Nelsen B, Hellman L, Sen R
Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, Massachusetts 02254-9110.
Mol Cell Biol. 1988 Aug;8(8):3526-31. doi: 10.1128/mcb.8.8.3526-3531.1988.
The mouse immunoglobulin kappa light-chain enhancer can interact with at least three independent nuclear proteins. One of these proteins, NF-kappa B, is constitutively present only in nuclear extracts derived from B cells and plasma cells. A DNA-binding protein with the same sequence specificity (and therefore presumed to be NF-kappa B itself) can be induced in pre-B cells, T cells, and nonlymphoid cells by phorbol 12-acetate-13-myristate (PMA); however, it is not clear whether the induced factor can activate transcription in nonlymphoid cells as NF-kappa B does in B cells. In this paper we show that multimerization of a fragment of the mouse kappa enhancer that carried only the binding site for NF-kappa B behaved like a B-cell-specific regulatory element. Furthermore, this unit served to activate transcription in nonlymphoid cells after treatment with PMA (but not with cyclic AMP derivatives), and the kinetics of transcription activation correlated well with the kinetics of factor induction. Thus, the induced DNA-binding activity appeared to be functionally indistinguishable from that of NF-kappa B.
小鼠免疫球蛋白κ轻链增强子可与至少三种独立的核蛋白相互作用。其中一种蛋白,即核因子κB(NF-κB),仅组成性地存在于源自B细胞和浆细胞的核提取物中。一种具有相同序列特异性的DNA结合蛋白(因此推测为NF-κB本身)可被佛波醇12-乙酸盐-13-肉豆蔻酸盐(PMA)在pre-B细胞、T细胞和非淋巴细胞中诱导产生;然而,尚不清楚诱导产生的因子是否能像NF-κB在B细胞中那样在非淋巴细胞中激活转录。在本文中,我们表明,仅携带NF-κB结合位点的小鼠κ增强子片段的多聚化表现得像一个B细胞特异性调节元件。此外,该单元在用PMA(而非环磷酸腺苷衍生物)处理后可在非淋巴细胞中激活转录,且转录激活的动力学与因子诱导的动力学密切相关。因此,诱导产生的DNA结合活性在功能上似乎与NF-κB的活性没有区别。