Morphogens enable interacting supracellular phases that generate organ architecture.

Area of Science:

• Developmental Biology
• Biophysics
• Tissue Engineering

Background:

• Morphogen gradients are crucial for vertebrate organogenesis, guiding complex tissue formation.
• Understanding how cellular-level morphogen signals translate to tissue-level behaviors is a key challenge.

Purpose of the Study:

• To investigate the influence of morphogens on supracellular organization in avian skin development.
• To differentiate between cellular-scale morphogen effects and their emergent supracellular functions.

Main Methods:

• Physical measurements across multiple length scales in avian skin.
• Analysis of material property changes induced by fibroblast growth factor (FGF) and bone morphogenetic protein (BMP).

Main Results:

• Morphogen-induced material property differences were amplified at the supracellular scale compared to the cellular scale.
• FGF promoted tissue "solidification," while BMP enhanced fluidity and mechanical activity at the supracellular level.
• These differential effects led to the formation of basement membrane-less compartments, priming tissues for budding.

Conclusions:

• Morphogen actions have distinct proximal (cellular) and emergent (supracellular) effects.
• Supracellular material properties regulated by FGF and BMP are critical for driving avian skin tissue morphogenesis.