DC-SIGN启动子活化信号通路对HIV-15’LTR活性的影响

The effects of signaling pathways activating DC-SIGN promoter on the activity of HIV-1 5＇LTR

目的研究诱导DC-SIGN启动子活化的信号通路对HIV-15’LTR活性的影响。方法PCR法扩增DC-SIGN启动子及HIV-15’LTR序列，通过双酶切重组到荧光素酶报告质粒中，构建DC-SIGN启动子和HIV-15’LTR荧光素酶报告质粒。以PMA分化的THP-1细胞作为细胞模型，分别转染DC-SIGN启动子和HIV-15’LTR荧光素酶报告质粒，并以相应的信号通路阻断剂处理，以1000IU／ml的IL-4诱导24h后检测荧光素酶活性。结果HIV-15’LTR荧光素酶报告质粒的活性明显弱于DC-SIGN启动子，IL-4诱导可以使DC-SIGN启动子和HIV-15’LTR荧光素酶报告质粒的活性升高至2倍以上。ERK、JAK-STAT和NF-KB信号通路阻断剂均能够降低DC-SIGN启动子荧光素酶报告质粒的活性，其中ERKl／2抑制剂抑制活性最强，几乎完全阻断了IL-4的诱导效应。对于HIV-15‘LTR荧光素酶报告质粒，NF-κB信号通路阻断剂阻断效果最明显，阻断效率为52．32％，ERK信号通路阻断剂阻断效率为43．31％。结论IL-4诱导的信号通路在活化DC-SIGN启动子的同时，对HIV-15’LTR也具有一定的活化作用，并主要通过NF-κB和ERK信号通路实现。

Objective To explore the effects of signaling pathways inducing activation of DC-SIGN promoter on the activity of HIV-1 5＇LTR. Methods The sequences of DC-SIGN promoter and HIV-1 5＇LTR were amplified by PCR and then cloned into pGL-3/Basic plasmid to constructluciferase reporter plasmids for DC-SIGN promoter and HIV-1 5＇LTR. Differentiated THP-1 cells stimulated by PMA （phorbol myristate ac- etate） were used as the in vitro model of DCs. The activaties of DC-SIGN promoter and HIV-1 5＇LTR in- duced by IL-4 in differentiated THP-1 cells were studied using lueiferase reporter plasmids. The signaling pathways were identified by using specific inhibitors. Results IL-4 induced signaling pathways could in- crease the activities of HIV-1 5＇LTR and DC-SIGN promoter for more than two times in THP-1 cells trans- fected with luciferase reporter plasmids. However, the activity of HIV-1 5 ＇LTR was weaker than that of DC- SIGN promoter. ERK/JAK-STAT/NF-κB signal pathway blockers could inhibit the luciferase activity driven by DC-SIGN promoter, of which ERK1/2 blocker showed the strongest inhibitory effect that almost complete- ly blocked IL-4 induction, NF-KB blocker had a significant inhibitory effect on HIV-1 5＇LTR activity at a rate of 52.32% , followed by the ERK blocker at a rate of 43.31%, Conclusion This study suggested that IL-4-induced signaling pathways mediate the activation of DC-SIGN promoter and HIV-1 5＇LTR through NF- κB and ERK.