Meeting Abstract

P1.62  Jan. 4  Cadherin2: Roles in cardiovascular development and cardiac regeneration BAGATTO, B; HISSETT, E*; LIU, Q; University of Akron; University of Akron; University of Akron bagatto@uakron.edu

Cadherins are cell surface adhesion molecules that play important roles in development of vertebrate tissues and organs. We studied cadherin2 expression in developing zebrafish heart using in situ hybridization and immunocytochemical methods, and we found that cadherin2 was strongly expressed by the myocardium of the embryonic zebrafish. To gain insight into cadherin2 role in the formation and function of the heart, we analyzed cardiac differentiation and performance in a cadherin2 mutant, glass onion (glo). We found that the cadherin2 mutant had enlarged pericardial cavity, disorganized atrium and ventricle, and reduced expression of a ventricular specific marker vmhc. Individual myocardiocytes in the glo mutant embryos become round shaped and loosely aggregated. In vivo measurements of cardiac performance reveal that the mutant heart has significantly reduced heart rate, stroke volume and cardiac output compared to control embryos. We have also shown that cadherin2 is an essential molecule in the regeneration of cardiac tissue following injury. Overall, our results suggest that cadherin2 plays an essential role in zebrafish cardiovascular development and regeneration. Although the exact mechanisms remain unknown as to the formation of the enlarged pericardium and reduced peripheral blood flow, it is clear that physiological cardiovascular performance is impaired when cadherin2 function is disrupted.