Abstract

A fluorescence assay was developed to measure the rate of fusion of highly purified clathrin-coated vesicles isolated from bovine brain with purified lysosomes isolated from bovine kidney. Coated vesicles and stripped vesicles, prepared by removal of clathrin from coated vesicles with dilute alkaline buffer, were labeled with the nonfluorescent dye 6-carboxydiacetylfluorescein. Fusion of the vesicles with lysosomes resulted in mixing of the vesicle contents and exposure of 6-carboxydiacetylfluorescein to lysosomal esterases, which hydrolyze the probe's acetate groups to give the fluorescent 6-carboxyfluorescein. Fusion was therefore measured by recording the increase in fluorescence obtained upon mixing the vesicles with lysosomes. The results of the experiments indicated that the clathrin coat of coated vesicles inhibited the fusion of the vesicle membrane with that of the lysosome. In addition, fusion appears to require free Ca 2+ and does not require vesicle-surface protein.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.