Mårtensson A, Mårtensson I L
Department of Cell and Molecular Biology, Immunology Group, Lund University, Sweden.
Eur J Immunol. 1997 Jan;27(1):315-20. doi: 10.1002/eji.1830270145.
The pre-B cell-specific expression of the lambda5 gene is regulated at the level of transcription. The 5' region of the lambda5 gene has been shown to contain an enhancer that activates heterologous promoters. Here, we show that this enhancer, B(lambda5), also acts as a lineage- and tissue-restricted enhancer on its own promoter. We define the enhancer core, b(lambda5), that carries around 50% of the total enhancer activity. We also demonstrate that the transcription factor early B cell factor (EBF) binds to a DNA motif in the lambda5 core enhancer which is crucial for enhancer activity, suggesting that lambda5 is a second target gene of EBF.
λ5基因在前B细胞中的特异性表达是在转录水平上调控的。λ5基因的5'区域已被证明含有一个可激活异源启动子的增强子。在此，我们表明这个增强子B(λ5)在其自身启动子上也作为一个谱系和组织限制性增强子发挥作用。我们定义了增强子核心b(λ5)，它承载了约50%的总增强子活性。我们还证明转录因子早期B细胞因子(EBF)结合到λ5核心增强子中的一个DNA基序上，该基序对增强子活性至关重要，这表明λ5是EBF的第二个靶基因。
