0 5 Human human JJ 6 22 immunodeficiency immunodeficiency NN 23 28 virus virus NN 29 35 type-1 type-1 NN 36 49 transcription transcription NN 49 50 : : : 51 55 role role NN 56 58 of of IN 59 62 the the DT 63 78 5’-untranslated 5'-untranslated JJ 79 85 leader leader NN 86 92 region region NN 93 94 ( ( ( 94 100 review review NN 100 101 ) ) ) 101 102 . . . 104 109 Human human JJ 110 126 immunodeficiency immunodeficiency NN 127 132 virus virus NN 133 139 type-1 type-1 NN 140 141 ( ( ( 141 146 HIV-1 HIV-1 NNP 146 147 ) ) ) 148 161 transcription transcription NN 162 164 is be VBZ 165 174 dependent dependent JJ 175 177 on on IN 178 181 the the DT 182 193 interaction interaction NN 194 196 of of IN 197 206 host-cell host-cell NN 207 220 transcription transcription NN 221 228 factors factor NNS 229 233 with with IN 234 248 cis-regulatory cis-regulatory JJ 249 252 DNA dna NN 253 261 elements element NNS 262 268 within within IN 269 272 the the DT 273 278 viral viral JJ 279 283 long long JJ 284 292 terminal terminal JJ 293 299 repeat repeat NN 300 301 ( ( ( 301 304 LTR LTR NNP 304 305 ) ) ) 305 306 . . . 307 311 Much much JJ 312 321 attention attention NN 322 325 has have VBZ 326 333 focused focus VBN 334 336 on on IN 337 340 the the DT 341 347 series series NN 348 350 of of IN 351 359 sequence sequence NN 360 368 elements element NNS 369 377 upstream upstream JJ 378 380 of of IN 381 384 the the DT 385 400 transcriptional transcriptional JJ 401 411 initiation initiation NN 412 416 site site NN 417 419 in in IN 420 423 the the DT 424 426 U3 u3 NN 427 433 region region NN 434 436 of of IN 437 440 the the DT 441 444 LTR ltr NN 445 454 including include VBG 455 458 the the DT 459 462 Sp1 Sp1 NNP 463 466 and and CC 467 476 NF-kappaB NF-kappaB NNP 477 484 binding binding NN 485 490 sites site NNS 490 491 . . . 492 498 Recent recent JJ 499 506 studies study NNS 506 507 , , , 508 515 however however RB 515 516 , , , 517 528 demonstrate demonstrate VBP 529 533 that that IN 534 537 the the DT 538 549 transcribed transcribe VBN 550 565 5’-untranslated 5'-untranslated JJ 566 572 leader leader NN 573 579 region region NN 580 581 ( ( ( 581 587 5’-UTR 5'-UTR NNP 587 588 ) ) ) 589 593 also also RB 594 602 contains contain VBZ 603 612 important important JJ 613 628 transcriptional transcriptional JJ 629 637 elements element NNS 637 638 . . . 639 644 These these DT 645 655 regulatory regulatory JJ 656 664 elements element NNS 665 673 situated situate VBN 674 684 downstream downstream RB 685 687 of of IN 688 701 transcription transcription NN 702 710 interact interact VBP 711 715 with with IN 716 728 constitutive constitutive JJ 729 732 and and CC 733 742 inducible inducible JJ 743 756 transcription transcription NN 757 764 factors factor NNS 764 765 , , , 766 773 mediate mediate VBP 774 786 transmission transmission NN 787 789 of of IN 790 798 cellular cellular JJ 799 809 activation activation NN 810 817 signals signal NNS 817 818 , , , 819 822 and and CC 823 826 are be VBP 827 836 important important JJ 837 840 for for IN 841 850 efficient efficient JJ 851 856 HIV-1 HIV-1 NNP 857 870 transcription transcription NN 871 874 and and CC 875 886 replication replication NN 886 887 . . . 888 891 The the DT 892 898 5’-UTR 5'-UTR NNP 899 907 contains contain VBZ 908 915 binding bind VBG 916 921 sites site NNS 922 925 for for IN 926 929 the the DT 930 943 transcription transcription NN 944 951 factors factor NNS 952 956 AP-1 ap-1 NN 956 957 , , , 958 967 NF-kappaB NF-kappaB NNP 967 968 , , , 969 974 NF-AT NF-AT NNP 974 975 , , , 976 979 IRF IRF NNP 979 980 , , , 981 984 and and CC 985 988 Sp1 Sp1 NNP 988 989 . . . 990 999 Mutations mutation NNS 1000 1002 in in IN 1003 1008 these these DT 1009 1016 binding bind VBG 1017 1022 sites site NNS 1023 1026 can can MD 1027 1036 interfere interfere VB 1037 1041 with with IN 1042 1045 the the DT 1046 1051 viral viral JJ 1052 1060 response response NN 1061 1063 to to TO 1064 1068 cell cell NN 1069 1079 activation activation NN 1080 1087 signals signal NNS 1087 1088 , , , 1089 1097 decrease decrease VB 1098 1101 LTR ltr NN 1102 1115 transcription transcription NN 1115 1116 , , , 1117 1120 and and CC 1121 1128 inhibit inhibit VB 1129 1134 viral viral JJ 1135 1146 replication replication NN 1146 1147 . . . 1148 1151 The the DT 1152 1158 5’-UTR 5'-UTR NNP 1159 1163 also also RB 1164 1173 interacts interact VBZ 1174 1178 with with IN 1179 1180 a a DT 1181 1189 specific specific JJ 1190 1200 nucleosome nucleosome NN 1201 1205 that that WDT 1206 1208 is be VBZ 1209 1216 rapidly rapidly RB 1217 1226 displaced displace VBN 1227 1233 during during IN 1234 1249 transcriptional transcriptional JJ 1250 1260 activation activation NN 1261 1263 of of IN 1264 1267 the the DT 1268 1274 latent latent JJ 1275 1283 provirus provirus NN 1283 1284 . . . 1285 1287 We we PRP 1288 1295 propose propose VBP 1296 1300 that that IN 1301 1304 the the DT 1305 1314 inducible inducible JJ 1315 1328 transcription transcription NN 1329 1335 factor factor NN 1336 1343 binding binding NN 1344 1349 sites site NNS 1350 1352 in in IN 1353 1356 the the DT 1357 1363 5’-UTR 5'-UTR NNP 1364 1372 comprise comprise VBP 1373 1374 a a DT 1375 1385 downstream downstream JJ 1386 1394 enhancer enhancer NN 1395 1401 domain domain NN 1402 1406 that that WDT 1407 1410 can can MD 1411 1419 function function VB 1420 1431 independent independent JJ 1432 1434 of of IN 1434 1435 , , , 1436 1438 or or CC 1439 1441 in in IN 1442 1449 concert concert NN 1450 1454 with with IN 1454 1455 , , , 1456 1459 the the DT 1460 1463 LTR LTR NNP 1464 1472 promoter promoter NN 1473 1475 to to TO 1476 1483 rapidly rapidly RB 1484 1492 increase increase VB 1493 1499 latent latent JJ 1500 1508 proviral proviral JJ 1509 1522 transcription transcription NN 1523 1525 in in IN 1526 1534 response response NN 1535 1537 to to TO 1538 1542 cell cell NN 1543 1553 activation activation NN 1554 1561 signals signal NNS 1561 1562 . . . 1563 1565 In in IN 1566 1570 this this DT 1571 1577 review review NN 1577 1578 , , , 1579 1581 we we PRP 1582 1590 describe describe VBP 1591 1594 the the DT 1595 1604 host-cell host-cell JJ 1605 1618 transcription transcription NN 1619 1626 factors factor NNS 1627 1631 that that WDT 1632 1640 interact interact VBP 1641 1645 with with IN 1646 1649 the the DT 1650 1656 5’-UTR 5'-UTR NNP 1657 1660 and and CC 1661 1668 discuss discuss VBP 1669 1674 their their PRP$ 1675 1679 role role NN 1680 1682 in in IN 1683 1686 the the DT 1687 1702 transcriptional transcriptional JJ 1703 1713 regulation regulation NN 1714 1716 of of IN 1717 1722 HIV-1 HIV-1 NNP 1723 1727 gene gene NN 1728 1738 expression expression NN 1738 1739 . . .