β-Arrestin 1 mediates non-canonical Wnt pathway to regulate convergent extension movements

Area of Science:

• Developmental Biology
• Cell Signaling
• Molecular Biology

Background:

• Beta-arrestins (β-arrestins) are key regulators of G protein-coupled receptor (GPCR) signaling, involved in desensitization and internalization.
• Non-canonical Wnt signaling pathways, independent of β-catenin, are crucial for embryonic development, particularly cell rearrangements.

Purpose of the Study:

• To investigate the role of β-arrestin 1 as a mediator of β-catenin-independent (non-canonical) Wnt signaling.
• To elucidate the function of Xenopus β-arrestin 1 (xβarr1) in early embryonic development, specifically in cell movements.

Main Methods:

• Utilized Xenopus embryos for gain- and loss-of-function analyses of xβarr1.
• Performed rescue experiments to validate the signaling pathway.
• Investigated interactions between xβarr1 and Wnt pathway components (Ryk, Fz, Dishevelled).

Main Results:

• xβarr1 regulates convergent extension (CE) movements in mesodermal tissues without affecting cell fate specification.
• xβarr1 acts downstream of Wnt11/Fz7 signaling and activates RhoA and JNK pathways.
• xβarr1 interacts with Ryk, Fz, and Dishevelled, key components of Wnt signaling.
• xβarr1 and xβarr2 exhibit interchangeable endocytic activity in regulating CE movements.

Conclusions:

• β-arrestin 1 is a critical mediator of non-canonical Wnt signaling, controlling cell rearrangements during embryonic development.
• β-arrestin 1 and β-arrestin 2 possess interchangeable endocytic functions essential for convergent extension movements.