0 3 The the DT 4 15 DNA-binding dna-binding JJ 16 26 properties property NNS 27 29 of of IN 30 33 two two CD 34 38 heat heat NN 39 44 shock shock NN 45 52 factors factor NNS 52 53 , , , 54 58 HSF1 HSF1 NNP 59 62 and and CC 63 67 HSF3 HSF3 NNP 67 68 , , , 69 72 are be VBP 73 80 induced induce VBN 81 83 in in IN 84 87 the the DT 88 93 avian avian JJ 94 106 erythroblast erythroblast NN 107 111 cell cell NN 112 116 line line NN 117 120 HD6 hd6 NN 120 121 . . . 123 128 Avian avian JJ 129 134 cells cell NNS 135 142 express express VBP 143 148 three three CD 149 153 heat heat NN 154 159 shock shock NN 160 173 transcription transcription NN 174 180 factor factor NN 181 182 ( ( ( 182 185 HSF HSF NNP 185 186 ) ) ) 187 192 genes gene NNS 193 206 corresponding correspond VBG 207 209 to to TO 210 211 a a DT 212 217 novel novel JJ 218 224 factor factor NN 224 225 , , , 226 230 HSF3 HSF3 NNP 230 231 , , , 232 235 and and CC 236 244 homologs homolog NNS 245 247 of of IN 248 253 mouse mouse NN 254 257 and and CC 258 263 human human JJ 264 268 HSF1 hsf1 NN 269 272 and and CC 273 277 HSF2 hsf2 NN 277 278 . . . 279 287 Analysis Analysis NNP 288 290 of of IN 291 294 the the DT 295 306 biochemical biochemical JJ 307 310 and and CC 311 315 cell cell NN 316 326 biological biological JJ 327 337 properties property NNS 338 340 of of IN 341 346 these these DT 347 351 HSFs HSF NNP 352 359 reveals reveal VBZ 360 364 that that IN 365 369 HSF3 hsf3 NN 370 373 has have VBZ 374 384 properties property NNS 385 387 in in IN 388 394 common common JJ 395 399 with with IN 400 404 both both CC 405 409 HSF1 hsf1 NN 410 413 and and CC 414 418 HSF2 hsf2 NN 419 422 and and CC 423 426 yet yet RB 427 430 has have VBZ 431 439 features feature NNS 440 445 which which WDT 446 449 are be VBP 450 458 distinct distinct JJ 459 463 from from IN 464 468 both both DT 468 469 . . . 470 474 HSF3 HSF3 NNP 475 477 is be VBZ 478 492 constitutively constitutively RB 493 502 expressed express VBN 503 505 in in IN 506 509 the the DT 510 522 erythroblast erythroblast NN 523 527 cell cell NN 528 532 line line NN 533 536 HD6 HD6 NNP 536 537 , , , 538 541 the the DT 542 553 lymphoblast lymphoblast NN 554 558 cell cell NN 559 563 line line NN 564 567 MSB MSB NNP 567 568 , , , 569 572 and and CC 573 579 embryo embryo NN 580 591 fibroblasts fibroblast NNS 591 592 , , , 593 596 and and CC 597 600 yet yet RB 601 604 its its PRP$ 605 616 DNA-binding dna-binding JJ 617 625 activity activity NN 626 628 is be VBZ 629 636 induced induce VBN 637 641 only only RB 642 646 upon upon IN 647 655 exposure exposure NN 656 658 of of IN 659 662 HD6 HD6 NNP 663 668 cells cell NNS 669 671 to to TO 672 676 heat heat NN 677 682 shock shock NN 682 683 . . . 684 695 Acquisition Acquisition NNP 696 698 of of IN 699 703 HSF3 HSF3 NNP 704 715 DNA-binding dna-binding JJ 716 724 activity activity NN 725 727 in in IN 728 731 HD6 HD6 NNP 732 737 cells cell NNS 738 740 is be VBZ 741 752 accompanied accompany VBN 753 755 by by IN 756 771 oligomerization oligomerization NN 772 776 from from IN 777 778 a a DT 779 794 non-DNA-binding non-dna-binding JJ 795 800 dimer dimer NN 801 803 to to TO 804 805 a a DT 806 817 DNA-binding dna-binding JJ 818 824 trimer trimer NN 824 825 , , , 826 833 whereas whereas IN 834 837 the the DT 838 844 effect effect NN 845 847 of of IN 848 852 heat heat NN 853 858 shock shock NN 859 861 on on IN 862 866 HSF1 HSF1 NNP 867 869 is be VBZ 870 885 oligomerization oligomerization NN 886 888 of of IN 889 891 an an DT 892 897 inert inert JJ 898 905 monomer monomer NN 906 908 to to TO 909 910 a a DT 911 922 DNA-binding dna-binding JJ 923 929 trimer trimer NN 929 930 . . . 931 940 Induction Induction NNP 941 943 of of IN 944 948 HSF3 HSF3 NNP 949 960 DNA-binding dna-binding JJ 961 969 activity activity NN 970 972 is be VBZ 973 980 delayed delay VBN 981 989 compared compare VBN 990 994 with with IN 995 999 that that DT 1000 1002 of of IN 1003 1007 HSF1 HSF1 NNP 1007 1008 . . . 1009 1011 As as IN 1012 1018 occurs occur VBZ 1019 1022 for for IN 1023 1027 HSF1 HSF1 NNP 1027 1028 , , , 1029 1033 heat heat NN 1034 1039 shock shock NN 1040 1045 leads lead VBZ 1046 1048 to to TO 1049 1052 the the DT 1053 1066 translocation translocation NN 1067 1069 of of IN 1070 1074 HSF3 hsf3 NN 1075 1077 to to TO 1078 1081 the the DT 1082 1089 nucleus nucleus NN 1089 1090 . . . 1091 1094 HSF HSF NNP 1095 1103 exhibits exhibit VBZ 1104 1107 the the DT 1108 1118 properties property NNS 1119 1121 of of IN 1122 1123 a a DT 1124 1139 transcriptional transcriptional JJ 1140 1149 activator activator NN 1149 1150 , , , 1151 1153 as as IN 1154 1160 judged judge VBN 1161 1165 from from IN 1166 1169 the the DT 1170 1181 stimulatory stimulatory JJ 1182 1190 activity activity NN 1191 1193 of of IN 1194 1205 transiently transiently RB 1206 1219 overexpressed overexpresse VBN 1220 1224 HSF3 hsf3 NN 1225 1233 measured measure VBN 1234 1236 by by IN 1237 1242 using use VBG 1243 1244 a a DT 1245 1249 heat heat NN 1250 1255 shock shock NN 1256 1274 element-containing element-containing JJ 1275 1283 reporter reporter NN 1284 1293 construct construct NN 1294 1297 and and CC 1298 1300 as as IN 1301 1314 independently independently RB 1315 1322 assayed assay VBN 1323 1325 by by IN 1326 1329 the the DT 1330 1338 activity activity NN 1339 1341 of of IN 1342 1343 a a DT 1344 1352 chimeric chimeric JJ 1353 1362 GAL4-HSF3 gal4-hsf3 NN 1363 1370 protein protein NN 1371 1373 on on IN 1374 1375 a a DT 1376 1380 GAL4 gal4 NN 1381 1389 reporter reporter NN 1390 1399 construct construct NN 1399 1400 . . . 1401 1406 These these DT 1407 1414 results result NNS 1415 1421 reveal reveal VBP 1422 1426 that that IN 1427 1431 HSF3 hsf3 NN 1432 1434 is be VBZ 1435 1445 negatively negatively RB 1446 1455 regulated regulate VBN 1456 1458 in in IN 1459 1464 avian avian JJ 1465 1470 cells cell NNS 1471 1474 and and CC 1475 1483 acquires acquire VBZ 1484 1495 DNA-binding dna-binding JJ 1496 1504 activity activity NN 1505 1507 in in IN 1508 1515 certain certain JJ 1516 1521 cells cell NNS 1522 1526 upon upon IN 1527 1531 heat heat NN 1532 1537 shock shock NN 1537 1538 . . .