1. Spatiotemporal dissection of the trans-Golgi network in budding yeast
- Author
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Tojima, Takuro, Suda, Yasuyuki, Ishii, Midori, Kurokawa, Kazuo, and Nakano, Akihiko
- Subjects
carbohydrates (lipids) ,Trans-Golgi network ,Super-resolution live imaging ,Saccharomyces cerevisiae ,Cisternal maturation ,Membrane traffic ,Research Article - Abstract
The trans-Golgi network (TGN) acts as a sorting hub for membrane traffic. It receives newly synthesized and recycled proteins, and sorts and delivers them to specific targets such as the plasma membrane, endosomes and lysosomes/vacuoles. Accumulating evidence suggests that the TGN is generated from the trans-most cisterna of the Golgi by maturation, but the detailed transition processes remain obscure. Here, we examine spatiotemporal assembly dynamics of various Golgi/TGN-resident proteins in budding yeast by high-speed and high-resolution spinning-disk confocal microscopy. The Golgi–TGN transition gradually proceeds via at least three successive stages: the ‘Golgi stage’ where glycosylation occurs; the ‘early TGN stage’, which receives retrograde traffic; and the ‘late TGN stage’, where transport carriers are produced. During the stage transition periods, earlier and later markers are often compartmentalized within a cisterna. Furthermore, for the late TGN stage, various types of coat/adaptor proteins exhibit distinct assembly patterns. Taken together, our findings characterize the identity of the TGN as a membrane compartment that is structurally and functionally distinguishable from the Golgi. This article has an associated First Person interview with the first author of the paper., Highlighted Article: The TGN displays two sub-stages of maturation: ‘early TGN’, when retrograde traffic is received, and ‘late TGN’, when transport carriers are produced. At the late TGN, various coat/adaptor proteins exhibit distinct assembly dynamics.
- Published
- 2019