Diacylglycerol promotes centrosome polarization in T cells via reciprocal localization of dynein and myosin II
Diacylglycerol promotes centrosome polarization in T cells via reciprocal localization of dynein and myosin II
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DOI：
10.1073/pnas.1306180110
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发表时间：
2013-07-16
影响因子：
11.1
通讯作者：
Huse, Morgan
中科院分区：
文献类型：
--
作者：
Liu, Xin;Kapoor, Tarun M.;Huse, Morgan
中心体向免疫突触的重定向通过促进细胞因子和细胞溶解因子向抗原呈递细胞的定向释放来维持T细胞效应器功能的特异性。这种极化反应是由二酰基甘油的局部积累驱动的，二酰基甘油将多种蛋白激酶（PK）C同工酶募集到突触膜。在这里，我们使用T细胞受体（TCR）的光活化和成像方法来证明，PKC控制中心体动力学通过相互定位的两个电机复合物，动力蛋白和非肌肉肌球蛋白（NM）II。动力蛋白聚集在TCR刺激区域，而匪II聚集在细胞后部，在极化中心体后面。PKC活性，形成动力蛋白和匪II积累在这个框架内，控制匪II本地化直接通过磷酸化抑制位点内的肌球蛋白调节轻链，从而抑制匪II聚集在该地区的TCR刺激。同时，肌球蛋白调节轻链内不同位点的磷酸化Rho激酶驱动NMII聚集在中心体后面的区域。这些结果揭示了NMII在T细胞极性中的作用，并证明了它是如何受上游信号调节的。
Centrosome reorientation to the immunological synapse maintains the specificity of T-cell effector function by facilitating the directional release of cytokines and cytolytic factors toward the antigen-presenting cell. This polarization response is driven by the localized accumulation of diacylglycerol, which recruits multiple protein kinase (PK)C isozymes to the synaptic membrane. Here, we used T-cell receptor (TCR) photoactivation and imaging methodology to demonstrate that PKCs control centrosome dynamics through the reciprocal localization of two motor complexes, dynein and nonmuscle myosin (NM)II. Dynein accumulated in the region of TCR stimulation, whereas NMII clustered in the back of the cell, behind the polarizing centrosome. PKC activity, which shaped both dynein and NMII accumulation within this framework, controlled NMII localization directly by phosphorylating inhibitory sites within the myosin regulatory light chain, thereby suppressing NMII clustering in the region of TCR stimulation. Concurrently, phosphorylation of distinct sites within myosin regulatory light chain by Rho kinase drove NMII clustering in areas behind the centrosome. These results reveal a role for NMII in T-cell polarity and demonstrate how it is regulated by upstream signals.