24小时热门版块排行榜

返回列表

biomill8358

无虫 (小有名气)

应助: 0 (幼儿园)
金币: -3
帖子: 58
在线: 6.5小时
虫号: 689651

[资源] 标记的内源性的β-actinmRNA在核质转运过程中的体内成像

In vivo imaging of labelledendogenous β-actinmRNA during nucleocytoplasmictransport
标记的内源性的β-actinmRNA在核质转运过程中的体内成像
David Grünwald & Robert H. Singer
Nature : (2010) DOI: doi:10.1038/nature09438 Received 03 November 2009 Accepted 23 August 2010 Published online 15 September 2010
摘要：Export of messenger RNA occurs via nuclear pores, which are large nanomachineswith diameters of roughly 120 nm that are the only link between the nucleus and cytoplasm1. Hence, mRNA export occurs over distances smaller than the optical resolution of conventional light microscopes. There is extensive knowledge on the physical structure and composition of the nuclear pore complex2, 3, 4, 5, 6, 7, but transport selectivity and the dynamics of mRNA export at nuclear pores remain unknown8. Here we developed a super-registration approach using fluorescence microscopy that can overcome the current limitations of co-localization by means of measuring intermolecular distances of chromatically different fluorescent molecules with nanometreprecision. With this method we achieve 20-ms time-precision and at least 26-nm spatial precision, enabling the capture of highly transient interactions in living cells. Using this approach we were able to spatially resolve the kinetics of mRNA transport in mammalian cells and present a three-step model consisting of docking (80 ms), transport (5–20 ms) and release (80 ms), totalling180 10 ms.Notably, the translocation through the channel was not the rate-limiting step, mRNAs can move bi-directionally in the pore complex and not all pores are equally active.
1.mRNA的输出通过核孔。因此，mRNA输出发生在小于常规光学显微镜分辨率的距离。对于核孔的物理结构化组成有了许多认识，但它的选择性运输和发生在此处的mRNA的动态输出还不了解。
2.我们开发了一个用荧光显微镜超登记的方法。得到了20毫秒，至少26纳米的精确度，能捕捉活细胞中非常短暂的相互作用。
3.用这一方法，能在空间上解决哺乳动物细胞中mRNA的动力学问题，并展示一个3步模型：停靠（80毫秒），转运（5-20毫秒）和释放（80毫秒），共计18010毫秒。
4.特别地，通过隧道的易位并不是限速步骤，mRNA在核孔复合体（NPC）中能双向移动且并不是所有的核孔都是同样的活跃。
更多资料请登录www.bioknow.cn

回复此楼