关键看细节!细胞内物质如何“高速运输”被曝光
2017/11/14
除了构成细胞骨架,微管还是胞内“高速公路”的基本组成,负责物质运输。最新一篇在线发表在《Current Biology》期刊上的文章,揭示了细胞协调关键酶实现“交通管制”的具体细节,为脊髓损伤、神经衰退性疾病的治疗提供了新的线索。


Robert O'Haga

细胞是生物体基本的结构和功能单位,为了确保生存和功能发挥,它需要在正确的时间将正确数量的物质运输至正确的位置。

这一过程中,细胞是如何利用酶有条不紊地实现“交通管制”的呢?来自于罗格斯大学新布朗斯维克校区的研究团队最新发现,这与胞内的高速公路——微管以及两种“发动机”——驱动蛋白(kinesins)和动力蛋白(dyneins)有关(负责驱动“货物”在公路上的运输速度)。

细胞内的高速运输系统如何运行和维持?文章作者、人类遗传研究所、罗格斯大学新布伦瑞克大学遗传学系助理教授Robert O'Haga带领团队以一种微型蛔虫(C. elegans)为模型,深入研究纤毛内微管执行感官任务的细节。他们发现,细胞内存在一种酶TTLL-11负责促进由谷氨酸组成的“交通信号”,从而调控蛋白运输的速度。另一种酶CCPP-1则负责抑制谷氨酸活性,防止它们累积过多。


细胞内物质运输的细节(图片来源: Nick Romanenko/Rutgers University)

这两种作用相反的酶协同合作,确保运动蛋白正确调控细胞内的运输。此外,他们还发现,谷氨酸也负责“道路维修”——改变微管的结构。

有意思的是,在衰老细胞中,这些酶对于视觉以及神经元而言至关重要。这意味着,靶向这些酶有望治疗神经衰退性疾病或者神经损伤。下一步,研究团队将以小鼠等动物作为模型,进一步挖掘相关机制。


遗传学教授Maureen m . Barr(左)、助理研究员Robert O' hagan(中)和实验室技术员Yasmin Ramadan(右)(图片来源:Nick Romanenko/Rutgers University)

参考资料:

How to control traffic on cellular highways

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