0 10 Functional functional JJ 11 18 Myc-Max Myc-Max NNP 19 30 heterodimer heterodimer NN 31 33 is be VBZ 34 42 required require VBN 43 46 for for IN 47 65 activation-induced activation-induced JJ 66 75 apoptosis apoptosis NN 76 78 in in IN 79 80 T t NN 81 85 cell cell NN 86 96 hybridomas hybridoma NNS 96 97 . . . 99 100 T t NN 101 105 cell cell NN 106 116 hybridomas hybridoma NNS 117 124 respond respond VBP 125 127 to to TO 128 138 activation activation NN 139 146 signals signal NNS 147 149 by by IN 150 160 undergoing undergo VBG 161 170 apoptotic apoptotic JJ 171 175 cell cell NN 176 181 death death NN 181 182 , , , 183 186 and and CC 187 191 this this DT 192 194 is be VBZ 195 201 likely likely JJ 202 204 to to TO 205 214 represent represent VB 215 225 comparable comparable JJ 226 232 events event NNS 233 240 related relate VBN 241 243 to to TO 244 253 tolerance tolerance NN 254 263 induction induction NN 264 266 in in IN 267 275 immature immature JJ 276 279 and and CC 280 286 mature mature JJ 287 288 T t NN 289 294 cells cell NNS 295 297 in in FW 298 302 vivo vivo FW 302 303 . . . 304 312 Previous previous JJ 313 320 studies study NNS 321 326 using use VBG 327 336 antisense antisense JJ 337 353 oligonucleotides oligonucleotide NNS 354 364 implicated implicate VBD 365 368 the the DT 369 374 c-Myc c-myc NN 375 382 protein protein NN 383 385 in in IN 386 389 the the DT 390 400 phenomenon phenomenon NN 401 403 of of IN 404 422 activation-induced activation-induced JJ 423 432 apoptosis apoptosis NN 432 433 . . . 434 438 This this DT 439 443 role role NN 444 447 for for IN 448 453 c-Myc c-myc NN 454 456 in in IN 457 466 apoptosis apoptosis NN 467 469 is be VBZ 470 473 now now RB 474 483 confirmed confirm VBN 484 486 in in IN 487 494 studies study NNS 495 500 using use VBG 501 502 a a DT 503 511 dominant dominant JJ 512 520 negative negative JJ 521 525 form form NN 526 528 of of IN 529 532 its its PRP$ 533 546 heterodimeric heterodimeric JJ 547 554 binding binding NN 555 562 partner partner NN 562 563 , , , 564 567 Max Max NNP 567 568 , , , 569 574 which which WDT 575 577 we we PRP 578 582 show show VBP 583 587 here here RB 588 596 inhibits inhibit VBZ 597 615 activation-induced activation-induced JJ 616 625 apoptosis apoptosis NN 625 626 . . . 627 634 Further further RB 634 635 , , , 636 648 coexpression coexpression NN 649 651 of of IN 652 653 a a DT 654 666 reciprocally reciprocally RB 667 673 mutant mutant JJ 674 677 Myc Myc NNP 678 685 protein protein NN 686 693 capable capable JJ 694 696 of of IN 697 704 forming form VBG 705 715 functional functional JJ 716 728 heterodimers heterodimer NNS 729 733 with with IN 734 737 the the DT 738 744 mutant mutant JJ 745 748 Max Max NNP 749 752 can can MD 753 763 compensate compensate VB 764 767 for for IN 768 771 the the DT 772 780 dominant dominant JJ 781 789 negative negative JJ 790 798 activity activity NN 799 802 and and CC 803 810 restore restore VB 811 829 activation-induced activation-induced JJ 830 839 apoptosis apoptosis NN 839 840 . . . 841 846 These these DT 847 854 results result NNS 855 860 imply imply VBP 861 865 that that IN 866 869 Myc Myc NNP 870 878 promotes promote VBZ 879 897 activation-induced activation-induced JJ 898 907 apoptosis apoptosis NN 908 910 by by IN 911 921 obligatory obligatory JJ 922 940 heterodimerization heterodimerization NN 941 945 with with IN 946 949 Max Max NNP 949 950 , , , 951 954 and and CC 955 964 therefore therefore RB 964 965 , , , 966 968 by by IN 969 979 regulating regulate VBG 980 984 gene gene NN 985 998 transcription transcription NN 998 999 . . .