Lopinavir impairs protein synthesis and induces eEF2 phosphorylation via the activation of AMP-activated protein kinase.
Lopinavir impairs protein synthesis and induces eEF2 phosphorylation via the activation of AMP-activated protein kinase.
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DOI：
10.1002/jcb.21882
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发表时间：
2008-10-15
影响因子：
4
通讯作者：
Lang, Charles H.
中科院分区：
文献类型：
--
作者：
Hong-Brown, Ly Q.;Brown, C. Randell;Huber, Danuta S.;Lang, Charles H.
艾滋病毒抗逆转录病毒药物减少蛋白质合成，尽管这一过程的基本调控机制尚未完全建立。因此，我们研究了HIV蛋白酶抑制剂洛匹那韦（LPV）对蛋白质代谢的影响。我们还表征了介导这种药物对延伸因子-2（eEF 2）（翻译机制的关键组成部分）的作用的机制。用LPV处理C2 C12心肌细胞对蛋白质合成产生剂量依赖性抑制作用。在15 min时观察到该效应，并维持至少4 h。从机制上讲，LPV增加了eEF 2的磷酸化，从而降低了该蛋白的活性。eEF 2磷酸化水平的增加与其上游调节因子AMP活化蛋白激酶（AMPK）和eEF 2激酶（eEF 2K）活性的增加有关。AMPK和eEF 2K在体外激酶测定中直接磷酸化eEF 2，表明两种不同的途径导致eEF 2磷酸化。为了验证这种联系，用AMPK抑制剂化合物C处理肌细胞。化合物C阻断eEF 2K和eEF 2磷酸化，表明LPV通过AMPK-eEF 2K依赖性途径影响eEF 2活性。与此相反，与rottlerin孵育的心肌细胞抑制eEF 2K，但不eEF 2磷酸化，这表明eEF 2可以调节独立的eEF 2K。最后，当eEF 2或肽用作底物时，LPV不影响PP 2A活性。总的来说，这些结果表明，LPV通过抑制eEF 2至少部分地降低蛋白质合成。这似乎是由AMPK调节的，AMPK可以直接作用于eEF 2或通过eEF 2K的作用间接作用。
HIV anti-retroviral drugs decrease protein synthesis, although the underlying regulatory mechanisms of this process are not fully established. Therefore, we investigated the effects of the HIV protease inhibitor lopinavir (LPV) on protein metabolism. We also characterized the mechanisms that mediate the effects of this drug on elongation factor-2 (eEF2), a key component of the translational machinery. Treatment of C2C12 myocytes with LPV produced a dose-dependent inhibitory effect on protein synthesis. This effect was observed at 15 min and was maintained for at least 4 h. Mechanistically, LPV increased the phosphorylation of eEF2 and thereby decreased the activity of this protein. Increased phosphorylation of eEF2 was associated with increased activity of its upstream regulators AMP-activated protein kinase (AMPK) and eEF2 kinase (eEF2K). Both AMPK and eEF2K directly phosphorylated eEF2 in an in vitro kinase assay suggesting two distinct paths lead to eEF2 phosphorylation. To verify this connection, myocytes were treated with the AMPK inhibitor compound C. Compound C blocked eEF2K and eEF2 phosphorylation, demonstrating that LPV affects eEF2 activity via an AMPK-eEF2K dependent pathway. In contrast, incubation of myocytes with rottlerin suppressed eEF2K, but not eEF2 phosphorylation, suggesting that eEF2 can be regulated independent of eEF2K. Finally, LPV did not affect PP2A activity when either eEF2 or peptide was used as the substrate. Collectively, these results indicate that LPV decreases protein synthesis, at least in part, via inhibition of eEF2. This appears regulated by AMPK which can act directly on eEF2 or indirectly via the action of eEF2K.
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DOI：
10.1097/00126334-200308150-00007
发表时间：
2003-08-15
影响因子：
3.6
作者：
Gutiérrez, F;Padilla, S;Martin-Hidalgo, A
通讯作者：
Martin-Hidalgo, A
影响因子：
4.8
作者：
Browne, GJ;Finn, SG;Proud, CG
通讯作者：
Proud, CG
影响因子：
4.8
作者：
Jain, RG;Lenhard, JM
通讯作者：
Lenhard, JM
影响因子：
1.5
作者：
Hong-Brown, LQ;Brown, CR;Lang, CH
通讯作者：
Lang, CH
影响因子：
11.8
作者：
Mangili, A;Murman, DH;Wanke, CA
通讯作者：
Wanke, CA