Lauren Varanese

All Publications

• MFSD6 is an entry receptor for enterovirus D68. Nature Varanese, L., Xu, L., Peters, C. E., Pintilie, G., Roberts, D. S., Raj, S., Liu, M., Ooi, Y. S., Diep, J., Qiao, W., Richards, C. M., Callaway, J., Bertozzi, C. R., Jabs, S., de Vries, E., van Kuppeveld, F. J., Nagamine, C. M., Chiu, W., Carette, J. E. 2025

  Abstract

  With the near eradication of poliovirus due to global vaccination campaigns, attention has shifted to other enteroviruses that can cause polio-like paralysis syndrome (now termed acute flaccid myelitis (AFM))1-3. In particular, enterovirus D68 (EV-D68) is believed to be the main driver of epidemic outbreaks of AFM in recent years4, yet not much is known about EV-D68 host interactions. EV-D68 is a respiratory virus5 but, in rare cases, can spread to the central nervous system to cause severe neuropathogenesis. Here, we used genome-scale CRISPR screens to identify the poorly characterized multipass membrane transporter MFSD6 as a host entry factor for EV-D68. Knockout of MFSD6 expression abrogated EV-D68 infection in cell lines and primary cells corresponding to respiratory and neural cells. MFSD6 localized to the plasma membrane and was required for viral entry into host cells. MFSD6 bound directly to EV-D68 particles via its third extracellular loop (L3). We determined the cryo-EM structure of EV-D68 in complex with L3 at 2.1 A resolution, revealing the interaction interface. A decoy receptor, engineered by fusing MFSD6(L3) to Fc, blocked EV-D68 infection of human primary lung epithelial cells, and provided near complete protection in a lethal mouse model of EV-D68 infection. Collectively, our results reveal MFSD6 as an entry receptor for EV-D68, and support targeting MFSD6 as a potential mechanism to combat infections by this emerging pathogen with pandemic potential.

  View details for DOI 10.1038/s41586-025-08908-0

  View details for PubMedID 40132641

• The human disease gene LYSET is essential for lysosomal enzyme transport and viral infection. Science (New York, N.Y.) Richards, C. M., Jabs, S., Qiao, W., Varanese, L. D., Schweizer, M., Mosen, P. R., Riley, N. M., Klüssendorf, M., Zengel, J. R., Flynn, R. A., Rustagi, A., Widen, J. C., Peters, C. E., Ooi, Y. S., Xie, X., Shi, P. Y., Bartenschlager, R., Puschnik, A. S., Bogyo, M., Bertozzi, C. R., Blish, C. A., Winter, D., Nagamine, C. M., Braulke, T., Carette, J. E. 2022: eabn5648

  Abstract

  Lysosomes are key degradative compartments of the cell. Transport to lysosomes relies on GlcNAc-1-phosphotransferase-mediated tagging of soluble enzymes with mannose 6-phosphate (M6P). GlcNAc-1-phosphotransferase deficiency leads to the severe lysosomal storage disorder mucolipidosis II (MLII). Several viruses require lysosomal cathepsins to cleave structural proteins and thus depend on functional GlcNAc-1-phosphotransferase. Here, we used genome-scale CRISPR screens to identify Lysosomal Enzyme Trafficking factor (LYSET) as essential for infection by cathepsin-dependent viruses including SARS-CoV-2. LYSET deficiency resulted in global loss of M6P tagging and mislocalization of GlcNAc-1-phosphotransferase from the Golgi complex to lysosomes. Lyset knockout mice exhibited MLII-like phenotypes and human pathogenic LYSET alleles failed to restore lysosomal sorting defects. Thus, LYSET is required for correct functioning of the M6P trafficking machinery, and mutations in LYSET can explain the phenotype of the associated disorder.

  View details for DOI 10.1126/science.abn5648

  View details for PubMedID 36074821