Jason Mercer Research Group

2005 Ph.D. Microbiology and Molecular Genetics; Medical College of Wisconsin, USA
1998 B.A. Biological Sciences; Northern Illinois University, USA
Jason Mercer
Tel: +44 (0) 20 7679 3528
Fax: +44 (0) 20 7679 7805
2015-2020 ERC Consolidator Grant
2011-2014 Swiss National Science Foundation Ambizione
2008-2010 EMBO Long-term Postdoctoral Fellowship
2007-2008 Roche Postdoctoral Fellowship
1997 NIU at Oxford Research Fellowship
Previous Posts: 
2011-2014 Oberassistent/Group Leader; ETH Zurich, Switzerland
2006-2011 Postdoctoral Fellow; ETH Zurich, Switzerland

Cell Biology of Virus Infection


obligate intracellular parasites viruses intimately rely on host cell factors
for all stages of their replication.  Our
group is interested in deciphering the complex interactions that occur between poxviruses
and their host cells during all stages of the infection cycle. We investigate how
viruses initiate their internalization by endocytosis, and how they utilize transport
within cellular endocytic systems to their advantage.  We are also analyzing how the viral genome and
accessory proteins escape into the cytosol, and how replication proceeds.

these we combine cellular, molecular, and virological techniques with state-of-the-art
technologies such as automated small compound and image-based siRNA screening, advanced
proteomics, live cell microscopy, and electron microscopy. Our particular
interests lie in uncovering novel mechanisms by which viruses subjugate host
cell functions to facilitate their entry, replication, and spread.

VACV Assays

Systematic analysis of the poxvirus lifecycle. Representative images of each of the stages of the
virus lifecycle for which we have developed specific, quantitative, high- or medium-
throughput assays.


CR Cover

Cell Reports on the cover: Vaccinia virus, the prototypic poxvirus, is complex in structure. Virions consist of a lipid bilayer surrounding a genome-containing core, which is flanked by two proteinaceous lateral bodies, the composition and function of which has remained enigmatic for over 40 years. In this issue, Mercer and colleagues show that poxvirus lateral bodies, akin to herpesvirus tegument, serve as delivery containers for viral immunomodulatory proteins. The cover image shows a collection of immunoelectron micrographs of vaccinia virions labeled for the viral protein F17, identified as a major lateral body component. Images by C.K.E. Bleck.




Highlighted publication = Selected Publication

  • 2015
  • Bidgood, S. R., & Mercer, J. (2015). Cloak and dagger: Alternative immune evasion and modulation strategies of poxviruses. Viruses, 7 (8), 4800-4825. doi:10.3390/v7082844
  • Kilcher, S., & Mercer, J. (2015). DNA virus uncoating. Virology, 479-480, 578-590. doi:10.1016/j.virol.2015.01.024
  • Highlighted publication
    Rizopoulos, Z., Balistreri, G., Kilcher, S., Martin, C. K., Syedbasha, M., Helenius, A., & Mercer, J. (2015). Vaccinia Virus Infection Requires Maturation of Macropinosomes. Traffic, 16 (8), 814-831. doi:10.1111/tra.12290
  • Amara, A., & Mercer, J. (2015). Viral apoptotic mimicry. Nature Reviews Microbiology, 13 (8), 461-469. doi:10.1038/nrmicro3469
  • 2014
  • Kilcher, S., & Mercer, J. (2014). DNA virus uncoating. Virology. doi:10.1016/j.virol.2015.01.024
  • Mazzon, M., & Mercer, J. (2014). Lipid interactions during virus entry and infection. Cell Microbiol, 16 (10), 1493-1502. doi:10.1111/cmi.12340
  • Kilcher, S., & Mercer, J. (2014). Next generation approaches to study virus entry and infection. Current Opinion in Virology, 4, 8-14. doi:10.1016/j.coviro.2013.10.002
  • Rämö, P., Drewek, A., Arrieumerlou, C., Beerenwinkel, N., Ben-Tekaya, H., Cardel, B., . . . Dehio, C. (2014). Simultaneous analysis of large-scale RNAi screens for pathogen entry. BMC Genomics, 1-18. doi:10.1186/1471-2164-15-1162
  • Highlighted publication
    Kilcher, S., Schmidt, F. I., Schneider, C., Kopf, M., Helenius, A., & Mercer, J. (2014). siRNA Screen of Early Poxvirus Genes Identifies the AAA+ ATPase D5 as the Virus Genome-Uncoating Factor. Cell Host & Microbe, 15 (1), 103-112. doi:10.1016/j.chom.2013.12.008
  • 2013
  • Unger, B., Mercer, J., Boyle, K. A., & Traktman, P. (2013). Biogenesis of the Vaccinia Virus Membrane: Genetic and Ultrastructural Analysis of the Contributions of the A14 and A17 Proteins. Journal of Virology, 87 (2), 1083-1097. doi:10.1128/JVI.02529-12
  • Mercer, J., & Lozach, P. -. Y. (2013). Cellular protein disposal system assists poxvirus genome uncoating. Medecine/Sciences, 29 (6-7), 561-563. doi:10.1051/medsci/2013296002
  • Schmidt, F. I., Kuhn, P., Robinson, T., Mercer, J., & Dittrich, P. S. (2013). Single-Virus Fusion Experiments Reveal Proton Influx into Vaccinia Virions and Hemifusion Lag Times. Biophysical Journal, 105 (2), 420-431. doi:10.1016/j.bpj.2013.06.016
  • Wang, I. -. H., Suomalainen, M., Andriasyan, V., Kilcher, S., Mercer, J., Neef, A., . . . Greber, U. F. (2013). Tracking viral genomes in host cells at single-molecule resolution. Cell Host and Microbe, 14 (4), 468-480. doi:10.1016/j.chom.2013.09.004
  • Schmidt, F. I., Bleck, C. K. E., Reh, L., Novy, K., Wollscheid, B., Helenius, A., . . . Mercer, J. (2013). Vaccinia Virus Entry Is Followed by Core Activation and Proteasome-Mediated Release of the Immunomodulatory Effector VH1 from Lateral Bodies. Cell Reports, 4 (3), 464-476. doi:10.1016/j.celrep.2013.06.028
  • Nicola, A. V., Aguilar, H. C., Mercer, J., Ryckman, B., & Wiethoff, C. M. (2013). Virus entry by endocytosis. Advances in Virology, 2013. doi:10.1155/2013/469538
  • Mercer, J., & Greber, U. F. (2013). Virus interactions with endocytic pathways in macrophages and dendritic cells. Trends Microbiol, 21 (8), 380-388. doi:10.1016/j.tim.2013.06.001
  • 2012
  • Kuhn, P., Eyer, K., Robinson, T., Schmidt, F. I., Mercer, J., & Dittrich, P. S. (2012). A facile protocol for the immobilisation of vesicles, virus particles, bacteria, and yeast cells. Integr Biol (Camb), 4 (12), 1550-1555. doi:10.1039/c2ib20181j
  • Stiefel, P., Schmidt, F. I., Dörig, P., Behr, P., Zambelli, T., Vorholt, J. A., & Mercer, J. (2012). Cooperative vaccinia infection demonstrated at the single-cell level using FluidFM. Nano Lett, 12 (8), 4219-4227. doi:10.1021/nl3018109
  • Frei, A. P., Jeon, O. -. Y., Kilcher, S., Moest, H., Henning, L. M., Jost, C., . . . Wollscheid, B. (2012). Direct identification of ligand-receptor interactions on living cells and tissues. NATURE BIOTECHNOLOGY, 30 (10), 997-+. doi:10.1038/nbt.2354
  • Kuhn, P., Schmidt, F. I., Mercer, J., & Dittrich, P. S. (2012). Fusion of vaccinia virus particles with single cells - A kinetic study facilitated by microfluidic technology. Proceedings of the 16th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2012, 16-18.
  • Mercer, J., & Helenius, A. (2012). Gulping rather than sipping: macropinocytosis as a way of virus entry. Curr Opin Microbiol, 15 (4), 490-499. doi:10.1016/j.mib.2012.05.016
  • Schmidt, F. I., Bleck, C. K., & Mercer, J. (2012). Poxvirus host cell entry. Curr Opin Virol, 2 (1), 20-27. doi:10.1016/j.coviro.2011.11.007
  • Mercer, J., Snijder, B., Sacher, R., Burkard, C., Bleck, C. K. E., Stahlberg, H., . . . Helenius, A. (2012). RNAi Screening Reveals Proteasome- and Cullin3-Dependent Stages in Vaccinia Virus Infection. Cell Reports, 2 (4), 1036-1047. doi:10.1016/j.celrep.2012.09.003
  • Snijder, B., Sacher, R., Rämö, P., Liberali, P., Mench, K., Wolfrum, N., . . . Pelkmans, L. (2012). Single-cell analysis of population context advances RNAi screening at multiple levels. Molecular Systems Biology, 8. doi:10.1038/msb.2012.9
  • Schmidt, F. I., & Mercer, J. (2012). Vaccinia virus egress: actin OUT with clathrin. Cell Host Microbe, 12 (3), 263-265. doi:10.1016/j.chom.2012.08.007
  • 2011
  • Schmidt, F. I., Bleck, C. K. E., Helenius, A., & Mercer, J. (2011). Vaccinia extracellular virions enter cells by macropinocytosis and acid-activated membrane rupture. The EMBO Journal, 30 (17), 3647-3661. doi:10.1038/emboj.2011.245
  • Mercer, J. (2011). Viral apoptotic mimicry party: P.S. Bring your own Gas6. Cell Host Microbe, 9 (4), 255-257. doi:10.1016/j.chom.2011.04.002
  • 2010
  • Mercer, J., & Helenius, A. (2010). Apoptotic mimicry: phosphatidylserine-mediated macropinocytosis of vaccinia virus. Ann N Y Acad Sci, 1209, 49-55. doi:10.1111/j.1749-6632.2010.05772.x
  • Mercer, J., Knebel, S., Schmidt, F. I., Crouse, J., Burkard, C., & Helenius, A. (2010). Vaccinia virus strains use distinct forms of macropinocytosis for host-cell entry. Proceedings of the National Academy of Sciences, 107 (20), 9346-9351. doi:10.1073/pnas.1004618107
  • Mercer, J., Schelhaas, M., & Helenius, A. (2010). Virus entry by endocytosis. Annu Rev Biochem, 79, 803-833. doi:10.1146/annurev-biochem-060208-104626
  • 2009
  • Mercer, J., & Helenius, A. (2009). High-throughput siRNA silencing screens to identify host-cell factors required for virus infection. Future Virology, 4 (6), 517-519. doi:10.2217/fvl.09.58
  • Mercer, J., & Helenius, A. (2009). Virus entry by macropinocytosis. Nat Cell Biol, 11 (5), 510-520. doi:10.1038/ncb0509-510
  • 2008
  • Amstutz, B., Gastaldelli, M., Kälin, S., Imelli, N., Boucke, K., Wandeler, E., . . . Greber, U. F. (2008). Subversion of CtBP1-controlled macropinocytosis by human adenovirus serotype 3. EMBO J, 27 (7), 956-969. doi:10.1038/emboj.2008.38
  • Highlighted publication
    Mercer, J., & Helenius, A. (2008). Vaccinia Virus Uses Macropinocytosis and Apoptotic Mimicry to Enter Host Cells. Science, 320 (5875), 531-535. doi:10.1126/science.1155164
  • 2005
  • Mercer, J., & Traktman, P. (2005). Genetic and cell biological characterization of the vaccinia virus A30 and G7 phosphoproteins. Journal of Virology, 79 (11), 7146-7161. doi:10.1128/JVI.79.11.7146-7161.2005
  • 2003
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