0 1 A a DT 2 7 novel novel JJ 8 19 Ets-related ets-related JJ 20 33 transcription transcription NN 34 40 factor factor NN 40 41 , , , 42 47 Elf-1 Elf-1 NNP 47 48 , , , 49 54 binds bind VBZ 55 57 to to TO 58 63 human human JJ 64 80 immunodeficiency immunodeficiency NN 81 86 virus virus NN 87 91 type type NN 92 93 2 2 CD 94 104 regulatory regulatory JJ 105 113 elements element NNS 114 118 that that WDT 119 122 are be VBP 123 131 required require VBN 132 135 for for IN 136 145 inducible inducible JJ 146 151 trans trans JJ 152 162 activation activation NN 163 165 in in IN 166 167 T t NN 168 173 cells cell NNS 173 174 . . . 176 181 Human human JJ 182 198 immunodeficiency immunodeficiency NN 199 204 virus virus NN 205 209 type type NN 210 211 1 1 CD 212 213 ( ( ( 213 218 HIV-1 HIV-1 NNP 218 219 ) ) ) 220 223 and and CC 224 229 HIV-2 HIV-2 NNP 230 233 are be VBP 234 246 structurally structurally RB 247 254 related relate VBN 255 267 retroviruses retrovirus NNS 268 273 which which WDT 274 278 both both DT 279 284 cause cause VBP 285 289 AIDS AIDS NNP 290 292 in in IN 293 299 humans human NNS 299 300 . . . 301 309 Although although IN 310 314 both both DT 315 322 viruses virus NNS 323 332 establish establish VBP 333 340 latency latency NN 341 343 in in IN 344 353 quiescent quiescent JJ 354 376 human-peripheral-blood human-peripheral-blood JJ 377 378 T t NN 379 384 cells cell NNS 384 385 , , , 386 389 the the DT 390 402 asymptomatic asymptomatic JJ 403 408 phase phase NN 409 411 of of IN 412 417 HIV-2 hiv-2 NN 418 427 infection infection NN 428 431 may may MD 432 434 be be VB 435 439 more more RBR 440 449 prolonged prolonged JJ 450 454 than than IN 455 459 that that DT 460 462 of of IN 463 468 HIV-1 HIV-1 NNP 468 469 . . . 470 473 The the DT 474 480 latent latent JJ 481 487 phases phase NNS 488 490 of of IN 491 495 both both CC 496 501 HIV-1 HIV-1 NNP 502 505 and and CC 506 511 HIV-2 hiv-2 NN 512 521 infection infection NN 522 526 have have VBP 527 531 been be VBN 532 537 shown show VBN 538 540 to to TO 541 543 be be VB 544 553 disrupted disrupt VBN 554 556 by by IN 557 563 T-cell t-cell NN 564 574 activation activation NN 574 575 , , , 576 577 a a DT 578 585 process process NN 586 590 that that WDT 591 599 requires require VBZ 600 604 host host NN 605 609 cell cell NN 610 623 transcription transcription NN 624 631 factors factor NNS 631 632 . . . 633 635 In in IN 636 639 the the DT 640 644 case case NN 645 647 of of IN 648 653 HIV-1 HIV-1 NNP 653 654 , , , 655 658 the the DT 659 672 transcription transcription NN 673 679 factor factor NN 680 688 NF-kappa NF-kappa NNP 689 690 B B NNP 691 693 is be VBZ 694 704 sufficient sufficient JJ 705 708 for for IN 709 718 inducible inducible JJ 719 734 transcriptional transcriptional JJ 735 745 activation activation NN 745 746 . . . 747 749 In in IN 750 758 contrast contrast NN 758 759 , , , 760 767 factors factor NNS 768 770 in in IN 771 779 addition addition NN 780 782 to to TO 783 791 NF-kappa NF-kappa NNP 792 793 B B NNP 794 797 are be VBP 798 806 required require VBN 807 809 to to TO 810 818 activate activate VB 819 824 HIV-2 hiv-2 NN 825 838 transcription transcription NN 839 841 in in IN 842 850 infected infected JJ 851 852 T t NN 853 858 cells cell NNS 858 859 . . . 860 862 In in IN 863 867 this this DT 868 874 report report NN 874 875 , , , 876 878 we we PRP 879 890 demonstrate demonstrate VBP 891 895 that that IN 896 897 a a DT 898 903 novel novel JJ 904 915 Ets-related ets-related JJ 916 929 transcription transcription NN 930 936 factor factor NN 936 937 , , , 938 943 Elf-1 Elf-1 NNP 943 944 , , , 945 950 binds bind VBZ 951 963 specifically specifically RB 964 966 to to TO 967 970 two two CD 971 982 purine-rich purine-rich JJ 983 989 motifs motif NNS 990 992 in in IN 993 996 the the DT 997 1002 HIV-2 hiv-2 NN 1003 1011 enhancer enhancer NN 1011 1012 . . . 1013 1024 Mutagenesis Mutagenesis NNP 1025 1036 experiments experiment NNS 1037 1049 demonstrated demonstrate VBD 1050 1054 that that IN 1055 1060 these these DT 1061 1066 Elf-1 elf-1 NN 1067 1074 binding binding NN 1075 1080 sites site NNS 1081 1084 are be VBP 1085 1093 required require VBN 1094 1097 for for IN 1098 1107 induction induction NN 1108 1110 of of IN 1111 1116 HIV-2 hiv-2 NN 1117 1130 transcription transcription NN 1131 1140 following follow VBG 1141 1165 T-cell-receptor-mediated t-cell-receptor-mediated JJ 1166 1172 T-cell T-cell NNP 1173 1183 activation activation NN 1183 1184 . . . 1185 1193 Moreover moreover RB 1193 1194 , , , 1195 1200 Elf-1 Elf-1 NNP 1201 1203 is be VBZ 1204 1207 the the DT 1208 1212 only only JJ 1213 1219 factor factor NN 1220 1227 present present JJ 1228 1230 in in IN 1231 1240 activated activate VBN 1241 1247 T-cell t-cell NN 1248 1255 nuclear nuclear JJ 1256 1264 extracts extract NNS 1265 1269 that that WDT 1270 1275 binds bind VBZ 1276 1278 to to TO 1279 1284 these these DT 1285 1290 sites site NNS 1291 1293 in in IN 1294 1309 electrophoretic electrophoretic JJ 1310 1318 mobility mobility NN 1319 1324 shift shift NN 1325 1331 assays assay NNS 1331 1332 . . . 1333 1337 Thus thus RB 1337 1338 , , , 1339 1344 Elf-1 Elf-1 NNP 1345 1347 is be VBZ 1348 1349 a a DT 1350 1355 novel novel JJ 1356 1369 transcription transcription NN 1370 1376 factor factor NN 1377 1381 that that WDT 1382 1389 appears appear VBZ 1390 1392 to to TO 1393 1395 be be VB 1396 1404 required require VBN 1405 1408 for for IN 1409 1412 the the DT 1413 1437 T-cell-receptor-mediated t-cell-receptor-mediated JJ 1438 1443 trans trans JJ 1444 1454 activation activation NN 1455 1457 of of IN 1458 1463 HIV-2 hiv-2 NN 1464 1468 gene gene NN 1469 1479 expression expression NN 1479 1480 . . . 1481 1486 These these DT 1487 1494 results result NNS 1495 1498 may may MD 1499 1506 explain explain VB 1507 1518 differences difference NNS 1519 1521 in in IN 1522 1525 the the DT 1526 1534 clinical clinical JJ 1535 1542 spectra spectrum NNS 1543 1545 of of IN 1546 1554 diseases disease NNS 1555 1561 caused cause VBN 1562 1564 by by IN 1565 1570 HIV-1 HIV-1 NNP 1571 1574 and and CC 1575 1580 HIV-2 HIV-2 NNP 1581 1584 and and CC 1585 1588 may may MD 1589 1593 also also RB 1594 1598 have have VB 1599 1611 implications implication NNS 1612 1615 for for IN 1616 1619 the the DT 1620 1626 design design NN 1627 1629 of of IN 1630 1641 therapeutic therapeutic JJ 1642 1652 approaches approach NNS 1653 1655 to to TO 1656 1661 HIV-2 hiv-2 NN 1662 1671 infection infection NN 1671 1672 . . .