Undergraduate Research Showcase

Quantifying Myosin Networks and Their Roles in Morphogenesis
Cole Allan, cja2160@columbia.edu
SEAS ‘21, Mechanical Engineering, Columbia University
Supervising Faculty, Sponsor, and Location of Research
Dr. Karen Kasza, Bonomi Summer Scholar, Kasza Living Materials Laboratory,
Columbia University
Abstract
Morphogenesis is a process during embryonic development in which cells and/or tissues
develop their shape. These morphogenetic events utilize a network of motor proteins,
non-muscle myosin II, to generate forces. Thus, being able to identify and characterize
this network makes it possible to synthetically control tissue folding, and, potentially in
the future, build robust tissue architectures out of 2-dimensional tissue sheets. The goal of
this study, completed virtually in the Kasza Living Materials Laboratory, was to develop
a software tool that would identify the myosin networks within Drosophila embryos at
various stages of development and to quantitatively assess how the myosin networks
influence the propensity of tissues to remodel. Using confocal microscopy, supracellular
myosin networks were fluorescently tagged in high resolution movies. Some of the
properties analyzed in the developed software include measuring the network
connectivity, measuring the flexibility of each network edge, and identifying regions of
rapidly changing myosin. These properties are essential to characterize the structure of
myosin networks. Specifically, we found that myosin segments became less tortuous
when there was tissue elongation in the same orientation. Additionally, the cell velocity
was tracked to identify distinct regions of tissue that behaved more fluid-like. In the
future, with this understanding of myosin networks and cellular movement, we are
hopeful that we will be able to coordinate cell behavior and manipulate the mechanical
properties within tissues.
Keywords
Morphogenesis, Drosophila melanogaster, Myosin Networks
4