Exosome-associated release, uptake, and neurotoxicity of HIV-1 Tat protein.
Exosome-associated release, uptake, and neurotoxicity of HIV-1 Tat protein.
复制标题
DOI：
10.1007/s13365-016-0451-6
复制
发表时间：
2016-12
影响因子：
3.2
通讯作者：
He JJ
中科院分区：
文献类型：
--
作者：
Rahimian P;He JJ
HIV-1达特是HIV基因转录和复制过程中不可缺少的反式激活因子。它已被证明作为游离蛋白质离开细胞并进入邻近细胞或与邻近细胞的表面受体相互作用以调节基因表达和细胞功能。在这项研究中，我们报告，为第一次，外泌体相关的达特的释放和摄取。使用基于HIV-1 LTR驱动的荧光素酶标记的细胞测定和蛋白质印迹法或与外泌体抑制剂、OptiPrep梯度分离和外泌体耗竭组合，我们证明了HIV-1达特在源自表达Tat的原代星形胶质细胞、Tat转染的U373.MG和293 T以及HIV感染的MT4的外泌体中的显著存在。我们进一步表明，来自表达Tat的星形胶质细胞的外泌体相关达特能够引起神经突缩短和神经元死亡，进一步支持这种新形式的细胞外达特具有生物活性。最后，我们构建了一个基本结构域缺失的达特突变体，并确定了基本结构域在达特转运到外泌体中的作用。基本结构域缺失的达特对达特转运到外泌体中没有表现出明显的影响，同时在Tat介导的LTR反式激活中保持其显性负性功能。总之，这些结果显示达特的显著部分被分泌并以外来体的形式存在，并且可能有助于细胞外达特的稳定性并拓宽其靶细胞的谱。
HIV-1 Tat is an indispensible transactivator for HIV gene transcription and replication. It has been shown to exit cells as a free protein and enter neighboring cells or interact with surface receptors of neighboring cells to regulate gene expression and cell function. In this study, we report, for the first time, exosome-associated Tat release and uptake. Using a HIV-1 LTR-driven luciferase reporter-based cell assay and Western blotting or in combination with exosome inhibitor, OptiPrep gradient fractionation, and exosome depletion, we demonstrated significant presence of HIV-1 Tat in exosomes derived from Tat-expressing primary astrocytes, Tat-transfected U373.MG and 293T, and HIV-infected MT4. We further showed that exosome-associated Tat from Tat-expressing astrocytes was capable of causing neurite shortening and neuron death, further supporting that this new form of extracellular Tat is biologically active. Lastly, we constructed a Tat mutant deleted of its basic domain and determined the role of the basic domain in Tat trafficking into exosomes. Basic domain-deleted Tat exhibited no apparent effects on Tat trafficking into exosomes, while maintained its dominant-negative function in Tat-mediated LTR transactivation. Taken together, these results show a significant fraction of Tat is secreted and present in the form of exosomes and may contribute to the stability of extracellular Tat and broaden the spectrum of its target cells.
登录
查看更多内容
影响因子：
6.4
作者：
Benelli, R;Barbero, A;Albini, A
通讯作者：
Albini, A
影响因子：
3.4
作者：
Cabezas, Sandra Columba;Federico, Maurizio
通讯作者：
Federico, Maurizio
影响因子：
3.5
作者：
Blázquez, C;Geelen, MJH;Guzmán, M
通讯作者：
Guzmán, M
影响因子：
5.4
作者：
CARROLL, R;PETERLIN, BM;DERSE, D
通讯作者：
DERSE, D
影响因子：
2.9
作者：
CHEN, LL;FRANKEL, AD;PEPINSKY, B
通讯作者：
PEPINSKY, B