Botryllus schlosseri is a colonial tunicate with a number of unique biological features, making it an accessible model organism for a variety of studies.

Allorecognition is the ability of an individual to discriminate its own cells and tissues from those of another individual, and is the process that controls the acceptance or rejection of transplanted tissues in the clinic. Botryllus undergoes a natural transplantation reaction controlled by a highly polymoprhic allorecognition system, and we are dissecting the molecular mechanisms that underlie this interaction.

Every week, a Botryllus colony is in the process of regenerating all somatic and germline tissues, thus developmental processes, such formation and seeding of a germline niche, also occur weekly. Germline stem cells in Botryllus compete for niche occupancy, and there is natural genetic variability in this process that we can use to study stem cell homing and niche interactions.

Botryllus has a large extracorporeal vascular network that allows direct visualization and manipulation of blood vessels. We are currently studying the role of the extracellular matrix during branching morphogenesis and remodeling of the vasculature.

Colonial ascidians are the only chordates with the ability to regenerate every organ in their body, and in Botryllus this takes place every week of its 2-5 year lifespan. Utilizing this model, we can compare and contrast embryogenesis and asexual development to understand how developmental processes such as patterning and axis formation are accomplished during regeneration. This constant state of regeneration also has impact on how an individual ages .