DNA-streptavidin DNA-streptavidin NNP 1147 1153 matrix matrix NN 1154 1158 when when WRB 1159 1162 the the DT 1163 1166 DNA DNA NNP 1167 1175 fragment fragment NN 1176 1185 contained contain VBD 1186 1189 the the DT 1190 1197 TRE-DNA tre-dna NN 1197 1198 . . . 1199 1205 Fourth fourth JJ 1205 1206 , , , 1207 1216 extensive extensive JJ 1217 1229 purification purification NN 1230 1232 by by IN 1233 1240 several several JJ 1241 1247 cycles cycle NNS 1248 1250 of of IN 1251 1258 TRE-DNA TRE-DNA NNP 1259 1267 affinity affinity NN 1268 1282 chromatography chromatography NN 1283 1291 resulted result VBD 1292 1294 in in IN 1295 1298 the the DT 1299 1301 32 32 CD 1301 1302 , , , 1303 1305 36 36 CD 1306 1308 to to TO 1309 1311 42 42 CD 1312 1315 and and CC 1316 1319 110 110 CD 1320 1322 kD kd NN 1323 1331 proteins protein NNS 1332 1335 and and CC 1336 1338 to to TO 1339 1343 less less JJR 1344 1350 extent extent NN 1351 1354 the the DT 1355 1357 50 50 CD 1358 1360 kD kd NN 1361 1367 factor factor NN 1367 1368 . . . 1369 1372 Two two CD 1373 1381 abundant abundant JJ 1382 1390 proteins protein NNS 1391 1393 of of IN 1394 1396 75 75 CD 1397 1400 and and CC 1401 1403 80 80 CD 1404 1406 kD kd NN 1407 1411 were be VBD 1412 1420 competed compete VBN 1421 1424 out out RP 1425 1427 by by IN 1428 1439 poly[d(I-C) poly[d(i-c) NN 1439 1440 ] ] ) 1441 1443 in in IN 1444 1447 all all DT 1448 1457 reactions reaction NNS 1457 1458 . . . 1459 1462 The the DT 1463 1476 cAMP-response camp-response JJ 1477 1484 element element NN 1485 1488 CRE CRE NNP 1488 1489 , , , 1490 1498 TGACGTCA TGACGTCA NNP 1498 1499 , , , 1500 1507 present present JJ 1508 1510 in in IN 1511 1514 the the DT 1515 1517 21 21 CD 1518 1527 base-pair base-pair NN 1528 1536 sequence sequence NN 1536 1537 , , , 1538 1545 appears appear VBZ 1546 1548 to to TO 1549 1551 be be VB 1552 1561 essential essential JJ 1562 1565 for for IN 1566 1574 specific specific JJ 1575 1590 protein-TRE-DNA protein-tre-dna JJ 1591 1603 interactions interaction NNS 1604 1611 because because IN 1612 1620 mutation mutation NN 1621 1623 of of IN 1624 1627 the the DT 1628 1631 two two CD 1632 1633 G G NNP 1633 1635 ’s 's POS 1636 1644 destroys destroy NNS 1645 1649 this this DT 1650 1657 complex complex NN 1657 1658 . . . 1659 1663 This this DT 1664 1670 result result NN 1671 1679 suggests suggest VBZ 1680 1684 that that IN 1685 1688 the the DT 1689 1693 cAMP camp NN 1694 1702 response response NN 1703 1710 element element NN 1711 1718 binding binding NN 1719 1726 protein protein NN 1726 1727 , , , 1728 1732 CREB CREB NNP 1732 1733 , , , 1734 1736 is be VBZ 1737 1745 involved involve VBN 1746 1748 in in IN 1749 1752 the the DT 1753 1768 protein-TRE-DNA protein-tre-dna JJ 1769 1776 complex complex NN 1777 1780 and and CC 1781 1783 in in IN 1784 1793 mediating mediate VBG 1794 1797 the the DT 1798 1801 Tax Tax NNP 1802 1810 response response NN 1810 1811 . . .