Immunoglobulin beta signaling regulates locus accessibility for ordered immunoglobulin gene rearrangements.
J Exp Med
; 191(8): 1333-40, 2000 Apr 17.
Article
em En
| MEDLINE
| ID: mdl-10770800
ABSTRACT
The antigen receptor gene rearrangement at a given locus is tightly regulated with respect to cell lineage and developmental stage by an ill-defined mechanism. To study the possible role of precursor B cell antigen receptor (pre-BCR) signaling in the regulation of the ordered immunoglobulin (Ig) gene rearrangement during B cell differentiation, a newly developed system using mu heavy (H) chain membrane exon (microm)-deficient mice was employed. In this system, the antibody-mediated cross-linking of Igbeta on developmentally arrested progenitor B (pro-B) cells mimicked pre-BCR signaling to induce early B cell differentiation in vivo. Analyses with ligation-mediated polymerase chain reaction revealed that the Igbeta cross-linking induced the redirection of Ig gene rearrangements, namely, the suppression of ongoing rearrangements at the H chain locus and the activation of rearrangements at the light (L) chain locus. Upon the cross-linking, the kappaL chain germline transcription was found to be upregulated whereas the V(H) germline transcription was promptly downregulated. Notably, this alteration of the accessibility at the H and L chain loci was detected even before the induction of cellular differentiation became detectable by the change of surface phenotype. Thus, the pre-BCR signaling through Igbeta appears to regulate the ordered Ig gene rearrangement by altering the Ig locus accessibility.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Linfócitos B
/
Receptores de Antígenos de Linfócitos B
/
Rearranjo Gênico de Cadeia Pesada de Linfócito B
Limite:
Animals
Idioma:
En
Ano de publicação:
2000
Tipo de documento:
Article