Format

Send to

Choose Destination
Mol Cell Proteomics. 2015 Jul;14(7):1911-26. doi: 10.1074/mcp.M114.047647. Epub 2015 Apr 30.

Architecture of a Host-Parasite Interface: Complex Targeting Mechanisms Revealed Through Proteomics.

Author information

1
From the ‡School of Life Sciences, University of Nottingham, Nottingham, UK, NG2 7UH; §Department of Pathology, University of Cambridge, Cambridge, UK, CB2 1QP; catarina.gadelha@nottingham.ac.uk.
2
¶Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, 10021;
3
From the ‡School of Life Sciences, University of Nottingham, Nottingham, UK, NG2 7UH;
4
‖Division of Biological Chemistry and Drug Discovery, University of Dundee, Dundee, UK, DD1 5EH.

Abstract

Surface membrane organization and composition is key to cellular function, and membrane proteins serve many essential roles in endocytosis, secretion, and cell recognition. The surface of parasitic organisms, however, is a double-edged sword; this is the primary interface between parasites and their hosts, and those crucial cellular processes must be carried out while avoiding elimination by the host immune defenses. For extracellular African trypanosomes, the surface is partitioned such that all endo- and exocytosis is directed through a specific membrane region, the flagellar pocket, in which it is thought the majority of invariant surface proteins reside. However, very few of these proteins have been identified, severely limiting functional studies, and hampering the development of potential treatments. Here we used an integrated biochemical, proteomic and bioinformatic strategy to identify surface components of the human parasite Trypanosoma brucei. This surface proteome contains previously known flagellar pocket proteins as well as multiple novel components, and is significantly enriched in proteins that are essential for parasite survival. Molecules with receptor-like properties are almost exclusively parasite-specific, whereas transporter-like proteins are conserved in model organisms. Validation shows that the majority of surface proteome constituents are bona fide surface-associated proteins and, as expected, most present at the flagellar pocket. Moreover, the largest systematic analysis of trypanosome surface molecules to date provides evidence that the cell surface is compartmentalized into three distinct domains with free diffusion of molecules in each, but selective, asymmetric traffic between. This work provides a paradigm for the compartmentalization of a cell surface and a resource for its analysis.

PMID:
25931509
PMCID:
PMC4587319
DOI:
10.1074/mcp.M114.047647
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center