The developing chick embryo undergoes a series of complex shape changes called morphogenesis. Although the genetic and molecular aspects of morphogenesis are well-studied, scant attention is paid to the mechanical aspects. In particular, the driving forces behind the dramatic shape changes during embryo development are poorly understood. This project considers two often-overlooked, but critically important shape changes that occur during early embryo development: (1) body flexion, which curves the initially straight embryonic body axis and (2) body torsion, which rotates it. Flexion and torsion are necessary for proper development of important organs such as the heart. The forces driving flexion and torsion are not currently known and understanding them is the goal of this project. This research will train numerous undergraduate students in all aspects of research. Science outreach, particularly to under-represented minorities, is another critical aspect of this project. It includes a formal collaboration with Union College?s Science and Technology Entry Program, which introduces underrepresented minority and economically disadvantaged students in grades 7-12 to STEM fields.
A combined experimental and computational approach is used to determine the forces driving flexion and torsion. The chick embryo is used as the experimental model. Light microscopy and optical coherence tomography will be used to qualitatively and quantitatively characterize flexion and torsion in the developmental stages under consideration. Atomic force microscopy will be used to probe the mechanical environment of the regions undergoing flexion and torsion. And chemical and biomechanical perturbations will be used to study these processes further. The finite element method will be used to develop the computational model which will be validated by comparing experimental and model-predicted global and local shape changes. The validated model will be used for hypothesis testing to determine the forces driving flexion and torsion.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
