RRC ID 46089
Author Mohan S, Timbers TA, Kennedy J, Blacque OE, Leroux MR.
Title Striated rootlet and nonfilamentous forms of rootletin maintain ciliary function.
Journal Curr Biol
Abstract Primary cilia are microtubule-based sensory organelles whose structures and functions must be actively maintained throughout animal lifespan to support signal transduction pathways essential for development and physiological processes such as vision and olfaction [1]. Remarkably, few cellular components aside from the intraflagellar transport (IFT) machinery are implicated in ciliary maintenance [2]. Rootletin, an evolutionarily conserved protein found as prominent striated rootlets or a nonfilamentous form, both of which are associated with cilium-anchoring basal bodies, represents a likely candidate given its well-known role in preventing ciliary photoreceptor degeneration in a mouse model [3, 4]. Whether rootletin is universally required for maintaining ciliary integrity, and if so, by what mechanism, remains unresolved. Here, we demonstrate that the gene disrupted in the previously isolated C. elegans chemosensory mutant che-10 encodes a rootletin ortholog that localizes proximally and distally to basal bodies of cilia harboring or lacking conspicuous rootlets. In vivo analyses reveal that CHE-10/rootletin maintains ciliary integrity partly by modulating the assembly, motility, and flux of IFT particles, which are critical for axoneme length control. Surprisingly, CHE-10/rootletin is also essential for stabilizing ciliary transition zones and basal bodies, roles not ascribed to IFT. Unifying these findings, we provide evidence that the underlying molecular defects in the che-10 mutant stem from disrupted organization/function of the periciliary membrane, affecting the efficient delivery of basal body-associated and ciliary components and resulting in cilium degeneration. Together, our cloning and functional analyses of C. elegans che-10 provide the first mechanistic insights into how filamentous and nonfilamentous forms of rootletin play essential roles in maintaining ciliary function in metazoans.
Volume 23(20)
Pages 2016-22
Published 2013-10-21
DOI 10.1016/j.cub.2013.08.033
PII S0960-9822(13)01039-7
PMID 24094853
MeSH Animals Caenorhabditis elegans / genetics Caenorhabditis elegans / metabolism* Caenorhabditis elegans Proteins / genetics Caenorhabditis elegans Proteins / metabolism* Cilia / metabolism Flagella / metabolism* Microscopy, Fluorescence Mutation Protein Transport
IF 9.601
Times Cited 21
WOS Category BIOCHEMISTRY & MOLECULAR BIOLOGY CELL BIOLOGY
Resource
C.elegans tm2816