Journal Article

Emergent cellular self-organization and mechanosensation initiate follicle pattern in the avian skin

Kumar, Sanjay, Rodrigues, Alan R., Shyer, Amy E., Harland, Richard M., Schroeder, Grant G., Kassianidou, Elena

2017

Overview

The spacing of hair in mammals and feathers in birds is one of the most apparent morphological features of the skin. This pattern arises when uniform fields of progenitor cells diversify their molecular fate while adopting higher-order structure. Using the nascent skin of the developing chicken embryo as a model system, we find that morphological and molecular symmetries are simultaneously broken by an emergent process of cellular self-organization. The key initiators of heterogeneity are dermal progenitors, which spontaneously aggregate through contractility-driven cellular pulling. Concurrently, this dermal cell aggregation triggers the mechanosensitive activation of β-catenin in adjacent epidermal cells, initiating the follicle gene expression program. Taken together, this mechanism provides a means of integrating mechanical and molecular perspectives of organ formation.

• Publisher: American Association for the Advancement of Science,The American Association for the Advancement of Science
• Subject: Animals / beta Catenin - metabolism / Birds / Cell aggregation / Cells (biology) / Chick Embryo / Chickens / Contractility / Epidermal Cells / Epidermis - embryology / Feathers / Feathers - cytology / Feathers - embryology / Gene expression / Gene Expression Regulation, Developmental / Hair / Heterogeneity / Initiators / Mechanotransduction / Mechanotransduction, Cellular / Molecular structure / Morphology / Organogenesis / Organogenesis - genetics / Organogenesis - physiology / Skin / Stem cells / Stem Cells - cytology / Stem Cells - physiology / β-Catenin