Authors

U Dobramysl³; E Ferreira⁴; RP Neish¹; LD Davidson⁸; R Pereira²; R Etzensperger²; S Aellig²; M Young⁵; J Smith⁵; J Damasceno⁷; JD Sunter⁶; J Mottram¹; E Gluenz²; R Wheeler⁹;  ¹ University of York, UK;  ² Institute of Cell Biology, University of Bern, Switzerland;  ³ University of Oxford, UK;  ⁴ University of York, Centre for Immunology and Infection, UK;  ⁵ Institute of Infection, Immunity and Inflammation, University of Glasgow, UK;  ⁶ Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, UK;  ⁷ Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, UK;  ⁸ Oxford Brookes University, UK;  ⁹ Peter Medawar Building for Pathogen Research, Nuffield Department of Medicine, University of Oxford, UK

Discussion

The success of Leishmania parasites as pathogens is encoded in their genome. However, as eukaryotes, their genome is large and relatively complex. Despite extensive efforts for the functional characterisation of protein-coding genes in Leishmania, the role and localisation of most is still unclear. Indeed, according to TriTrypDB only 14% of the 8,267 L. mexicana protein-coding genes have been unambiguously named, with the large majority remaining of putative function or hypothetical. The major aims of the Leishmania Genetic Modification (LeishGEM) project are to systematically address this by:
1)     Determining the fitness of deletion mutants of protein-coding genes (genome-wide, 8,267 genes) by generating uniquely genetically barcoded deletion cell lines and assessing growth fitness as promastigotes, axenic amastigotes, amastigotes in macrophages, and in a mouse footpad infection.
2)     Visualising the sub-cellular localisation proteins in promastigotes and axenic amastigotes by tagging at both the N and C termini (if lacking an ortholog in or divergent from T. brucei, 2,700 target genes) in the LeishTag sub-project.
3)     Analysing the subcellular localisation via LOPIT-DC fractionation.

We are now making the fitness phenotyping and localisation data generated by the LeishGEM project so far available at http://leishgem.org/. As of now, this database contains fitness data for 2,305 gene deletion mutants, subcellular localisation for 1,209 tagged cell lines where we have completed localisation annotation, and 3,782 proteins for which LOPIT-DC fractionation and mass spectroscopy yielded information on the subcellular localisation. This is the first data release of a transformative resource for the function of thousands of genes in a family of important human pathogens.