Chen Jin-Gui
a Biosciences Division; Oak Ridge National Laboratory ; Oak Ridge , TN USA.
Plant Signal Behav. 2015;10(8):e1022013. doi: 10.1080/15592324.2015.1022013.
Receptor for Activated C Kinase 1 (RACK1) is a versatile scaffold protein that interacts with a large, diverse group of proteins to regulate various signaling cascades. RACK1 has been shown to regulate hormonal signaling, stress responses and multiple processes of growth and development in plants. However, little is known about the molecular mechanism underlying these regulations. Recently, it has been demonstrated that Arabidopsis RACK1 is phosphorylated by an atypical serine/threonine protein kinase, WITH NO LYSINE 8 (WNK8). Furthermore, RACK1 phosphorylation by WNK8 negatively regulates RACK1 function by influencing its protein stability. These findings promote a new regulatory system in which the action of RACK1 is controlled by phosphorylation and subsequent protein degradation.
活化C激酶1受体（RACK1）是一种多功能支架蛋白，它与大量不同的蛋白质相互作用，以调节各种信号级联反应。RACK1已被证明可调节植物中的激素信号传导、应激反应以及生长和发育的多个过程。然而，对于这些调节作用背后的分子机制知之甚少。最近，已经证明拟南芥RACK1被一种非典型丝氨酸/苏氨酸蛋白激酶——无赖氨酸8（WNK8）磷酸化。此外，WNK8介导的RACK1磷酸化通过影响其蛋白质稳定性对RACK1功能起负调节作用。这些发现推动了一个新的调节系统，其中RACK1的作用由磷酸化和随后的蛋白质降解控制。
