0 11 Alternative alternative JJ 12 27 polyadenylation polyadenylation NN 28 34 events event NNS 35 45 contribute contribute VBP 46 48 to to TO 49 52 the the DT 53 62 induction induction NN 63 65 of of IN 66 72 NF-ATc NF-ATc NNP 73 75 in in IN 76 84 effector effector NN 85 86 T t NN 87 92 cells cell NNS 92 93 . . . 95 98 The the DT 99 112 transcription transcription NN 113 119 factor factor NN 120 126 NF-ATc NF-ATc NNP 127 129 is be VBZ 130 141 synthesized synthesize VBN 142 144 in in IN 145 150 three three CD 151 160 prominent prominent JJ 161 169 isoforms isoform NNS 169 170 . . . 171 176 These these DT 177 183 differ differ VBP 184 186 in in IN 187 190 the the DT 191 197 length length NN 198 200 of of IN 201 206 their their PRP$ 207 208 C C NNP 209 217 terminal terminal JJ 218 226 peptides peptide NNS 227 230 and and CC 231 235 mode mode NN 236 238 of of IN 239 248 synthesis synthesis NN 248 249 . . . 250 253 Due due JJ 254 256 to to TO 257 258 a a DT 259 265 switch switch NN 266 270 from from IN 271 274 the the DT 275 278 use use NN 279 281 of of IN 282 283 a a DT 284 285 3 3 CD 285 286 ’ ' SYM 287 292 polyA polya NN 293 297 site site NN 298 300 to to TO 301 302 a a DT 303 307 more more RBR 308 316 proximal proximal JJ 317 322 polyA polya NN 323 327 site site NN 327 328 , , , 329 335 NF-ATc NF-ATc NNP 336 346 expression expression NN 347 355 switches switch VBZ 356 360 from from IN 361 364 the the DT 365 374 synthesis synthesis NN 375 377 of of IN 378 381 the the DT 382 385 two two CD 386 392 longer long JJR 393 401 isoforms isoform NNS 402 404 in in IN 405 410 naive naive JJ 411 412 T t NN 413 418 cells cell NNS 419 421 to to TO 422 426 that that DT 427 429 of of IN 430 435 short short JJ 436 443 isoform isoform NN 444 445 A a NN 446 448 in in IN 449 450 T t NN 451 459 effector effector NN 460 465 cells cell NNS 465 466 . . . 467 470 The the DT 471 479 relative relative JJ 480 483 low low JJ 484 491 binding binding NN 492 500 affinity affinity NN 501 503 of of IN 504 512 cleavage cleavage NN 513 524 stimulation stimulation NN 525 531 factor factor NN 532 539 CstF-64 cstf-64 NN 540 542 to to TO 543 546 the the DT 547 555 proximal proximal JJ 556 561 polyA polya NN 562 566 site site NN 567 572 seems seem VBZ 573 575 to to TO 576 586 contribute contribute VB 587 589 to to TO 590 593 its its PRP$ 594 601 neglect neglect NN 602 604 in in IN 605 610 naive naive JJ 611 612 T t NN 613 618 cells cell NNS 618 619 . . . 620 625 These these DT 626 637 alternative alternative JJ 638 653 polyadenylation polyadenylation NN 654 660 events event NNS 661 667 ensure ensure VBP 668 671 the the DT 672 677 rapid rapid JJ 678 690 accumulation accumulation NN 691 693 of of IN 694 698 high high JJ 699 713 concentrations concentration NNS 714 716 of of IN 717 723 NF-ATc NF-ATc NNP 724 733 necessary necessary JJ 734 736 to to TO 737 743 exceed exceed VB 744 752 critical critical JJ 753 762 threshold threshold NN 763 769 levels level NNS 770 772 of of IN 773 779 NF-ATc NF-ATc NNP 780 783 for for IN 784 788 gene gene NN 789 798 induction induction NN 799 801 in in IN 802 810 effector effector NN 811 812 T t NN 813 818 cells cell NNS 818 819 . . .