Regulator of G-protein signaling 22 (RGS22) is a metazoa-specific radial spoke component required for coordinated ciliary beating

ABSTRACT: Metazoan motile cilia, transcending their protozoan origins, have achieved a higher-order function to orchestrate tissue-wide coordinated beating that drives unidirectional fluid flows. Whether radial spokes (RSs), which mediate mechano-signal transduction between the central pair and axonemal dynein arms, acquire metazoan-specific subunit(s) for this in evolution, however, remains poorly known. Here, we report that RGS22, a member of the Gα-GTPase activating protein family, is a metazoan-specific structural component of RS1/2 complexes. Mice lacking RGS22 exhibit ultrastructural defects in motile cilia including partial loss or tilting of the RS1 distal head and disorganization of outer dynein arms. These abnormalities correlate with impaired planar polarity, manifested as unsynchronized ciliary beating and disrupted rotational polarity of basal bodies across the ependyma. Over time, the motility deficits lead to progressive ciliary loss and shortening, culminating in mild to severe congenital hydrocephalus. Taken together, our findings provide physiological evidence that RGS22 is diverged from its family members during protozoa-to-metazoa evolution to modulate the RS architecture for coordinated ciliary beating.

ORGANISM(S): Mus Musculus

SUBMITTER: Qianting Zhang  

PROVIDER: PXD075304 | iProX | Fri Mar 06 00:00:00 GMT 2026

REPOSITORIES: iProX