Karl Palmquist, Biology

Ion flux controls heart asymmetry in Ciona intestinalis

During development, bilaterian organisms are patterned along the left-right axis. This left-right patterning results in organ asymmetry, which has crucial health relevance in humans. Due to the complexity of vertebrate organisms, we don’t have a comprehensive understanding of the different proteins involved in regulating organ asymmetry. To better understand what proteins and processes contribute to asymmetric organogenesis, we employ the tunicate Ciona intestinalis. We have found that the Ciona heart is positioned on the right side of developing juveniles. Asymmetric heart positioning is first observed during larval stages. Through inhibitor experiments, we have found that a process termed ion flux is necessary for proper heart positioning in both larvae and juveniles. Based on our findings, we hypothesize a model where ion flux directs heart asymmetry. These results provide the groundwork for future studies pinpointing the mechanisms underlying organ asymmetry in Ciona, with the ultimate goal of informing a comprehensive model for organ asymmetry in humans.