Department of Veterinary Pathobiology

Alexander W.E. Franz
Associate Professor

  • BS: Christian-Albrechts-University, Kiel Germany
  • Ph.D.: Christian-Albrechts-University, Kiel Germany
  • Postdoctoral Fellowships: Plant Research International, Wageningen, Netherlands;Purdue University, IN; Colorado State University, CO

Building Address: 303 Connaway Hall
Phone Number: (573) 884-2635







Research Emphasis: The research work in my laboratory focuses on the molecular interactions of arthropod-borne (arbo)viruses such as dengue, chikungunya, Zika viruses with the yellow fever mosquito, Aedes aegypti. These mosquito-borne viruses are important human pathogens, which have been responsible for recent explosive disease outbreaks throughout the tropical regions of the world.

Our goal is to understand the molecular basis of mosquito vector competence for arboviruses to develop novel strategies aiming at interrupting the viral disease cycle in the insect. One research effort focuses on the mosquito’s innate RNA interference (RNAi) pathway. We investigate how RNAi modulates arbovirus infections and how the RNAi pathway can be manipulated to block arbovirus replication in relevant mosquito tissues. An important tool for this research is the germline transformation of Ae. aegypti.  As a proof-of-principle study for a novel control strategy in the field, we previously generated transgenic Ae. aegypti, which are refractory to dengue 2 virus by tissue-specifically triggering the RNAi pathway against the virus.

Another research project addresses a long-standing question in arbovirology/vector biology: how do arboviruses traverse the tissue (organ) barriers in their insect vectors? Specifically, we are looking at the mechanism(s) underlying the dissemination of arboviruses from the midgut of Ae. aegypti. Observations with chikungunya virus (Togaviridae), and Zika virus (Flaviviridae) indicate that the midgut basal lamina acts as a barrier for the viruses and becomes permissive after bloodmeal ingestion, allowing virions to exit the midgut. Enzymatic activity is likely required to facilitate extracellular matrix rearrangements, which affect the midgut permissiveness for the viruses. Our laboratory has obtained funding from NIH for a five year period to further pursue this exciting research project.

In a continuous effort, we are investigating novel approaches to optimize transgene expression in Ae. aegypti, including the use of site-specific integration technology, novel tissue-specific promoters, and gene-knockdown/knockout strategies. For the first time, we successfully applied the CRISPR/Cas9 system in mosquitoes to stably disrupt the coding sequence of a gene.







Teaching Responsibilities: Course Director for MICROB 4303/7303 "Fundamental Virology"; lecturer in MICROB 9001 "Topics in Microbiology - Advanced Virology"

Selected Publications:

  1. Williams, A.E., Franz, A.W.E., Reid, W.R., Olson, K.E. (2019). Anti-viral effectors and gene drive strategies for mosquito population suppression or replacement to mitigate arbovirus transmission by Aedes aegypti. Insects. [submitted].
  2. Cui, Y., Grant, D.G., Lin J., Yu, X., Franz, A.W.E. (2019). Zika virus dissemination from the midgut of Aedes aegypti is facilitated by bloodmeal-mediated structural modification of the midgut basal lamina. Viruses 11(11), pii: E1056.
  3. Kantor, A.M., Lin, J., Wang, A., Thompson D.C., Franz, A.W.E. (2019). Infection pattern of Mayaro virus in Aedes aegypti (Diptera: Culicidae) and transmission potential of the virus in mixed infections with chikungunya virus. Journal of Medical Entomology 56(3), 832-843.
  4. Kantor, A.M., Grant, D.G., Balaraman, V., White, T.A., Franz, A.W.E. (2018). Ultrastructural analysis of chikungunya virus dissemination from the midgut of the yellow fever mosquito, Aedes aegypti. Viruses 10, 571.
  5. Sheridan, M.A., Balaraman, V., Schust, D.J., Ezashi, T., Roberts, R.M., Franz, A.W.E. (2018). African and Asian strains of Zika virus differ in their ability to infect and lyse primitive human placental trophoblast. PLoS One 13(7):e0200086.
  6. Dong, S., Balaraman, V., Kantor, A.M., Lin J., Grant, D.G., Held, N.L., Franz, A.W.E. (2017). Chikungunya virus dissemination from the midgut of Aedes aegypti is associated with temporal basal lamina degradation during bloodmeal digestion. PLoS Neglected Tropical Diseases 11(9): e0006976.
  7. Dong, S., Behura, K.S., Franz, A.W.E. (2017). The midgut transcriptome of Aedes aegypti fed with saline or protein meals containing chikungunya virus reveals genes potentially involved in viral midgut escape. BMC Genomics 18: 382.
  8. Sheridan, M.A., Yunusov, D., Balaraman, V., Alexenko, A.P., Yabe, S., Verjovski-Almeida, S., Schust, D.J., Franz, A.W., Sadovsky, Y., Ezashi, T., Roberts, R.M. (2017). Vulnerability of primitive human placental trophoblast to Zika virus. Proc Natl Acad Sci U S A. 114(9):E1587-E1596.
  9. Kantor, A.M., Dong, S., Held, N.L., Ishimwe, E., Passarelli, A.L., Clem, R.J., Franz, A.W.E. (2017). Identification and initial characterization of matrix metalloproteinases in the yellow fever mosquito, Aedes aegypti. Insect Molecular Biology 26 (1), 113-126.
  10. Dong, S., Kantor, A.M., Lin, J., Passarelli, A.L., Clem, R.J., Franz, A.W.E. (2016). Infection pattern and transmission potential of chikungunya virus in two New World laboratory-adapted Aedes aegypti strains. Scientific Reports 6: 24729.
  11. Olson, K.E. and Franz, A.W.E. (2016). Genetically Modified Vectors for Control of Arboviruses. In: ‘Nikolaos Vasilakis and Duane Gubler, (eds.), Arboviruses: Molecular Biology, Evolution and Control’, Caister Academic Press, Norwich, U.K., 398 pp.
  12. Franz, A.W.E., Kantor, A.M., Passarelli, A.L., Clem R.J. (2015). Tissue barriers to arbovirus infection in mosquitoes. Viruses 7(7), 3741-3767.
  13. Olson, K.E. and Franz, A.W.E. (2015).  Advances in genetically modified Aedes aegypti to control transmission of dengue viruses. Future Virology 10(5), 609-624. 
  14. Dong, S., Lin, J., Held, N.L., Clem, R.J., Passarelli, A.L., Franz, A.W.E. (2015). Heritable CRISPR/Cas9-mediated genome editing in the yellow fever mosquito, Aedes aegypti. PLoS One 10(3): e0122353.
  15. Franz, A.W.E., Balaraman, V., Fraser, M.J. (2015). Disruption of dengue virus transmission by mosquitoes. Current Opinion in Insect Science 6, 1-9.
  16. Franz, A.W.E., Sanchez-Vargas, I., Raban, R.R., Black, IV, W.C., James, A.A., Olson, K.E. (2014).  Fitness impact and stability of a transgene conferring resistance to dengue-2 virus following introgression into a genetically-diverse Aedes aegypti strain. PLoS Neglected Tropical Diseases 8(5): e2833. 
  17. Franz, A.W.E., Clem, R.J., Passarelli, A.L. (2014). Novel genetic and molecular tools for the investigation and control of dengue virus transmission by mosquitoes. Current Tropical Medicine Reports 1(1), 21-31.   
  18. Steel, J.J., Franz, A.W.E., Sanchez-Vargas, I., Olson, K.E., Geiss, B.J. (2013). Subgenomic reporter RNA system for detection of alphavirus infection in mosquitoes. PLoS One 8(12), e84930.
  19. Khoo, C.C.H., Doty, J.B., Held, N.L., Olson, K.E., Franz, A.W.E. (2013). Isolation of midgut escape mutants of two American genotype dengue 2 viruses from Aedes aegypti. Virology Journal 10(1):257.


©2012 Curators of the University of Missouri - College of Veterinary Medicine



University of Missouri College of Veterinary Medicine University of Missouri