Date of Award
Infertility and impaired fecundity affect 8.2 million women in the United States. Intercellular bridges are essential to the proper formation of germ cells in many organisms; therefore, learning more about how they are formed and regulated during the formation of sperm and eggs could provide insight into how defects in their structure can impact fertility. Intercellular bridges are actin-rich structures that connect developing germ cells to each other and allow the transfer of materials. I used the development of the fruit fly egg as a model system to study formation and regulation of intercellular bridges. Specifically, I investigated the role of an actin nucleating protein complex located at the ring canals, Arp2/3, in the formation and expansion of these structures. The objective of this work is to characterize the effect of depletion, mutation, or inhibition of the Arp2/3 complex on the structure and growth of these intercellular bridges, called ring canals. Because ring canals are rich in actin and actin-binding proteins, I predicted that if Arp2/3 levels are altered, then ring canal formation and/or growth will be affected. When levels of Arp2/3 complex proteins were reduced or if the complex was chemically inhibited, ring canals are significantly smaller than in controls; this difference was more pronounced in later stages of oogenesis (stages 7-10b), suggesting Arp2/3 plays a role in ring canal structure and stability in later stages of oogenesis. Because these structures are found in organisms from insects to humans, research on the Arp2/3 complex provides valuable understanding of intercellular bridge structure and function that can be applied to higher organisms and our understanding of infertility.
Tipold, Marina, "The Role of Arp2/3 in Ring Canal Development in Drosophila melanogaster" (2016). Undergraduate Honors Thesis Collection. 345.