Planar cell polarity complex internalization is dependent on Celsr1 cis-dimerization
Sarah G Latario1,2, Thomas Saba1,2, Brandon Trejo3
1Biomedical Sciences Graduate Program, Penn State College of Medicine, Hershey, PA, USA.
Iscience
|July 26, 2026
Summary
Planar cell polarity (PCP) is maintained during cell division by internalizing protein complexes. Celsr1 dimerization is crucial for this process, ensuring tissue polarity is restored after cell division.
Area of Science:
- Cell Biology
- Developmental Biology
- Tissue Polarity
Background:
- Planar cell polarity (PCP) organizes cell orientation within tissues.
- PCP relies on transmembrane proteins like Celsr1, Fz6, and Vangl2.
- Epidermal basal cells divide while maintaining tissue polarity.
Purpose of the Study:
- Investigate how PCP is maintained during embryonic mouse epidermis cell division.
- Determine the role of Celsr1 in PCP complex internalization and tissue polarity restoration.
Main Methods:
- Analysis of Celsr1Crsh/Crsh mutant mouse epidermis.
- In vitro mixed-cell assays to study protein interactions.
- Investigating Celsr1 dimerization and its effect on endocytosis.
Main Results:
- Aberrant internalization of Celsr1 and Fz6, with failed Vangl2 co-internalization in mutants.
- Crsh deficiency impairs trans-endocytosis of Celsr1 and Vangl2.
- Forced Crsh dimerization rescues internalization defects.
Conclusions:
- Celsr1 dimerization is essential for PCP complex establishment and maintenance.
- A Celsr1 dimerization-dependent mechanism controls tissue polarity during cell division via trans-endocytosis.
- This study elucidates a novel mechanism for maintaining tissue integrity during development.
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