In situ detection of stage-specific genes and enhancers in B cell differentiation via gene-search retroviruses.
We demonstrate that infection of an LPS-responsive pre-B cell line with transcriptionally-defective retroviruses containing a reporter gene (lacZ) can result in viral integrations where expression of lacZ is differentiation stage-dependent. Because expression of lacZ is dependent upon flanking cellular sequences these retroviral integrations represent in situ gene fusions with cellular enhancers (Enhsr1) and genes (Gensr1) which are either induced or repressed during LPS-stimulated differentiation. One of the well-documented effects of LPS upon pre-B cells is the induction of kappa light chain transcription via NF-kappa B. The identification of LPS-stimulated gene repression during B cell differentiation indicates that LPS has multiple effects upon gene expression during the pre-B to B cell transition. The identification of cellular enhancers and genes which are downregulated during the transition from the pre-B to the B cell stage indicates that other transcription factors, in addition to NF-kappa B, are required for this step in differentiation. Finally, we present some initial experiments which indicate the gene-search retroviruses can introduce expression of lacZ into normal hematopoietic cells in vitro and in vivo.
Kerr
W G
WG
Department of Genetics, Stanford University, California.
Nolan
G P
GP
Johnsen
J B
JB
Herzenberg
L A
LA
D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology* / Q000276:immunology; D002454:Cell Differentiation / Q000235:genetics; D004742:Enhancer Elements, Genetic; D015870:Gene Expression; D006410:Hematopoiesis / Q000235:genetics*; D007763:Lac Operon; D008070:Lipopolysaccharides / Q000276:immunology; D051379:Mice; D012190:Retroviridae / Q000235:genetics; D014158:Transcription, Genetic
D008070:Lipopolysaccharides