Two waves of the nuclear phospholipase C activity in serum-stimulated HL-60 cells during G(1) phase of the cell cycle.
Two waves of the nuclear phospholipase C activity in serum-stimulated HL-60 cells during G(1) phase of the cell cycle.
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细胞周期 G(1) 期期间血清刺激的 HL-60 细胞中核磷脂酶 C 活性的两波。
DOI：
10.1016/j.bbalip.2007.02.002
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
Visnjic,Dora
中科院分区：
文献类型：
--
作者：
Lukinovic-Skudar,Vesna;Matkovic,Katarina;Banfic,Hrvoje;Visnjic,Dora
磷脂酰肌醇特异性磷脂酶C（PI-PLC）在细胞周期进程中在细胞核中被激活。我们以前已经证明了在nocodazole同步化HL-60细胞核PI-PLC活性增加的两个峰值。在这项研究中，核PI-PLC的活性在血清刺激的HL-60细胞进行了研究。在血清饥饿的HL-60细胞中，在再加入血清后30 min和11 h检测到核PI-PLC活性的两个高峰，而胞浆、核膜和总细胞裂解物中的PLC活性没有平行增加。在加入血清后30 min和11 h，PI-PLCβ 1的B剪接变异体的丝氨酸磷酸化水平升高，而PI-PLCβ 1 bin核的数量无变化。PI-PLC抑制剂ET-18-OCH 3和MEK抑制剂PD 98059在两个时间点完全消除血清介导的增加。加入血清后立即或6 h加入抑制剂对进入S期的细胞数有抑制作用。这些结果表明，在细胞周期的G1期，在血清刺激的细胞中，细胞核PI-PLCβ 1b活性出现两波，并且随后PLC活性的增加对于进入S期同样重要。
Phosphatidylinositol-specific phospholipase C (PI-PLC) is activated in cell nuclei during the cell cycle progression. We have previously demonstrated two peaks of an increase in the nuclear PI-PLC activities in nocodazole-synchronized HL-60 cells. In this study, the activity of nuclear PI-PLC was investigated in serum-stimulated HL-60 cells. In serum-starved HL-60 cells, two peaks of the activity of nuclear PI-PLC were detected at 30 min and 11 h after the re-addition of serum with no parallel increase in PLC activity in cytosol, postnuclear membranes or total cell lysates. An increase in the serine phosphorylation of b splicing variant of PI-PLCβ1was detected with no change in the amount of PI-PLCβ1bin nuclei isolated at 30 min and 11 h after the addition of serum. PI-PLC inhibitor ET-18-OCH3and MEK inhibitor PD 98059 completely abolished serum-mediated increase at both time-points. The addition of inhibitors either immediately or 6 h after the addition of serum had inhibitory effects on the number of cells entering S phase. These results demonstrate that two waves of nuclear PI-PLCβ1bactivity occur in serum-stimulated cells during G1phase of the cell cycle and that the later increase in the PLC activity is equally important for the progression into the S phase.