Matsuura-Tokita Kumi, Takeuchi Masaki, Ichihara Akira, Mikuriya Kenta, Nakano Akihiko
Molecular Membrane Biology Laboratory, RIKEN Discovery Research Institute, Wako, Saitama 351-0198, Japan.
Nature. 2006 Jun 22;441(7096):1007-10. doi: 10.1038/nature04737. Epub 2006 May 14.
There is a debate over how protein trafficking is performed through the Golgi apparatus. In the secretory pathway, secretory proteins that are synthesized in the endoplasmic reticulum enter the early compartment of the Golgi apparatus called cis cisternae, undergo various modifications and processing, and then leave for the plasma membrane from the late (trans) cisternae. The cargo proteins must traverse the Golgi apparatus in the cis-to-trans direction. Two typical models propose either vesicular transport or cisternal progression and maturation for this process. The vesicular transport model predicts that Golgi cisternae are distinct stable compartments connected by vesicular traffic, whereas the cisternal maturation model predicts that cisternae are transient structures that form de novo, mature from cis to trans, and then dissipate. Technical progress in live-cell imaging has long been awaited to address this problem. Here we show, by the use of high-speed three-dimensional confocal microscopy, that yeast Golgi cisternae do change the distribution of resident membrane proteins from the cis nature to the trans over time, as proposed by the maturation model, in a very dynamic way.
关于蛋白质如何通过高尔基体进行运输存在争议。在分泌途径中，在内质网中合成的分泌蛋白进入高尔基体的早期区室，即顺面扁平囊，经历各种修饰和加工，然后从晚期（反面）扁平囊离开前往质膜。货物蛋白必须沿顺向到逆向的方向穿过高尔基体。两种典型模型分别提出了囊泡运输或扁平囊进展与成熟来解释这一过程。囊泡运输模型预测高尔基体扁平囊是通过囊泡运输连接的不同稳定区室，而扁平囊成熟模型预测扁平囊是从头形成、从顺面到反面成熟然后消散的瞬时结构。长期以来一直期待活细胞成像技术的进步来解决这个问题。在这里，我们通过使用高速三维共聚焦显微镜表明，酵母高尔基体扁平囊确实会随着时间的推移以非常动态的方式改变驻留膜蛋白的分布，从顺面性质转变为反面性质，正如成熟模型所提出的那样。
