Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences of Chinese Academy of Sciences and Shanghai Jiao Tong University School of Medicine, Shanghai, China.
PLoS One. 2009 Sep 4;4(9):e6916. doi: 10.1371/journal.pone.0006916.
Palladin is an actin cytoskeleton-associated protein which is crucial for cell morphogenesis and motility. Previous studies have shown that palladin is localized to the axonal growth cone in neurons and may play an important role in axonal extension. Previously, we have generated palladin knockout mice which display cranial neural tube closure defect and embryonic lethality before embryonic day 15.5 (E15.5). To further study the role of palladin in the developing nervous system, we examined the innervation of palladin-deficient mouse embryos since the 200 kd, 140 kd, 90-92 kd and 50 kd palladin isoforms were undetectable in the mutant mouse embryo brain. Contrary to the results of previous studies, we found no inhibition of the axonal extension in palladin-deficient mouse embryos. The cortical neurons derived from palladin-deficient mice also showed no significant difference in neurite outgrowth as compared with those from wild-type mice. Moreover, no difference was found in neurite outgrowth of neural stem cell derived-neurons between palladin-deficient mice and wild-type mice. In conclusion, these results suggest that palladin is dispensable for normal neurite outgrowth in mice.
帕拉丁是一种与肌动蛋白细胞骨架相关的蛋白，对于细胞形态发生和运动至关重要。先前的研究表明，帕拉丁定位于神经元中的轴突生长锥，可能在轴突延伸中发挥重要作用。先前，我们已经生成了帕拉丁敲除小鼠，这些小鼠表现出颅神经管闭合缺陷，并在胚胎第 15.5 天（E15.5）之前出现胚胎致死。为了进一步研究帕拉丁在发育中的神经系统中的作用，我们检查了缺乏帕拉丁的小鼠胚胎的神经支配，因为在突变型小鼠胚胎大脑中无法检测到 200 kd、140 kd、90-92 kd 和 50 kd 的帕拉丁同工型。与先前研究的结果相反，我们发现缺乏帕拉丁的小鼠胚胎中没有抑制轴突延伸。与野生型小鼠相比，源自缺乏帕拉丁的小鼠的皮质神经元在神经突生长方面也没有明显差异。此外，缺乏帕拉丁的小鼠和野生型小鼠之间衍生自神经干细胞的神经元的神经突生长也没有差异。总之，这些结果表明帕拉丁对于小鼠正常的神经突生长是可有可无的。
