Mechanisms of Wolbachia Stem Cell Niche Tropism

Trustees Of Boston University, Boston

Investigators

Abstract

In addition to its presence in filarial nematode worms and several non-insect arthropods, the bacterium Wolbachia infects more than one million insect species, or about two-thirds of all described insect taxa; by virtue of its widespread distribution alone, it is the most common intracellular bacterium on earth. Wolbachia also has profound ecological and evolutionary effects on the reproduction of its animal hosts, as well as other important biological consequences. The primary means of transmission of Wolbachia from host to host is vertical (hereditary) transmission, through passage from the adult female host ovary to the offspring via the egg; there is also evidence of horizontal (non-hereditary) transmission of Wolbachia among hosts. Given the biological importance of this symbiotic bacterium, both for basic research and for its applied potential in insect control, it is remarkable that so little is known about the mechanism by which Wolbachia infects insect host cells. The aim of this project is to elucidate this mechanism. In earlier research, the investigator has shown that Wolbachia targets specific cell types in the insect ovary, particularly the cellular environment supporting the stem cells (aka stem cell niche) of insect ovaries during both horizontal and vertical transmission. Bringing a suite of novel imaging and molecular tools to bear on the problem, the investigator now plans to characterize the detailed mechanism by which this targeting (tropism) of stem-cell-niches occurs. In addition to its strong importance for understanding the biology of Wolbachia and the dynamics of hereditarily-transmitted symbioses in general, this project also will contribute fresh perspectives on the biology of stem cells. The project includes research training and education on stem-cell and symbiosis biology for students from high-school through graduate levels, including outreach workshops specifically targeted to high-school girls and students from under-represented minorities.