Overexpression of phospholipase D prevents actinomycin D-induced apoptosis through potentiation of phosphoinositide 3-kinase signalling pathways in Chinese-hamster ovary cells.
Overexpression of phospholipase D prevents actinomycin D-induced apoptosis through potentiation of phosphoinositide 3-kinase signalling pathways in Chinese-hamster ovary cells.
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DOI：
10.1042/bj20031398
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发表时间：
2004-03
期刊：
影响因子：
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通讯作者：
M. Yamada;Y. Banno;Y. Takuwa;M. Koda;A. Harã;Y. Nozawa
中科院分区：
文献类型：
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作者：
M. Yamada;Y. Banno;Y. Takuwa;M. Koda;A. Harã;Y. Nozawa
为了研究PLD（磷脂酶D）在细胞凋亡过程调节中的作用，PLD1和PLD2在S1P3-CHO细胞[表达S1P（鞘氨醇1-磷酸）受体S1P3的CHO（中国仓鼠卵巢）细胞]中稳定过表达。用 ActD（放线菌素 D）处理 S1P3-CHO 细胞会诱导细胞凋亡，如核碎片的发生以及 PARP [聚（ADP-核糖）聚合酶] 和蛋白激酶 Cd 的 caspase 依赖性蛋白水解裂解所示。 PLD1 或 PLD2 的过表达可保护 S1P3-CHO 细胞免受 ActD 诱导的细胞凋亡，活细胞数量增加以及 PARP 和蛋白激酶 Cd 裂解的抑制证明了这一点。然而，在细胞凋亡的早期阶段，ActD 诱导 PLD 活性增加并激活细胞生存信号通路中的关键因子，例如 PI3K（磷酸肌醇 3-激酶）、Akt、p70S6K（p70 S6 激酶）和 ERK（细胞外信号调节激酶）。此外，ActD 诱导的这些生存信号酶的激活通过 PLD1 或 PLD2 的过表达而增强。 PI3K抑制剂LY294002抑制ActD诱导的Akt和p70S6K激活，并完全消除PLD1或PLD2的作用，而MEK抑制剂U0126对ERK活性的抑制作用较温和。 ActD 诱导的 p70S6K 和 ERK 激活可被 1-丁醇阻断，但不会被叔丁醇阻断；与S1P类似，外源PLD抑制ActD诱导的细胞凋亡信号通路事件。这些结果表明，在 S1P3-CHO 细胞中，PLD 表达增加可通过增强 PI3K 信号通路的激活来防止 ActD 诱导的细胞凋亡。
To examine the roles of PLD (phospholipase D) in the regulation of the apoptotic process, PLD1 and PLD2 were stably overexpressed in S1P3-CHO cells [CHO (Chinese-hamster ovary) cells expressing the S1P (sphingosine 1-phosphate) receptor S1P3]. Treatment of S1P3-CHO cells with ActD (actinomycin D) induced apoptosis, as shown by the occurrence of nuclear fragmentation and the caspase-dependent proteolytic cleavage of PARP [poly(ADP-ribose) polymerase] and protein kinase Cd. Overexpression of either PLD1 or PLD2 protected S1P3-CHO cells from ActD-induced apoptosis, as demonstrated by an increased number of viable cells and inhibition of PARP and protein kinase Cd cleavage. However, in the early phase of apoptosis, ActD induced an increase in PLD activity and activation of key factors in the cell-survival signalling pathways, such as PI3K (phosphoinositide 3-kinase), Akt, p70S6K (p70 S6 kinase) and ERK (extracellular-signal-regulated kinase). Furthermore, the ActD-induced activation of these survival signalling enzymes was potentiated by overexpression of either PLD1 or PLD2. The PI3K inhibitor LY294002 inhibited the ActD-induced activation of Akt and p70S6K, and completely abolished the effects of PLD1 or PLD2, whereas inhibition of ERK activity by the MEK inhibitor U0126 had a milder effect. The ActD-induced activation of p70S6K and ERKs was blocked by 1-butanol, but not by t-butanol; similar to S1P, exogenous PLD suppressed the ActD-induced events in the apoptosis signalling pathways. These results show that, in S1P3-CHO cells, increased expression of PLDs prevents ActD-induced apoptosis by enhanced activation of the PI3K signalling pathways.