Martin Lab research summary

“It is not birth, marriage, or death, but gastrulation, which is truly the most important time in your life.”

Lewis Wolpert

To form a complex organ, simple tissues must be folded, stretched, compressed, and otherwise sculpted into a precise form in a process called tissue morphogenesis. One of the most dramatic examples of tissue morphogenesis occurs during embryonic development, when primitive planar tissues are folded to generate separate layers that will give rise to different parts of the body during gastrulation. Tissue morphogenesis requires that cytoskeletal machines generate forces that change cell shape and deform the tissue. The molecular mechanism by which the cytoskeleton generates force is not known for many of the diverse cell shape changes and tissue movements that underlie morphogenesis. Furthermore, how force generation by hundreds or thousands of cells is coordinated by biochemical and mechanical signals in a tissue is an important step to understand how cells collectively deform a tissue.

The Martin lab is interested in how tissues get their shape. Given that tissue morphogenesis fundamentally involves movement, we have developed a system to visualize and quantify the dynamics of molecules, cells, and tissues during gastrulation. We focus on mesoderm invagination in the fruit fly, Drosophila melanogaster, because cell shape changes and cytoskeletal dynamics can be readily imaged by confocal microscopy during a process that occurs on the time scale of minutes. Live imaging can be combined with genetic (mutants, RNAi), cell biological (drug injections), computational (image segmentation and analysis), biophysical (laser cutting), and biochemical (complex purification) approaches to functionally dissect cell shape change in the embryo.