Entecavir competitively inhibits deoxyguanosine and deoxyadenosine phosphorylation in isolated mitochondria and the perfused rat heart.
Entecavir competitively inhibits deoxyguanosine and deoxyadenosine phosphorylation in isolated mitochondria and the perfused rat heart.
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DOI：
10.1016/j.jbc.2022.101876
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发表时间：
2022-05
影响因子：
4.8
通讯作者：
McKee, Edward E.
中科院分区：
文献类型：
--
作者：
Ward, Avery S.;Hsiung, Chia-Heng;Kesterson, Daniel G.;Kamath, Vasudeva G.;McKee, Edward E.
据报道，脱氧鸟苷激酶（dGK）在线粒体嘌呤回收途径中负责脱氧腺苷（dA）和脱氧鸟苷（dG）的磷酸化。抗病毒核苷类似物被称为核苷逆转录酶抑制剂（NRTIs），它必须被宿主酶磷酸化才能变得有活性。我们提出NRTI嘌呤类似物可能是dGK的竞争性抑制剂的可能性。从一组这样的类似物中，我们证明恩替卡韦（ETV）竞争性地抑制大鼠线粒体中dG和dA的磷酸化。来自大脑、心脏、肾脏和肝脏的线粒体明显倾向于磷酸化dG而不是dA（10 - 30倍）和ETV而不是dA（2.5 - 4倍）。研究发现，ETV抑制dG磷酸化的IC50值为15.3±2.2 μM， ETV和dG都是dA磷酸化的有效抑制剂，IC50值分别为0.034±0.007和0.028±0.006 μM。此外，dG和ETV的磷酸化遵循Michaelis-Menten动力学，各自竞争性地抑制对方的磷酸化。我们观察到dA磷酸化的动力学与dG磷酸化的动力学明显不同，对dGK的亲和力呈指数级降低，dA对dG或ETV的磷酸化没有影响。最后，在离体心脏灌注模型中，我们证明dG、dA和ETV被磷酸化，并且ETV抑制dG磷酸化。综上所述，这些数据表明dGK受到ETV的抑制，dGK的主要作用是磷酸化dG而不是磷酸化dA。
Deoxyguanosine kinase (dGK) is reported responsible for the phosphorylation of deoxyadenosine (dA) and deoxyguanosine (dG) in the mitochondrial purine salvage pathway. Antiviral nucleoside analogs known as nucleoside reverse transcriptase inhibitors (NRTIs) must be phosphorylated by host enzymes for the analog to become active. We address the possibility that NRTI purine analogs may be competitive inhibitors of dGK. From a group of such analogs, we demonstrate that entecavir (ETV) competitively inhibited the phosphorylation of dG and dA in rat mitochondria. Mitochondria from the brain, heart, kidney, and liver showed a marked preference for phosphorylation of dG over dA (10–30-fold) and ETV over dA (2.5–4-fold). We found that ETV inhibited the phosphorylation of dG with an IC50 of 15.3 ± 2.2 μM and that ETV and dG were both potent inhibitors of dA phosphorylation with IC50s of 0.034 ± 0.007 and 0.028 ± 0.006 μM, respectively. In addition, the phosphorylation of dG and ETV followed Michaelis–Menten kinetics and each competitively inhibited the phosphorylation of the other. We observed that the kinetics of dA phosphorylation were strikingly different from those of dG phosphorylation, with an exponentially lower affinity for dGK and no effect of dA on dG or ETV phosphorylation. Finally, in an isolated heart perfusion model, we demonstrated that dG, dA, and ETV were phosphorylated and dG phosphorylation was inhibited by ETV. Taken together, these data demonstrate that dGK is inhibited by ETV and that the primary role of dGK is in the phosphorylation of dG rather than dA.
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影响因子：
11.1
作者：
Garone C;Garcia-Diaz B;Emmanuele V;Lopez LC;Tadesse S;Akman HO;Tanji K;Quinzii CM;Hirano M
通讯作者：
Hirano M
影响因子：
4.8
作者：
PODZUWEIT, T;NENNSTIEL, P;MULLER, A
通讯作者：
MULLER, A
影响因子：
4.7
作者：
McCann KA;Williams DW;McKee EE
通讯作者：
McKee EE
影响因子：
3.8
作者：
Bulst, Stefanie;Holinski-Feder, Elke;Horvath, Rita
通讯作者：
Horvath, Rita
影响因子：
3.5
作者：
Bulst, Stefanie;Abicht, Angela;Horvath, Rita
通讯作者：
Horvath, Rita