A novel enhancer in the immunoglobulin lambda locus is duplicated and functionally independent of NF kappa B.

摘要: As a first step toward defining the elements necessary for lambda immunoglobulin gene regulation, DNase I hypersensitive sites were mapped in mouse locus. A site found 15.5 kb downstream of C 4 was present all B-cell but not T-cell lines tested. This coincided with strong B-cell-specific transcriptional enhancer (E 2-4). novel is active myeloma cells, regardless status endogenous genes, inactive line and fibroblasts. The E 2-4 functions absence transcription factor NF kappa B, which function. No evidence could be B binding by this element. Rearrangement V 2 to JC 3 or genes deletes 2-4; however, second 35 1, cannot eliminated rearrangements. 3-1) 90% homologous sequence region determined comprise likewise lacks consensus B. data support model independent activation expression based on locus-specific regulation at level.