Wolbachia Google imagesTEM; Google images

Concepts Endosymbioses Host manipulation Co-evolution Google images

History One of the most infectious bacterial genera on earth Endosymbionts First discovered in 1924 in insects; largely unknown until the 1990s (Evade detection) Now known to be in nematodes Applications for bio-control and treatment of nematode diseases

Diversity Infects over 1 million species of insects and other invertebrates! Google images

Stevens et al, 2001

Wolbachia in insects Maternally inherited (Usually) Cytoplasmic incompatibility Induced parthogenesis, functional feminization, and male killing Protection from parasitoid wasp in pea aphids Evolutionary implications

Cytoplasmic Incompatibility (CI) Cytoplasmic incompatibility Tortora et al, 2010

Biocontrol (economic implications) Cytoplasmic incompatibility has enormous implications for bio-control Exp 1) The Med fly- experimentally inoculated males induced complete (CI) in target populations Populations were “suppressed” by a single release of infected males Zabalou et al, 2004

Evolutionary Implications Experiment 2- Antibiotic treatment in wasps Does Walbachia help maintain the uniqueness of it’s hosts species by impeding “hybrid” development? How has Wolbachia influenced the evolution of insects? Google images Hybridization!

A twist: Wolbachia is found in filarial nematodes where it is discovered to be an vital symbiont Google images

Co-evolution Strong evidence for co-evolution between endosymbiont Wolbachia and nematodes Phylogenetic congruency Long history of vertical transmission

An Obligate Endosymbiosis Wolbachia vital for embryogenesis in adult females Inhibition of microfilariae Molt inhibition

Filariasis in Humans and animals 200 million individuals infected across 90 countries (krager, 2007 as cited by Hoerauf ) Canine Heart Worm D. immitis Elephantiasis /ESLF Wuchereria bancrofti River Blindess O. ochengi

Traditional Treatment (Filariasis) Traditional treatment for lymphatic Filariasis - Ivermectin Now- Effectively use chemotherapy to disrupt parasite/symbiont interactions in filarial nematodes

Medical Application? Experiment 3 A doxycyline regime can be used to treat (Ghanaian) individuals for lymphatic filariasis by targeting the host symbiont Results: a 99% reduction in microfilaria Implications- doxycyline as a universal treatment for filariasis in humans

Ivermectin vs Doxycycline $ USD/ 3 mg (Merck) Neurotoxic effects Annual Treatment -Kills the microfilariae not the worm $ USD/100mg Pregnancy risk factor D 6 weeks course, makes adult worms sterile VS Google images

Conclusions Wolbachia is a fundamental bacteria genus Further study of this endosymbiont will enhance our understanding of evolutionary entomology, Nematode symbiont coeveolution, and other biological systems Targeting Wolbachia for biocontrol and disease eradication will have huge economic and medical benifits

References Stevens, L., Giordano, R., & Fialho, R. F. (2001). MALE-KILLING, NEMATODE INFECTIONS, BACTERIOPHAGE INFECTION, AND VIRULENCE OF CYTOPLASMIC BACTERIA IN THE GENUS WOLBACHIA. Annual Review of Ecology & Systematics, 32: 519 Hoerauf, A., Mand, S., Fischer, K., Kruppa, T., Marfo-Debrekyei, Y., Debrah, A., &... Bättner, D. W. (2003). Doxycycline as a novel strategy against bancroftian filariasis—depletion of Wolbachia endosymbionts from Wuchereria bancrofti and stop of microfilaria production. Medical Microbiology & Immunology... Study 3 Sofia Zabalou, Markus Riegler, Marianna Theodorakopoulou, Christian Stauffer, Charalambos Savakis, Kostas Bourtzis, John H. Law (2004). Wolbachia-Induced Cytoplasmic Incompatibility as a Means for Insect Pest Population Control. Proceedings of the National Academy of Sciences of the United States of America Vol. 101, No. 42 (Oct. 19, 2004), pp Study 1Wolbachia-Induced Cytoplasmic Incompatibility as a Means for Insect Pest Population ControlProceedings of the National Academy of Sciences of the United States of America Tortora, G., Funke, B., Case, C. (2010).Microbiology: An Introduction 10 th Ed Study 2 Hoerauf, A., Rao, R. U. (2007). Wolbachia: A Bug’s Life in another Bug

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