0 7 Octamer Octamer NNP 8 21 transcription transcription NN 22 29 factors factor NNS 30 33 and and CC 34 37 the the DT 38 42 cell cell NN 43 59 type-specificity type-specificity NN 60 62 of of IN 63 77 immunoglobulin immunoglobulin NN 78 82 gene gene NN 83 93 expression expression NN 93 94 . . . 96 106 Antibodies antibody NNS 107 110 are be VBP 111 119 produced produce VBN 120 131 exclusively exclusively RB 132 134 in in IN 135 136 B B NNP 137 148 lymphocytes lymphocyte NNS 148 149 . . . 150 153 The the DT 154 164 expression expression NN 165 167 of of IN 168 171 the the DT 172 189 antibody-encoding antibody-encoding JJ 190 195 genes gene NNS 195 196 , , , 197 200 the the DT 201 215 immunoglobulin immunoglobulin NN 216 217 ( ( ( 217 219 Ig Ig NNP 219 220 ) ) ) 221 226 genes gene NNS 226 227 , , , 228 230 is be VBZ 231 235 also also RB 236 246 restricted restrict VBN 247 249 to to TO 250 251 B B NNP 252 257 cells cell NNS 257 258 . . . 259 262 The the DT 263 270 octamer octamer NN 271 279 sequence sequence NN 280 288 ATGCAAAT atgcaaat NN 289 291 is be VBZ 292 299 present present JJ 300 302 in in IN 303 306 the the DT 307 315 promoter promoter NN 316 319 and and CC 320 323 the the DT 324 332 enhancer enhancer NN 333 335 of of IN 336 338 Ig ig NN 339 344 genes gene NNS 344 345 , , , 346 349 and and CC 350 355 plays play VBZ 356 358 an an DT 359 368 important important JJ 369 373 role role NN 374 376 in in IN 377 380 its its PRP$ 381 396 tissue-specific tissue-specific JJ 397 407 expression expression NN 407 408 . . . 409 413 This this DT 414 422 sequence sequence NN 423 428 motif motif NN 429 431 is be VBZ 432 433 a a DT 434 441 binding bind VBG 442 446 site site NN 447 450 for for IN 451 458 nuclear nuclear JJ 459 467 proteins protein NNS 467 468 , , , 469 472 the the DT 473 482 so-called so-called JJ 483 490 octamer octamer NN 491 504 transcription transcription NN 505 512 factors factor NNS 513 514 ( ( ( 514 517 Oct Oct NNP 518 520 or or CC 521 524 OTF OTF NNP 525 532 factors factor NNS 532 533 ) ) ) 533 534 . . . 535 538 The the DT 539 544 Oct-1 oct-1 NN 545 552 protein protein NN 553 555 is be VBZ 556 563 present present JJ 564 566 in in IN 567 570 all all DT 571 575 cell cell NN 576 581 types type NNS 582 590 analyzed analyze VBN 591 593 so so RB 594 597 far far RB 597 598 , , , 599 606 whereas whereas IN 607 613 Oct-2A Oct-2A NNP 614 617 and and CC 618 624 Oct-2B Oct-2B NNP 625 628 are be VBP 629 634 found find VBN 635 641 mainly mainly RB 642 644 in in IN 645 646 B B NNP 647 658 lymphocytes lymphocyte NNS 658 659 . . . 660 663 All all DT 664 669 three three CD 670 678 proteins protein NNS 679 683 show show VBP 684 687 the the DT 688 692 same same JJ 693 701 sequence sequence NN 702 713 specificity specificity NN 714 717 and and CC 718 725 binding binding NN 726 734 affinity affinity NN 734 735 . . . 736 738 It it PRP 739 746 appears appear VBZ 747 751 that that IN 752 755 the the DT 756 757 B B NNP 758 771 cell-specific cell-specific JJ 772 782 expression expression NN 783 785 of of IN 786 788 Ig ig NN 789 794 genes gene NNS 795 797 is be VBZ 798 806 mediated mediate VBN 807 809 at at IN 810 815 least least JJS 816 818 in in IN 819 823 part part NN 824 826 by by IN 827 831 cell cell NN 832 845 type-specific type-specific JJ 846 849 Oct Oct NNP 850 857 factors factor NNS 857 858 , , , 859 862 and and CC 863 867 that that IN 868 873 there there EX 874 877 are be VBP 878 882 both both DT 883 895 quantitative quantitative JJ 896 899 and and CC 900 911 qualitative qualitative JJ 912 923 differences difference NNS 924 931 between between IN 932 937 Oct-1 oct-1 NN 938 941 and and CC 942 947 Oct-2 oct-2 NN 948 955 factors factor NNS 955 956 . . . 957 965 Recently recently RB 965 966 , , , 967 968 a a DT 969 975 number number NN 976 978 of of IN 979 984 other other JJ 985 992 octamer octamer NN 993 999 factor factor NN 1000 1008 variants variant NNS 1009 1013 were be VBD 1014 1024 identified identify VBN 1024 1025 . . . 1026 1030 Many many JJ 1031 1033 of of IN 1034 1039 these these DT 1040 1043 may may MD 1044 1046 be be VB 1047 1054 created create VBN 1055 1057 by by IN 1058 1069 alternative alternative JJ 1070 1078 splicing splicing NN 1079 1081 of of IN 1082 1083 a a DT 1084 1091 primary primary JJ 1092 1102 transcript transcript NN 1103 1105 of of IN 1106 1109 one one CD 1110 1113 Oct Oct NNP 1114 1120 factor factor NN 1121 1125 gene gene NN 1126 1129 and and CC 1130 1133 may may MD 1134 1139 serve serve VB 1140 1141 a a DT 1142 1150 specific specific JJ 1151 1159 function function NN 1160 1162 in in IN 1163 1166 the the DT 1167 1171 fine fine JJ 1172 1178 tuning tuning NN 1179 1181 of of IN 1182 1186 gene gene NN 1187 1197 expression expression NN 1197 1198 . . .