Our research generally focuses on understanding how microorganisms and their hosts interact at different biological levels (e.g. molecular, cellular, genetic, ecological and evolutionary). Specifically, we are interested in the interactions of the intracellular bacteria Wolbachia with their host cells. The infection of invertebrates by Wolbachia represents one of the great pandemics on this planet. Even though Wolbachia is one of the most abundant intracellular bacteria on earth, infecting up to 70% of arthropods and filarial nematodes, their mechanisms of transmission are poorly understood.
Beyond fundamental questions of host-microbe interactions, understanding Wolbachia biology also has specific medical relevance. (i) Closely related Rickettsial bacteria cause many vector-borne emerging human diseases, such as diverse forms of typhus and spotted fever . (ii) Wolbachia provides new approaches to treat human and animal filariasis - devastating diseases including river blindness and elephantiasis - caused by parasitic worms. (iii) Wolbachia is a potential agent to control insect vectors that transmit diseases such as dengue, filariasis and malaria.
The broad aim of my laboratory is to identify the mechanisms required for maintenance of Wolbachia infection through successive generations of their host (vertical transmission) and for infection into new hosts (horizontal or infectious transmission). Our work demonstrates that Wolbachia preferentially populate the stem cell niche, the region of the fly ovary containing the stem cells. Tropism for the stem cell niche provides a previously undetected route to reach the germ line. The targeting of stem cell niche by Wolbachia may facilitate their horizontal and vertical transmission.
Toomey ME, Frydman HM. Extreme divergence of Wolbachia tropism for the stem-cell-niche in the Drosophila testis.
[PLOS Pathogens - 2014]
Toomey ME, Panaram K, Fast EM, Beatty C, Frydman HM. Evolutionarily conserved Wolbachia-encoded factors control pattern of stem-cell niche tropism in Drosophila ovaries and favor infection.
[PNAS - 2013]
Fast E, Toomey ME, Panaram K, Desjardins D, Kolaczyk E, Frydman HM. Wolbachia enhance Drosophila stem cell proliferation and target the germline stem cell niche.
[Science - 2011]
Frydman HM. Wolbachia Bacterial Infection in Drosophila.
[JOVE - 2007]
Beaucher M, Goodliffe J, Hersperger E, Trunova S, Frydman HM, Shearn A. Drosophila brain tumor metastases express both neuronal and glial cell type markers.
[Developmental Biology - 2007]
Frydman HM, Li JM, Robson D, Wieschaus E. Somatic stem cell niche tropism in Wolbachia.
[Nature - 2006]
Frydman HM. Isolation of live bacteria from adult insects.
[Nature Protocols - 2006]
Ferre PM, Frydman HM, Li JM, Cao J, Wieschaus E, Sullivan W. Wolbachia utilizes host microtubules and Dynein for anterior localization in the Drosophila oocyte.
[PLOS Pathogens - 2005]
Frydman HM, Spradling AC. The receptor-like tyrosine phosphatase lar is required for epithelial planar polarity and for axis determination within drosophila ovarian follicles.
[Development - 2001]
Rama Krishna Simhadri's poster highlighted at the Animal-Microbe Symbioses
Gordon Research Conference!
Michelle Toomey & Rama Krishna Simhadri win student awards for best talks at the 8th International Wolbachia Conference!
Toomey et al. 2013 PNAS paper featured in Science Daily!
Eva Fast awarded the Austrian Scientists & Scholars In Northern America Award (ASCINA) by the Austrian Minister of Science & Research!