Cassandra Extavour awarded HSFP Program Award 2022 Research Grant

September 5, 2022
Cassandra Extavour. Credit: Erica Derrickson 2020

Professor Cassandra Extavour has been awarded an Early Career Grant from the 2022 Human Frontier Science Program (HFSP). The award is presented to Extavour in collaboration with Dr. Pavel Tomancak, MPI-CBG Dresden, Dr. Carl-Philipp Heisenberg, Institute of Science and Technology Austria, and Dr. Andreas Hejnol, University of Bergen. The three-year project titled, Bridging biophysics and evolution: impact of intermediate filament evolution on tissue mechanics, will address the many ways in which cells change shape and coordinate their behaviors in groups.

Darwin said, "Life has an amazing ability to create shapes. Animals excel at generating “endless forms, most beautiful.” They do this by coordinating cellular behaviors in the process known as morphogenesis. Although researchers have a solid understanding of many morphogenetic processes, very little is known about how these processes evolved from their origins in unicellular ancestors to give rise to the morphological diversity seen in nature today. To better understand these processes, the team will study morphogenesis broadly across the tree of life. The project will make use of the fully resolved animal phylogeny as a solid theoretical framework for understanding morphogenesis and bring biophysical concepts and approaches to the studies of evolution of development (evo-devo).

“Fundamentally, biology is an expression of physics. We argue that we need to understand how biology exploits physics to create shape and form during evolution. To tackle these questions, we will build a bridge between evo-devo and tissue morphogenesis research fields which are relatively isolated,” said Extavour.

Currently research into how development evolves focuses primarily on understanding how gene regulatory networks change between species. The tissue morphogenesis field, on the other hand, puts emphasis on understanding the effector molecules and mechanisms that cells use to change their behavior and collectively sculpt embryonic tissue during development. “Evolutionary developmental biology is by definition rather open to exploring the diversity of life and actively exploits non-traditional models,” said Extavour, “tissue morphogenesis researchers, by contrast, tend to limit their investigation to well-described biological model systems where complete genetic and embryological toolkits exist. This model organism bias severely limits progress in the tissue morphogenesis field.”

The lack of studies examining the mechanistic understanding of the actual dynamic morphogenetic events across a broad range of species, hinders understanding of how development evolves. To answer this, the team’s proposal rests on the realization that to truly reveal how morphogenesis works and evolves, they will need to combine the technological and conceptual approaches of both the evo-devo and tissue morphogenesis.

“We have assembled a powerful group of interdisciplinary researchers interested in making the connections between tissue morphogenesis and evo-devo, and open to studying the evolution of morphogenesis on a mechanistic level using a comparative approach,” said Extavour.

Cassandra Extavour (HHMI Investigator) is a leading scientist in the evo-devo field with keen interest in the evolution of the genetic mechanisms employed during early animal embryogenesis to specify cell fate, development and differentiation. Carl-Philipp Heisenberg is a developmental biologist leading the field of tissue morphogenesis. Heisenberg uses imaging, physical modeling and embryological manipulation to study gastrulation in zebrafish and ascidians. Andreas Hejnol is a zoologist known for uncompromisingly using the comparative approach on upwards of 15 distinct animal phyla to study the evolution of early development through imaging-based developmental lineaging and gene expression analysis. Pavel Tomancak developed genome-scale image-based gene expression resources in Drosophila, and uses light sheet microscopy and advanced image analysis to apply the comparative approach to developmental morphogenesis of multiple phyla.

“Our team collectively possesses the range of expertise necessary to successfully bridge the evo-devo and tissue morphogenesis fields,” said Extavour. “Together we  create a potential for synergistic discovery that is stronger than the sum of its parts, combining non-traditional model species, phylogenomics, molecular genetic analysis, imaging, biophysical manipulation, image analysis and modeling."

The Human Frontier Science Program is an international program funded by 13 countries and the European Union. HFSP was established in 1989 to encourage international collaboration on basic research topics
See also: Faculty News, 2022