Journal
JOURNAL OF CELL BIOLOGY
Volume 151, Issue 1, Pages 179-186Publisher
ROCKEFELLER UNIV PRESS
DOI: 10.1083/jcb.151.1.179
Keywords
endocytosis; microtubules; kinesin dynein; motility
Categories
Funding
- NIDDK NIH HHS [DK41918, DK41296] Funding Source: Medline
Ask authors/readers for more resources
Endocytic vesicles undergo fission to sort ligand from receptor. Using quantitative immunofluorescence and video imaging, we provide the first in vitro reconstitution of receptor-ligand sorting in early endocytic vesicles derived from rat liver. We show that to undergo fission, presegregation vesicles must bind to microtubules (MTs) and move upon addition of ATP. Over 13% of motile vesicles elongate and are capable of fission, After fission, one vesicle continues to move, whereas the other remains stationary, resulting in their separation, On average, almost 90% receptor is found in one daughter vesicle! whereas ligand is enriched by similar to 300% with respect to receptor in the other daughter vesicle. Although studies performed on polarity marked MTs showed approximately equal plus and minus end-directed motility, immunofluorescence microscopy revealed that kinesins, but not dynein, were associated with these vesicles. Motility and fission were prevented by addition of 1 mM 5'-adenylylimido-diphosphate (AMP-PNP, an inhibitor of kinesins) or incubation with kinesin antibodies, but were unaffected by addition of 5 mu M vanadate (a dynein inhibitor) or dynein antibodies. These studies indicate an essential role of kinesin-based MT motility in endocytic vesicle sorting, providing a system in which factors required for endocytic vesicle processing can be identified and characterized.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available