Daniel Lai, Biology

Secretory Pathway Contribution to Seamless Tube Formation in the Drosophila Tracheal System

Many of our organs are made up of biological tubes (think heart, lungs, gut, and kidneys). We are specifically interested in the process of angiogenesis, the formation of blood vessels early on in human development and after injury. To better understand how such biological tubes form in humans, we turn to a simpler organism, Drosophila melanogaster (the common fruit fly), to investigate proteins and pathways involved in tube morphogenesis. Highly branched terminal cells at the end of the Drosophila trachea form single-celled tubes with a “seamless” morphology, a characteristic of many angiogenic sprouts in humans as well. We investigated how the late secretory pathway, a common cellular process, contributes to seamless tube formation. We determined that disrupting various components of the late secretory pathway leads to similar tube defects in terminal cells. Our findings support a role for late secretory pathway events in expanding seamless tubes during terminal cell formation and provide a biological basis for developing a model of seamless tube formation in humans.