Directional alignment of different cell types organizes planar cell polarity

Area of Science:

• Cell biology
• Developmental biology
• Biophysics

Background:

• Planar cell polarity (PCP) is crucial for unidirectional epithelial cell polarization.
• PCP disruption occurs with imbalances in core PCP protein levels between adjacent cells.
• Some tissues maintain PCP despite varying core PCP protein abundance across cell types.

Purpose of the Study:

• To investigate how spatial cell-type distribution influences PCP maintenance under protein imbalance.
• To identify key features of tissue organization that confer robustness to PCP.

Main Methods:

• Utilized a pre-existing mathematical model of PCP.
• Performed systematic simulations to analyze PCP accuracy under protein imbalance.
• Applied deep learning and statistical modeling to identify critical organizational features.

Main Results:

• PCP maintenance accuracy under protein imbalance is highly dependent on cell-type distribution patterns.
• The orientation of cell-type alignment emerged as a critical determinant of PCP robustness.
• Directional cell-type alignment was observed in the mouse oviduct epithelium.

Conclusions:

• Tissue cell-type organization plays a significant, previously overlooked role in maintaining PCP.
• Directional alignment of cell types can enhance the robustness of PCP in the face of protein level variations.