Changes in replication, nuclear location, and expression of the Igh locus after fusion of a pre-B cell line with a T cell line.
J Immunol
; 175(4): 2317-20, 2005 Aug 15.
Article
em En
| MEDLINE
| ID: mdl-16081801
ABSTRACT
We have previously observed that replication and nuclear location of the murine Igh locus are developmentally regulated during B cell differentiation. In non-B, B, and plasma cells, sequences near the 3' end of the Igh locus replicate early in S while upstream Vh sequences replicate late in S, and the Igh locus is located near the nuclear periphery. In fact, in MEL non-B cells, replication of a 500-kb segment containing Igh-C and flanking sequences occurs progressively later throughout S by 3' to 5' unidirectional fork movement. In contrast, in pro- and pre-B cells, the entire 3-Mb Igh locus is located away from the nuclear periphery and replicates early in S by forks progressing in both directions. In this study, using an 18-81 (pre-B) x BW5147 (T) cell fusion system in which Igh expression is extinguished, we found that in all Igh alleles, Vh sequences replicated later in S than 3' Igh sequences (similar to that detected in BW5147), but the Igh locus was situated away from the nuclear periphery (similar to that observed in 18-81). Thus, pre-B cell-derived Igh genes had changes in replication timing, but not in nuclear location, whereas T cell-derived Igh genes changed their nuclear location but not their replication timing. These data are consistent with the silencing of a pre-B cell-specific replication program in the fusion hybrid cells and independent regulation of the nuclear location of Igh loci.
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Células-Tronco Hematopoéticas
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Linfócitos B
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Linfócitos T
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Núcleo Celular
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Cadeias Pesadas de Imunoglobulinas
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Replicação do DNA
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Células Híbridas
Limite:
Animals
Idioma:
En
Revista:
J Immunol
Ano de publicação:
2005
Tipo de documento:
Article
País de afiliação:
Estados Unidos