Günzburg W H, Heinemann F, Wintersperger S, Miethke T, Wagner H, Erfle V, Salmons B
GSF-Research Centre for Environment and Health, Institute of Molecular Virology, Oberschleissheim, Germany.
Nature. 1993 Jul 8;364(6433):154-8. doi: 10.1038/364154a0.
Endogenous superantigens are encoded by the open reading frame contained within the mouse mammary tumour virus long terminal repeat (MMTV LTR). Superantigen expression results in T-cell proliferation and, during early ontogeny, T-cell deletion. Here we identify a novel promoter located upstream of the previously described MMTV promoter. Transcripts from this promoter initiate within the U3 region of the MMTV LTR and splice to the acceptor for endogenous superantigen coding region. The novel U3 promoter is active in B lymphocytes, which are cognate antigen-presenting cells for endogenous superantigen, and is able to direct expression of superantigen in the absence of the previously described MMTV promoter.
内源性超抗原由小鼠乳腺肿瘤病毒长末端重复序列（MMTV LTR）中的开放阅读框编码。超抗原表达导致T细胞增殖，并且在个体发育早期导致T细胞缺失。在此，我们鉴定出一个位于先前描述的MMTV启动子上游的新型启动子。来自该启动子的转录本在MMTV LTR的U3区域内起始，并剪接到内源性超抗原编码区的受体。这种新型U3启动子在B淋巴细胞中具有活性，B淋巴细胞是内源性超抗原的同源抗原呈递细胞，并且能够在不存在先前描述的MMTV启动子的情况下指导超抗原的表达。
