Analysis of Biomechanical Stresses During Zebrafish Brain Morphogenesis
Mentor 1
Gutzman Jennifer
Start Date
28-4-2023 12:00 AM
Description
Structural birth defects of the brain can result in physical or mental impairments ranging from minor neurological effects to significant disability or early fatality. These morphological abnormalities often result from disruption in fundamental biological processes due to either genetic mutations or environmental factors. Abnormal tissue mechanics also contribute to structural defects during development. While significant work has been conducted to understand the biochemical pathways that mediate cell and tissue shape during development, there is a significant gap in our understanding of the biophysical and biomechanical mechanisms that drive morphogenetic events in vivo. Using the optically transparent zebrafish (Danio rerio) embryonic model, we are investigating the biomechanics of morphogenesis in the well characterized and highly conserved midbrain-hindbrain boundary (MHB), which develops into the cerebellum and tectum. In order to measure biomechanical stresses in the developing brain, we have been using an oil microdroplet mechanosensor method. We label all embryonic cells with membrane associated green fluorescent protein (memGFP). Then, at the start of MHB morphogenesis, we inject the oil mechanosensor into the presumptive MHB and let the embryos develop. After MHB formation, we image the live brain with the oil droplet using confocal microscopy. We reconstruct the drop in 3D, and we can extrapolate tissue stress measurements from any drop deformation using the STRESS program in Matlab. We have found that there is significantly more tissue stress in the ventral MHB constriction compared to surrounding regions. Our future work will examine embryonic mutants to identify molecules within the cells and outside of the tissue that are required for the stress needed to fold the MHB. Our work to identify the contribution of biomechanics to morphogenesis of the brain will significantly impact our understanding of the unknown mechanisms that lead to congenital morphological diseases that have not previously been explored.
Analysis of Biomechanical Stresses During Zebrafish Brain Morphogenesis
Structural birth defects of the brain can result in physical or mental impairments ranging from minor neurological effects to significant disability or early fatality. These morphological abnormalities often result from disruption in fundamental biological processes due to either genetic mutations or environmental factors. Abnormal tissue mechanics also contribute to structural defects during development. While significant work has been conducted to understand the biochemical pathways that mediate cell and tissue shape during development, there is a significant gap in our understanding of the biophysical and biomechanical mechanisms that drive morphogenetic events in vivo. Using the optically transparent zebrafish (Danio rerio) embryonic model, we are investigating the biomechanics of morphogenesis in the well characterized and highly conserved midbrain-hindbrain boundary (MHB), which develops into the cerebellum and tectum. In order to measure biomechanical stresses in the developing brain, we have been using an oil microdroplet mechanosensor method. We label all embryonic cells with membrane associated green fluorescent protein (memGFP). Then, at the start of MHB morphogenesis, we inject the oil mechanosensor into the presumptive MHB and let the embryos develop. After MHB formation, we image the live brain with the oil droplet using confocal microscopy. We reconstruct the drop in 3D, and we can extrapolate tissue stress measurements from any drop deformation using the STRESS program in Matlab. We have found that there is significantly more tissue stress in the ventral MHB constriction compared to surrounding regions. Our future work will examine embryonic mutants to identify molecules within the cells and outside of the tissue that are required for the stress needed to fold the MHB. Our work to identify the contribution of biomechanics to morphogenesis of the brain will significantly impact our understanding of the unknown mechanisms that lead to congenital morphological diseases that have not previously been explored.
