田邊　賢司    Department   Research Institutes and Facilities, Research Institutes and Facilities    Position   Associate Professor
Article types	Original article
Language	English
Peer review	Peer reviewed
Title	Fission of tubular endosomes triggers endosomal acidification and movement.
Journal	Formal name：PLoS ONE
Volume, Issue, Page	6,pp.e19764
Author and coauthor	Mesaki, Kumi Tanabe, Kenji Obayashi, Masanori Oe, Natsuko Takei, Kohji
Authorship	Lead author,Corresponding author
Publication date	2011
Summary	The early endosome acts as a sorting station for internalized molecules destined for recycling or degradation. While recycled molecules are sorted and delivered to tubular endosomes, residual compartments containing molecules to be degraded undergo"maturation"before final degradation in the lysosome. This maturation involves acidification, microtubule-dependent motility, and perinuclear localization. It is currently unknown how sorting and the processes of maturation cooperate with each other. Here, we show that fission of a tubular endosome triggers the maturation of the residual endosome, leading to degradation. Use of the dynamin inhibitor dynasore to block tubular endosome fission inhibited acidification, endosomal motility along microtubules, perinuclear localization, and degradation. However, tubular endosome fission was not affected by inhibiting endosomal acidification or by depolymerizing the microtubules. These results demonstrate that the fission of recycling tubules is the first important step in endosomal maturation and degradation in the lysosome. We believe this to be the first evidence of a cascade from sorting to degradation.