College of Veterinary Medicine, Northwest A&F University, Yangling, 712100, Shaanxi, China.
College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, Shaanxi, China.
J Mol Histol. 2018 Oct;49(5):519-530. doi: 10.1007/s10735-018-9790-3. Epub 2018 Aug 20.
During the development of mammalian cortex, late neurons generated by neuronal progenitors bypass earlier-born neurons and migrate to reach upper layers of cortical plate in an inner-to-outer fashion. Filamentous-actin (F-actin) can regulate neuronal migration, whereas Coactosin-like protein 1 (Cotl1) modulates F-actin. Lys 75 and Arg 73 of Cotl1 play an important role in binding F-actin; when they are mutated to Glu, Cotl1 cannot bind F-actin, called as a non-actin-binding mutant (ABM). The Lys 131 site of Cotl1, the 5-Lipoxygenase (5LO) binding site, is spatially close to Lys 75, leading to impact the binding of Cotl1 to F-actin. When Lys 131 is mutated to Ala (K131A), Cotl1 cannot bind to 5LO. We have demonstrated that overexpression of Cotl1 inhibited neuronal migration and increased the length of neuronal leading processes. To further explore cellular and molecular mechanisms of Cotl1's effect on neuronal migration, we constructed two mutant vectors-Cotl1-ABM and Cotl1-K131A and studied using in utero electroporation and primary neuronal culture technique. Results indicated that in the Cotl1-ABM group, the neuronal migration and length of the leading process both recovered as control neurons at the postnatal day 1 (P1), while in the Cotl1-K131A group, numerous neurons remained in deeper layers of cortical plate or intermediate zone. However, at P7, most Cotl1-K131A transfected neurons reached their destination. Moreover, we found that overexpression of Cotl1 inhibited the proliferation and mitotic activity of NPs. Therefore, These results demonstrated that Cotl1 played an important role in mouse neocortical development.
在哺乳动物大脑皮层发育过程中，神经元前体细胞产生的晚期神经元会绕过早期神经元，并以内到外的方式迁移到皮质板的上层。丝状肌动蛋白（F-actin）可以调节神经元迁移，而 Coactosin-like protein 1（Cotl1）则调节 F-actin。Cotl1 的赖氨酸 75 和精氨酸 73 对 F-actin 的结合起着重要作用；当它们突变为谷氨酸时，Cotl1 无法与 F-actin 结合，称为非肌动蛋白结合突变体（ABM）。Cotl1 的赖氨酸 131 位点是 5-脂氧合酶（5LO）的结合位点，空间上靠近赖氨酸 75，导致 Cotl1 与 F-actin 的结合受到影响。当赖氨酸 131 突变为丙氨酸（K131A）时，Cotl1 无法与 5LO 结合。我们已经证明，Cotl1 的过表达抑制了神经元迁移并增加了神经元突起的长度。为了进一步探讨 Cotl1 对神经元迁移的影响的细胞和分子机制，我们构建了两个突变载体-Cotl1-ABM 和 Cotl1-K131A，并使用子宫内电穿孔和原代神经元培养技术进行了研究。结果表明，在 Cotl1-ABM 组中，神经元迁移和突起的长度在出生后第 1 天（P1）均恢复到对照神经元的水平，而在 Cotl1-K131A 组中，许多神经元仍留在皮质板的深层或中间层。然而，在 P7 时，大多数 Cotl1-K131A 转染的神经元到达了目的地。此外，我们发现 Cotl1 的过表达抑制了 NPs 的增殖和有丝分裂活性。因此，这些结果表明 Cotl1 在小鼠新皮层发育中起着重要作用。
