A novel, PCP-dependent tissue organising principle coordinating morphogenesis between embryonic skin epidermal layers

Area of Science:

• Developmental Biology
• Cell Biology
• Genetics

Background:

• Planar cell polarity (PCP) establishes directional information within tissues.
• In developing mouse skin, PCP guides cell behavior in the basal epidermis.
• A multi-layered tissue organization principle coordinating cell orientation across epidermal layers is investigated.

Purpose of the Study:

• To investigate a novel, three-dimensional PCP protein-dependent tissue organizing principle in mouse embryonic epidermis.
• To analyze the role of Frizzled-6 (Fz6) in coordinating cell long axis orientation across multiple epidermal layers.
• To understand the establishment of epidermal cell orientation symmetry and directional switching.

Main Methods:

• Analysis of Frizzled-6 (Fz6) in developing mouse trunk epidermis.
• Examination of fz6 mouse mutant skin.
• Microscopic analysis of cell arrays and rosette-type arrangements.

Main Results:

• Frizzled-6 (Fz6) is present in multiple epidermal layers.
• Fz6 signaling is crucial for coordinating cell long axis orientation between epidermal layers.
• Fz6 influences the timing of orientation switching between circumferential and longitudinal axes.
• Fz6 establishes mirror symmetry of cell orientation across the ventral midline.

Conclusions:

• A novel, 3D PCP-dependent tissue organizing principle coordinates cell orientation across epidermal layers in mouse embryonic skin.
• Frizzled-6 (Fz6) plays a key role in this process, influencing orientation, timing, and symmetry.
• Local cell arrangements and potential 3D tissue polarity mechanisms underlie epidermal morphogenesis.