Lysosomal Enzyme Trafficking between Phagosomes, Endosomes, and Lysosomes in J774 Macrophages
ENRICHMENT OF CATHEPSIN H IN EARLY ENDOSOMES*
- Volker Claus‡,
- Andrea Jahraus§,
- Torunn Tjelle¶,
- Trond Berg¶,
- Heidrun Kirschke‖,
- Heinz Faulstich‡ and
- Gareth Griffiths§
- From the ‡Max Planck Institute for Medical Research, Heidelberg, §EMBL, 69117 Heidelberg, Germany,¶Department of Biology, University of Oslo, Oslo, 0316 Norway, and ‖Department of Biochemistry, University of Halle, D-06097 Halle, Germany
Abstract
In this study we take advantage of recently developed methods using J774 macrophages to prepare enriched fractions of early endosomes, late endosomes, dense lysosomes, as well as phagosomes of different ages enclosing 1-μm latex beads to investigate the steady state distribution and trafficking of lysosomal enzyme activity between these organelles. At steady state these cells appear to possess four different cellular structures, in addition to phagolysosomes, where acid hydrolases were concentrated. The first site of hydrolase concentration was the early endosomes, which contained the bulk of the cellular cathepsin H. This enzyme was acquired by phagosomes significantly faster than the other hydrolases tested. The second distinct site of lysosomal enzyme concentration was the late endosomes which contain the bulk of cathepsin S. The third and fourth large pools of hydrolases were found in two functionally distinct types of dense lysosomes, only one of which was found to be secreted in the presence of chloroquine or bafilomycin. Among this secreted pool was soluble furin, generally considered only as a membrane-bound trans-Golgi network resident protein. Thus, the organelles usually referred to as “lysosomes” in fact encompass a growing family of highly dynamic but functionally distinct endocytic organelles.
Footnotes
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↵* This work was supported by SFB352 of the Deutsche Forschungs Gemeinschaft and by a grant from the Human Frontier Network (to G. G.).The costs of publication of this article were defrayed in part by the payment of page charges. The article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
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↵1 A. Jahraus, T. E. Tjelle, A. Habermann, B. Storrie, O. Ullrich, and G. Griffiths, submitted for publication.
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↵2 The abbreviations used are: HRP, horseradish peroxidase; BSA, bovine serum albumin; PBS, phosphate-buffered saline; Z, benzyloxycarbonyl; AMC, 7-amino-4-methylcoumarin; PNS, postnuclear supernatant.
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↵3 V. Claus, A. Jahraus, T. Tjelle, T. Berg, H. Kirschke, H. Faulstich, and G. Griffiths, unpublished observations.
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↵4 J. Heuser, personal communication.
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- Received July 8, 1997.
- Revision received February 2, 1998.
- The American Society for Biochemistry and Molecular Biology, Inc.
