Glycosylated α-dystroglycan (α-DG) serves as cellular entry receptor for multiple pathogens, and defects in its glycosylation cause hereditary Walker-Warburg syndrome (WWS). At least eight proteins are critical to glycosylate α-DG, but many genes mutated in WWS remain unknown. To identify modifiers of α-DG, we performed a haploid screen for Lassa virus entry, a hemorrhagic fever virus causing thousands of deaths annually that hijacks glycosylated α-DG to enter cells. In complementary screens, we profiled cells for absence of α-DG carbohydrate chains or biochemically related glycans. This revealed virus host factors and a suite of glycosylation units, including all known Walker-Warburg genes and five additional factors critical for the modification of α-DG. Our findings accentuate the complexity of this posttranslational feature and point out genes defective in dystroglycanopathies.

doi.org/10.1126/science.1233675, hdl.handle.net/1765/40191
Science
Erasmus MC: University Medical Center Rotterdam

Jae, L., Raaben, M., Riemersma, M., van Beusekom, E., Blomen, V., Velds, A., Kerkhoven, R., Carette, J., Topaloglu, H., Meinecke, P., Wessels, M., Lefeber, D., Whelan, S., van Bokhoven, H.& Brummelkamp, T. (2013). Deciphering the glycosylome of dystroglycanopathies using haploid screens for Lassa virus entry. Science, 340(6131), 479–483.https://doi.org/10.1126/science.1233675