Mutations at tyrosine 88, lysine 92 and tyrosine 470 of human dopamine transporter result in an attenuation of HIV-1 Tat-induced inhibition of dopamine transport.
Mutations at tyrosine 88, lysine 92 and tyrosine 470 of human dopamine transporter result in an attenuation of HIV-1 Tat-induced inhibition of dopamine transport.
复制标题
DOI：
10.1007/s11481-015-9583-3
复制
发表时间：
2015-03
影响因子：
6.2
通讯作者：
Zhu, Jun
中科院分区：
文献类型：
--
作者：
Midde, Narasimha M.;Yuan, Yaxia;Quizon, Pamela M.;Sun, Wei-Lun;Huang, Xiaoqin;Zhan, Chang-Guo;Zhu, Jun
HIV-1转录反式激活因子（达特）蛋白通过抑制多巴胺转运蛋白（DAT）功能破坏多巴胺（DA）神经传递，导致HIV-1感染个体的神经认知损害增加。通过综合计算模型和药理学研究，我们已经证明，酪氨酸470（Y 470 H）的突变的人DAT（hDAT）减弱Tat诱导的抑制DA摄取通过改变转运蛋白的构象转换。本研究探讨了酪氨酸470（Y 470 F和Y 470 A）和酪氨酸88（Y88 F）和赖氨酸92（K92 M），达特结合hDAT的其他相关残基的其他取代的功能影响，在塔特诱导的抑制作用对DA转运。Y88 F、K92 M和Y 470 A减弱Tat诱导的DA转运抑制，暗示这些残基与达特结合hDAT的功能相关性。与野生型hDAT相比，Y 470 A和K92 M降低了[3 H]DA摄取的最大速度，而Y88 F没有改变Km。Y88 F和K92 M增强DA抑制[3 H]DA摄取和[3 H] WIN 35，428结合的IC 50值，但降低可卡因和GBR 12909抑制[3 H]DA摄取的IC 50，表明这些残基对于底物和这些抑制剂是关键的。Y 470 F、Y 470 A、Y88 F和K92 M减弱锌诱导的[3 H] WIN 35，428结合的增加。此外，只有Y 470 A和K92 M增强DA流出相对于野生型hDAT，这表明这些残基的突变差异调节转运蛋白构象转换。这些结果证明Tyr 88和Lys 92沿着Tyr 470作为hDAT中用于Tat诱导的DA转运抑制的功能性识别残基，并且提供了对鉴定DAT上用于达特结合的靶残基的机理见解。
HIV-1 transactivator of transcription (Tat) protein disrupts the dopamine (DA) neurotransmission by inhibiting DA transporter (DAT) function, leading to increased neurocognitive impairment in HIV-1 infected individuals. Through integrated computational modeling and pharmacological studies, we have demonstrated that mutation of tyrosine470 (Y470H) of human DAT (hDAT) attenuates Tat-induced inhibition of DA uptake by changing the transporter conformational transitions. The present study examined the functional influences of other substitutions at tyrosine470 (Y470F and Y470A) and tyrosine88 (Y88F) and lysine92 (K92M), two other relevant residues for Tat binding to hDAT, in Tat-induced inhibitory effects on DA transport. Y88F, K92M and Y470A attenuated Tat-induced inhibition of DA transport, implicating the functional relevance of these residues for Tat binding to hDAT. Compared to wild type hDAT, Y470A and K92M but not Y88F reduced the maximal velocity of [3H]DA uptake without changes in the Km. Y88F and K92M enhanced IC50 values for DA inhibition of [3H]DA uptake and [3H]WIN35,428 binding but decreased IC50 for cocaine and GBR12909 inhibition of [3H]DA uptake, suggesting that these residues are critical for substrate and these inhibitors. Y470F, Y470A, Y88F and K92M attenuated zinc-induced increase of [3H]WIN35,428 binding. Moreover, only Y470A and K92M enhanced DA efflux relative to wild type hDAT, suggesting mutations of these residues differentially modulate transporter conformational transitions. These results demonstrate Tyr88 and Lys92 along with Tyr470 as functional recognition residues in hDAT for Tat-induced inhibition of DA transport and provide mechanistic insights into identifying target residues on the DAT for Tat binding.
登录
查看更多内容
影响因子：
5.7
作者：
Chang, Linda;Wang, Gene-Jack;Fowler, Joanna S.
通讯作者：
Fowler, Joanna S.
影响因子：
3.2
作者：
Hudson, L;Liu, JK;Everall, I
通讯作者：
Everall, I
影响因子：
11.2
作者：
McArthur, Justin C.;Steiner, Joseph;Nath, Avi
通讯作者：
Nath, Avi
影响因子：
5.3
作者：
Bertrand, Sarah J.;Aksenova, Marina V.;Mactutus, Charles F.;Booze, Rosemarie M.
通讯作者：
Booze, Rosemarie M.
影响因子：
3.6
作者：
Harrod, S. B.;Mactutus, C. F.;Booze, R. M.
通讯作者：
Booze, R. M.