A phorbol ester-binding protein is required downstream of Rab5 in endosome fusion.

Published

Journal Article

Previous observations indicate that a zinc and phorbol ester binding factor is necessary for endosome fusion. To further characterize the role of this factor in the process, we used an in vitro endosome fusion assay supplemented with recombinant Rab5 proteins. Both zinc depletion and addition of calphostin C, an inhibitor of protein kinase C, inhibited endosome fusion in the presence of active Rab5. Addition of the phorbol ester PMA (phorbol 12-myristate 13-acetate) reversed the inhibition of endosome fusion caused by a Rab5 negative mutant. Moreover, PMA stimulated fusion in the presence of Rab5 immunodepleted cytosol. These results suggest that the phorbol ester binding protein is acting downstream of Rab5 in endosome fusion.

Full Text

Cited Authors

  • Aballay, A; Barbieri, MA; Colombo, MI; Arenas, GN; Stahl, PD; Mayorga, LS

Published Date

  • December 1998

Published In

Volume / Issue

  • 441 / 3

Start / End Page

  • 373 - 378

PubMed ID

  • 9891974

Pubmed Central ID

  • 9891974

Electronic International Standard Serial Number (EISSN)

  • 1873-3468

International Standard Serial Number (ISSN)

  • 0014-5793

Digital Object Identifier (DOI)

  • 10.1016/s0014-5793(98)01579-8

Language

  • eng