0	10	Extinction	extinction	NN
11	13	of	of	IN
14	28	immunoglobulin	immunoglobulin	NN
29	33	gene	gene	NN
34	44	expression	expression	NN
45	47	in	in	IN
48	49	B	B	NNP
50	55	cells	cell	NNS
56	60	upon	upon	IN
61	67	fusion	fusion	NN
68	72	with	with	IN
73	77	HeLa	HeLa	NNP
78	83	cells	cell	NNS
84	86	is	be	VBZ
87	95	preceded	precede	VBN
96	98	by	by	IN
99	104	rapid	rapid	JJ
105	112	nuclear	nuclear	JJ
113	122	depletion	depletion	NN
123	125	of	of	IN
126	135	essential	essential	JJ
136	149	transcription	transcription	NN
150	157	factors	factor	NNS
158	161	and	and	CC
162	164	is	be	VBZ
165	176	accompanied	accompany	VBN
177	179	by	by	IN
180	190	widespread	widespread	JJ
191	203	inactivation	inactivation	NN
204	206	of	of	IN
207	212	genes	gene	NNS
213	222	expressed	express	VBN
223	225	in	in	IN
226	227	a	a	DT
228	229	B	B	NNP
230	243	cell-specific	cell-specific	JJ
244	250	manner	manner	NN
250	251	.	.	.

253	257	When	when	WRB
258	272	immunoglobulin	immunoglobulin	NN
273	274	(	(	(
274	276	Ig	Ig	NNP
276	277	)	)	)
278	288	expressing	express	VBG
289	290	B	b	NN
291	296	cells	cell	NNS
297	300	are	be	VBP
301	306	fused	fuse	VBN
307	311	with	with	IN
312	317	non-B	non-b	JJ
318	323	cells	cell	NNS
323	324	,	,	,
325	327	Ig	ig	NN
328	338	expression	expression	NN
339	341	is	be	VBZ
342	349	rapidly	rapidly	RB
350	360	suppressed	suppress	VBN
361	363	at	at	IN
364	367	the	the	DT
368	373	level	level	NN
374	376	of	of	IN
377	390	transcription	transcription	NN
390	391	,	,	,
392	393	a	a	DT
394	404	phenomenon	phenomenon	NN
405	411	termed	term	VBN
412	422	extinction	extinction	NN
422	423	.	.	.

424	428	Here	here	RB
429	431	we	we	PRP
432	443	demonstrate	demonstrate	VBP
444	448	that	that	IN
449	455	fusion	fusion	NN
456	458	of	of	IN
459	463	HeLa	HeLa	NNP
464	469	cells	cell	NNS
470	474	with	with	IN
475	481	either	either	CC
482	489	diploid	diploid	JJ
490	492	or	or	CC
493	503	tetraploid	tetraploid	JJ
504	505	B	B	NNP
506	511	cells	cell	NNS
512	513	(	(	(
513	518	Daudi	Daudi	NNP
518	519	)	)	)
520	527	results	result	VBZ
528	530	in	in	IN
531	541	widespread	widespread	JJ
542	552	extinction	extinction	NN
553	555	of	of	IN
556	563	several	several	JJ
564	569	other	other	JJ
570	571	B	B	NNP
572	584	cell-encoded	cell-encoded	JJ
585	590	genes	gene	NNS
591	595	that	that	WDT
596	599	are	be	VBP
600	609	expressed	express	VBN
610	612	in	in	IN
613	614	a	a	DT
615	616	B	B	NNP
617	630	cell-specific	cell-specific	JJ
631	637	manner	manner	NN
637	638	.	.	.

639	641	In	in	IN
642	650	contrast	contrast	NN
650	651	,	,	,
652	662	expression	expression	NN
663	665	of	of	IN
666	667	B	B	NNP
668	682	cell-expressed	cell-expressed	JJ
683	688	genes	gene	NNS
689	693	that	that	WDT
694	697	are	be	VBP
698	701	not	not	RB
702	711	dependent	dependent	JJ
712	714	on	on	IN
715	728	cell-specific	cell-specific	JJ
729	737	controls	control	NNS
738	740	is	be	VBZ
741	751	unaffected	unaffected	JJ
751	752	.	.	.

753	755	We	we	PRP
756	760	show	show	VBP
761	765	that	that	IN
766	769	the	the	DT
770	779	molecular	molecular	JJ
780	792	mechanism(s)	mechanism(s)	NN
793	803	underlying	underlie	VBG
804	806	Ig	Ig	NNP
807	811	gene	gene	NN
812	822	extinction	extinction	NN
823	826	can	can	MD
827	829	be	be	VB
830	839	explained	explain	VBN
839	840	,	,	,
841	843	at	at	IN
844	849	least	least	JJS
850	852	in	in	IN
853	857	part	part	NN
857	858	,	,	,
859	861	by	by	IN
862	863	a	a	DT
864	868	lack	lack	NN
869	871	of	of	IN
872	885	transcription	transcription	NN
886	893	factors	factor	NNS
894	898	that	that	WDT
899	902	are	be	VBP
903	912	essential	essential	JJ
913	916	for	for	IN
917	919	Ig	ig	NN
920	924	gene	gene	NN
925	938	transcription	transcription	NN
938	939	.	.	.

940	945	These	these	DT
946	959	transcription	transcription	NN
960	967	factors	factor	NNS
968	971	are	be	VBP
972	978	either	either	CC
979	982	not	not	RB
983	991	produced	produce	VBN
992	995	due	due	JJ
996	998	to	to	TO
999	1004	block	block	NN
1005	1007	of	of	IN
1008	1021	transcription	transcription	NN
1022	1024	of	of	IN
1025	1030	their	their	PRP$
1031	1041	respective	respective	JJ
1042	1047	genes	gene	NNS
1048	1049	(	(	(
1049	1054	Oct-2	Oct-2	NNP
1054	1055	,	,	,
1056	1061	OBF-1	OBF-1	NNP
1061	1062	,	,	,
1063	1067	PU.1	PU.1	NNP
1067	1068	)	)	)
1068	1069	,	,	,
1070	1072	or	or	CC
1073	1076	are	be	VBP
1077	1085	rendered	render	VBN
1086	1094	inactive	inactive	JJ
1095	1114	posttranslationally	posttranslationally	RB
1115	1116	(	(	(
1116	1124	NF-kappa	NF-kappa	NNP
1125	1126	B	B	NNP
1126	1127	,	,	,
1128	1131	E47	E47	NNP
1131	1132	)	)	)
1132	1133	.	.	.

1134	1136	By	by	IN
1137	1146	isolating	isolate	VBG
1147	1152	Daudi	Daudi	NNP
1153	1154	x	x	SYM
1155	1159	HeLa	HeLa	NNP
1160	1173	heterokaryons	heterokaryon	NNS
1174	1175	a	a	DT
1176	1179	few	few	JJ
1180	1185	hours	hour	NNS
1186	1191	after	after	IN
1192	1198	fusion	fusion	NN
1198	1199	,	,	,
1200	1202	we	we	PRP
1203	1207	have	have	VBP
1208	1215	studied	study	VBN
1216	1219	the	the	DT
1220	1227	initial	initial	JJ
1228	1232	fate	fate	NN
1233	1235	of	of	IN
1236	1239	two	two	CD
1240	1241	B	B	NNP
1242	1255	cell-specific	cell-specific	JJ
1256	1269	transcription	transcription	NN
1270	1277	factors	factor	NNS
1278	1286	involved	involve	VBN
1287	1289	in	in	IN
1290	1292	Ig	ig	NN
1293	1297	gene	gene	NN
1298	1311	transcription	transcription	NN
1311	1312	,	,	,
1313	1318	Oct-2	Oct-2	NNP
1319	1322	and	and	CC
1323	1331	NF-kappa	NF-kappa	NNP
1332	1334	B.	B.	NNP
1335	1339	This	this	DT
1340	1346	report	report	NN
1347	1355	provides	provide	VBZ
1356	1359	the	the	DT
1360	1365	first	first	JJ
1366	1379	demonstration	demonstration	NN
1380	1384	that	that	IN
1385	1389	upon	upon	IN
1390	1396	fusion	fusion	NN
1397	1401	with	with	IN
1402	1406	HeLa	HeLa	NNP
1407	1412	cells	cell	NNS
1412	1413	,	,	,
1414	1417	the	the	DT
1418	1425	nuclear	nuclear	JJ
1426	1434	contents	content	NNS
1435	1437	of	of	IN
1438	1439	B	B	NNP
1440	1454	cell-expressed	cell-expressed	JJ
1455	1468	transcription	transcription	NN
1469	1476	factors	factor	NNS
1477	1480	are	be	VBP
1481	1489	depleted	deplete	VBN
1490	1496	within	within	IN
1497	1498	a	a	DT
1499	1502	few	few	JJ
1503	1508	hours	hour	NNS
1509	1513	with	with	IN
1514	1522	kinetics	kinetic	NNS
1523	1527	that	that	WDT
1528	1531	are	be	VBP
1532	1534	as	as	IN
1535	1539	fast	fast	JJ
1540	1542	or	or	CC
1543	1549	faster	fast	JJR
1550	1554	than	than	IN
1555	1559	that	that	DT
1560	1562	of	of	IN
1563	1565	Ig	ig	NN
1566	1570	gene	gene	NN
1571	1581	extinction	extinction	NN
1581	1582	.	.	.

1583	1587	Thus	thus	RB
1587	1588	,	,	,
1589	1592	the	the	DT
1593	1606	extinguishing	extinguishing	NN
1607	1616	mechanism	mechanism	NN
1617	1619	is	be	VBZ
1620	1629	effective	effective	JJ
1630	1634	very	very	RB
1635	1640	early	early	RB
1641	1646	after	after	IN
1647	1653	fusion	fusion	NN
1653	1654	.	.	.

1655	1657	We	we	PRP
1658	1665	suggest	suggest	VBP
1666	1670	that	that	IN
1671	1681	extinction	extinction	NN
1682	1684	of	of	IN
1685	1687	Ig	ig	NN
1688	1693	genes	gene	NNS
1694	1696	is	be	VBZ
1697	1701	part	part	NN
1702	1704	of	of	IN
1705	1706	a	a	DT
1707	1713	global	global	JJ
1714	1723	mechanism	mechanism	NN
1724	1728	that	that	WDT
1729	1739	suppresses	suppress	VBZ
1740	1743	the	the	DT
1744	1759	differentiation	differentiation	NN
1760	1767	program	program	NN
1768	1775	foreign	foreign	JJ
1776	1778	to	to	TO
1779	1782	the	the	DT
1783	1787	HeLa	HeLa	NNP
1788	1797	phenotype	phenotype	NN
1797	1798	.	.	.