title: Identification of microsporidia host-exposed proteins reveals a repertoire of rapidly evolving proteins.
abstract: Pathogens use a variety of secreted and surface proteins to interact with and manipulate their hosts, but a systematic approach for identifying such proteins has been lacking. To identify these 'host-exposed' proteins, we used spatially restricted enzymatic tagging followed by mass spectrometry analysis of Caenorhabditis elegans infected with two species of Nematocida microsporidia. We identified 82 microsporidia proteins inside of intestinal cells, including several pathogen proteins in the nucleus. These microsporidia proteins are enriched in targeting signals, are rapidly evolving and belong to large Nematocida-specific gene families. We also find that large, species-specific families are common throughout microsporidia species. Our data suggest that the use of a large number of rapidly evolving species-specific proteins represents a common strategy for microsporidia to interact with their hosts. The unbiased method described here for identifying potential pathogen effectors represents a powerful approach to study a broad range of pathogens.
authors.affiliation: Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, USA.
authors.forename: Aaron W
authors.initials: AW
authors.lastname: Reinke
authors.affiliation: Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, USA.
authors.forename: Keir M
authors.initials: KM
authors.lastname: Balla
authors.affiliation: Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, USA.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Bennett
authors.affiliation: Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, USA.
authors.forename: Emily R
authors.initials: ER
authors.lastname: Troemel
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics / Q000378:metabolism / Q000382:microbiology*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism / Q000382:microbiology; D004847:Epithelial Cells / Q000378:metabolism* / Q000382:microbiology; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D054884:Host-Pathogen Interactions; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000382:microbiology; D016814:Microsporidia / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D015222:Sodium Channels / Q000235:genetics / Q000378:metabolism
chemical_list: D029742:Caenorhabditis elegans Proteins; D005656:Fungal Proteins; D015222:Sodium Channels; C489774:apx-1 protein, C elegans