How do cells fit in? Understanding the mechanisms underlying epithelial morphogenesis

Date

Sep 21, 2023

Time

3:00 PM - 4:00 PM

Speaker

Guilherme Bastos Ventura

Affiliation

University of Copenhagen Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW)

Language

en

Main Topic

Biologie

Host

Claudia Gerri

Description

During embryonic development, tissues evolve into intricate collectives that combine different specialized cell types. To create such complex ensembles, specialized precursor cells often move to integrate the target tissues where they execute their function. While much is known about the biochemical signals controlling cell movement in vivo, comparatively little is known about how mechanical stimuli from the environment direct migrating precursors. To address this question, we focus on the specialized precursor cells integrating the epidermis of the Xenopus embryo, using quantitative live imaging and mathematical modeling to characterize this process. Here, we describe how, during integration, the multiciliated cell (MCC) precursors extend actin-based filopodia directed at the epithelial vertices of neighboring epidermal cells. As the integrating precursors interact with their neighbors, they pull on the epithelial vertices through a mechanism that depends on the force generating motor myosin-II and the activity of a novel regulator of cell integration, LSR. To interpret our in vivo findings, we have designed a theoretical framework that models the physical environment of the epidermis during precursor integration. Our model and experimental data show that MCC precursors pull at the epithelial vertices to probe the local mechanical properties and identify suitable positions for cell integration. This pulling mechanism also equips MCC precursors with the ability to actively remodel their neighbors, and effectively generate a permissive environment that facilitates integration. Altogether, our work defines a novel durotaxis-like mechanism driving the integration of specialized precursors within a developing tissue, and highlights how individual migrating precursors can act as drivers of morphogenesis.

Last modified: Sep 22, 2023, 7:37:38 AM