0 7 Central central JJ 8 15 nervous nervous JJ 16 30 system-derived system-derived JJ 31 36 cells cell NNS 37 44 express express VBP 45 46 a a DT 47 52 kappa kappa NN 53 62 B-binding b-binding JJ 63 71 activity activity NN 72 76 that that WDT 77 85 enhances enhance VBZ 86 91 human human JJ 92 108 immunodeficiency immunodeficiency NN 109 114 virus virus NN 115 119 type type NN 120 121 1 1 CD 122 135 transcription transcription NN 136 138 in in FW 139 144 vitro vitro FW 145 148 and and CC 149 160 facilitates facilitate VBZ 161 176 TAR-independent tar-independent JJ 177 192 transactivation transactivation NN 193 195 by by IN 196 199 Tat Tat NNP 199 200 . . . 202 205 The the DT 206 209 Tat Tat NNP 210 217 protein protein NN 218 220 of of IN 221 226 human human JJ 227 243 immunodeficiency immunodeficiency NN 244 249 virus virus NN 250 254 type type NN 255 256 1 1 CD 257 258 ( ( ( 258 263 HIV-1 HIV-1 NNP 263 264 ) ) ) 265 267 is be VBZ 268 269 a a DT 270 276 potent potent JJ 277 286 activator activator NN 287 289 of of IN 290 294 long long JJ 295 303 terminal terminal JJ 304 319 repeat-directed repeat-directed JJ 320 333 transcription transcription NN 333 334 . . . 335 340 While while IN 341 343 in in IN 344 348 most most JJS 349 353 cell cell NN 354 359 types type NNS 359 360 , , , 361 371 activation activation NN 372 380 requires require VBZ 381 392 interaction interaction NN 393 395 of of IN 396 399 Tat Tat NNP 400 404 with with IN 405 408 the the DT 409 416 unusual unusual JJ 417 430 transcription transcription NN 431 438 element element NN 439 442 TAR tar NN 442 443 , , , 444 454 astrocytic astrocytic JJ 455 460 glial glial JJ 461 466 cells cell NNS 467 474 support support VBP 475 490 TAR-independent tar-independent JJ 491 506 transactivation transactivation NN 507 509 of of IN 510 515 HIV-1 HIV-1 NNP 516 529 transcription transcription NN 530 532 by by IN 533 536 Tat Tat NNP 536 537 . . . 538 542 This this DT 543 554 alternative alternative JJ 555 562 pathway pathway NN 563 565 of of IN 566 569 Tat Tat NNP 570 580 activation activation NN 581 583 is be VBZ 584 592 mediated mediate VBN 593 595 by by IN 596 599 the the DT 600 605 viral viral JJ 606 614 enhancer enhancer NN 614 615 , , , 616 617 a a DT 618 623 kappa kappa NN 624 625 B B NNP 626 632 domain domain NN 633 640 capable capable JJ 641 643 of of IN 644 651 binding bind VBG 652 655 the the DT 656 668 prototypical prototypical JJ 669 673 form form NN 674 676 of of IN 677 680 the the DT 681 694 transcription transcription NN 695 701 factor factor NN 702 709 nuclear nuclear JJ 710 716 factor factor NN 717 722 kappa kappa NN 723 724 B B NNP 725 726 ( ( ( 726 734 NF-kappa NF-kappa NNP 735 736 B B NNP 736 737 ) ) ) 738 745 present present JJ 746 748 in in IN 749 753 many many JJ 754 758 cell cell NN 759 764 types type NNS 764 765 , , , 766 775 including include VBG 776 777 T t NN 778 789 lymphocytes lymphocyte NNS 789 790 . . . 791 794 Tat Tat NNP 795 810 transactivation transactivation NN 811 819 mediated mediate VBN 820 822 by by IN 823 826 the the DT 827 832 kappa kappa NN 833 834 B B NNP 835 841 domain domain NN 842 844 is be VBZ 845 855 sufficient sufficient JJ 856 858 to to TO 859 864 allow allow VB 865 876 replication replication NN 877 879 of of IN 880 891 TAR-deleted tar-deleted JJ 892 898 mutant mutant JJ 899 904 HIV-1 HIV-1 NNP 905 907 in in IN 908 918 astrocytes astrocyte NNS 918 919 . . . 920 923 The the DT 924 931 present present JJ 932 937 study study NN 938 950 demonstrates demonstrate VBZ 951 954 the the DT 955 964 existence existence NN 965 967 of of IN 968 973 kappa kappa NN 974 984 B-specific b-specific JJ 985 992 binding binding NN 993 1000 factors factor NNS 1001 1008 present present JJ 1009 1011 in in IN 1012 1017 human human JJ 1018 1023 glial glial JJ 1024 1034 astrocytes astrocyte NNS 1035 1039 that that WDT 1040 1046 differ differ VBP 1047 1051 from from IN 1052 1064 prototypical prototypical JJ 1065 1073 NF-kappa NF-kappa NNP 1074 1076 B. B. NNP 1077 1080 The the DT 1081 1086 novel novel JJ 1087 1104 astrocyte-derived astrocyte-derived JJ 1105 1110 kappa kappa NN 1111 1120 B-binding b-binding JJ 1121 1129 activity activity NN 1130 1132 is be VBZ 1133 1141 retained retain VBN 1142 1144 on on IN 1145 1147 an an DT 1148 1153 HIV-1 HIV-1 NNP 1154 1157 Tat Tat NNP 1158 1166 affinity affinity NN 1167 1173 column column NN 1173 1174 , , , 1175 1180 while while IN 1181 1193 prototypical prototypical JJ 1194 1202 NF-kappa NF-kappa NNP 1203 1204 B B NNP 1205 1209 from from IN 1210 1216 Jurkat Jurkat NNP 1217 1218 T t NN 1219 1224 cells cell NNS 1225 1227 is be VBZ 1228 1231 not not RB 1231 1232 . . . 1233 1235 In in FW 1236 1241 vitro vitro FW 1242 1255 transcription transcription NN 1256 1263 studies study NNS 1264 1275 demonstrate demonstrate VBP 1276 1280 that that IN 1281 1298 astrocyte-derived astrocyte-derived JJ 1299 1304 kappa kappa NN 1305 1314 B-binding b-binding JJ 1315 1322 factors factor NNS 1323 1331 activate activate VBP 1332 1345 transcription transcription NN 1346 1348 of of IN 1349 1352 the the DT 1353 1358 HIV-1 HIV-1 NNP 1359 1363 long long JJ 1364 1372 terminal terminal JJ 1373 1379 repeat repeat NN 1380 1383 and and CC 1384 1388 that that IN 1389 1393 this this DT 1394 1404 activation activation NN 1405 1407 is be VBZ 1408 1417 dependent dependent JJ 1418 1420 on on IN 1421 1424 the the DT 1425 1430 kappa kappa NN 1431 1432 B B NNP 1433 1439 domain domain NN 1439 1440 . . . 1441 1449 Moreover moreover RB 1449 1450 , , , 1451 1466 TAR-independent tar-independent JJ 1467 1482 transactivation transactivation NN 1483 1485 of of IN 1486 1491 HIV-1 HIV-1 NNP 1492 1505 transcription transcription NN 1506 1508 is be VBZ 1509 1519 reproduced reproduce VBN 1520 1522 in in FW 1523 1528 vitro vitro FW 1529 1531 in in IN 1532 1534 an an DT 1535 1544 astrocyte astrocyte NN 1545 1561 factor-dependent factor-dependent JJ 1562 1568 manner manner NN 1569 1574 which which WDT 1575 1585 correlates correlate VBZ 1586 1590 with with IN 1591 1596 kappa kappa NN 1597 1606 B-binding b-binding JJ 1607 1615 activity activity NN 1615 1616 . . . 1617 1620 The the DT 1621 1631 importance importance NN 1632 1634 of of IN 1635 1638 the the DT 1639 1646 central central JJ 1647 1654 nervous nervous JJ 1655 1670 system-enriched system-enriched JJ 1671 1676 kappa kappa NN 1677 1678 B B NNP 1679 1692 transcription transcription NN 1693 1699 factor factor NN 1700 1702 in in IN 1703 1706 the the DT 1707 1717 regulation regulation NN 1718 1720 of of IN 1721 1726 HIV-1 HIV-1 NNP 1727 1737 expression expression NN 1738 1740 is be VBZ 1741 1750 discussed discuss VBN 1750 1751 . . .