Involvement of c-Jun NH 2 -terminal kinase-1 in heat-induced apoptotic cell death of human monoblastic leukaemia U937 cells
Involvement of c-Jun NH 2 -terminal kinase-1 in heat-induced apoptotic cell death of human monoblastic leukaemia U937 cells
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c-Jun NH 2 -末端激酶1参与热诱导人单核细胞白血病U937细胞凋亡
DOI：
10.1080/09553000110062512
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发表时间：
2001
影响因子：
2.6
通讯作者：
Y. Hosoi
中科院分区：
文献类型：
--
作者：
A. Enomoto;N. Suzuki;C. Liu;Y. Kang;J. Zhu;S. Serizawa;Y. Matsumoto;A. Morita;M. Ito;Y. Hosoi
目的：目的探讨热诱导人单核细胞白血病U937细胞凋亡过程中JNK-1（c-Jun NH 2 -terminal kinase-1，JNK-1）和HSP 2 7的作用。材料与方法：显性负性JNK 1（APF）在U937细胞中过表达，其中磷酸化位点Thr-Pro-Tyr改变为Ala-Pro-Phe。分别通过赤藓红-B染料排斥试验和琼脂糖凝胶电泳分析细胞活力和DNA片段化。Western blotting检测活化caspase-9、磷酸化JNK 1、JNK 2、p38和HSP 27的表达。还使用c-Jun作为底物进行JNK 1激酶测定。结果如下：44° C高温后U937细胞活力迅速丧失，caspase-9裂解形式活化，DNA断裂，而显性负性JNK 1过表达干扰JNK 1的磷酸化或活化，而不影响JNK 2或p38/SAPK的磷酸化或活化，并明显延迟或减少caspase-9的裂解和活化，DNA断裂和细胞死亡。在亲本U937细胞中观察到的热诱导的HSP 27磷酸化被抑制，并且在jnk 1突变细胞中仅轻微检测到。结论：JNK 1的长期磷酸化或激活被认为在热诱导的细胞凋亡中是重要的，JNK 1可能通过磷酸化HSP 27和激活caspase-9来控制该过程。
Purpose: To determine the involvement of c-Jun NH 2 -terminal kinase-1 (JNK1) and possibly of HSP27 in heat-induced apoptosis of human monoblastic leukaemia U937 cells. Materials and methods: Dominant negative JNK1 (APF), in which the phosphorylation sites Thr-Pro-Tyr were changed to Ala-Pro-Phe, was overexpressed in U937 cells. Cell viability and DNA fragmentation were analysed by the erythrosin-B dye exclusion test and by agarose gel electrophoresis, respectively. Expression of activated caspase-9, phosphorylated JNK1, JNK2, p38 and HSP27 was examined by Western blotting. JNK1 kinase assay was also performed using c-Jun as a substrate. Results: Loss of viability, activated cleavage form of caspase-9 and DNA fragmentation were rapid in U937 cells after 44°;C hyperthermia, while overexpression of dominant negative JNK1 interfered with phosphorylation or activation of JNK1 without affecting that of JNK2 or p38/SAPK, and apparently delayed or reduced cleavage and activation of caspase-9, DNA fragmentation and cell death. Heat-induced phosphorylation of HSP27, observed in parental U937 cells, was suppressed and only slightly detectable in jnk1 mutant cells. Conclusions: Prolonged phosphorylation or activation of JNK1 was considered important for heat-induced apoptosis and JNK1 may control the process possibly through phosphorylation of HSP27 and caspase-9 activation in U937 cells.