Rac1 is a small GTPase of the Rho family. A previous study showed that the activation of Rac1 had an opposing effect on induction and maintenance of long-term potentiation (LTP) in the hippocampus. However, the molecular mechanism underlying this opposing effect remains to be addressed. In the present work, we find that the activation of Rac1 during the induction of LTP leads to an activation of PKCι/λ by phosphatidylinositol-3-kinase (PI3K), whereas the activation of Rac1 during the maintenance of LTP leads to the inhibition of PKMζ by LIM_kinase (LIMK) in the hippocampus. This result suggests that during different stages of LTP, the activation of Rac1 can modulate different signaling pathways, which leads to an opposing effect on the induction and maintenance of LTP in the hippocampus.

中文翻译：

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通过作用于不同的激酶，Rac1 的激活对海马体长期增强的诱导和维持具有相反的作用。

Rac1 是 Rho 家族的一个小 GTPase。之前的一项研究表明，Rac1 的激活对海马体中长时程增强 (LTP) 的诱导和维持具有相反的影响。然而，这种相反效应背后的分子机制仍有待解决。在目前的工作中，我们发现在 LTP 诱导过程中 Rac1 的激活导致 PKCι/λ 被磷脂酰肌醇 3-激酶 (PI3K) 激活，而在 LTP 维持过程中 Rac1 的激活导致抑制PKMζ 由海马中的 LIM_kinase (LIMK) 产生。该结果表明，在LTP的不同阶段，Rac1的激活可以调节不同的信号通路，从而对海马LTP的诱导和维持产生相反的作用。