Ciliary Targeting of Olfactory CNG Channels Requires the CNGB1b Subunit and the Kinesin-2 Motor Protein, KIF17

• Published in: Current biology Vol. 16; no. 12; pp. 1211 - 1216
• Main Authors: Jenkins, Paul M., Hurd, Toby W., Zhang, Lian, McEwen, Dyke P., Brown, R. Lane, Margolis, Ben, Verhey, Kristen J., Martens, Jeffrey R.
• Format: Journal Article
• Language: English
• Published: England Elsevier Inc 20.06.2006
• Subjects: Amino Acid Sequence; Animals; Caenorhabditis elegans; Cell Line; CELLBIO; Cilia - metabolism; Cilia - ultrastructure; Cyclic Nucleotide-Gated Cation Channels; Dogs; Ion Channels - chemistry; Ion Channels - metabolism; Kinesin - metabolism; Luminescent Proteins - analysis; Molecular Motor Proteins - metabolism; Molecular Sequence Data; Protein Subunits - metabolism; Protein Transport; Sequence Alignment; CELLBIO
• ISSN: 0960-9822; 1879-0445
• DOI: 10.1016/j.cub.2006.04.034

Nonmotile cilia on olfactory sensory neurons (OSNs) compartmentalize signaling molecules, including odorant receptors and cyclic nucleotide-gated (CNG) channels, allowing for efficient, spatially confined responses to sensory stimuli [1–3]. Little is known about the mechanisms of the ciliary targeting of olfactory CNG channels, composed of three subunits: CNGA2, CNGA4, and CNGB1b [4]. Recent reports suggest that subunit composition of the retinal CNG channel influences localization, leading to disease [5, 6]. However, the mechanistic role of subunits in properly targeting native olfactory CNG channels remains unclear. Here, we show that heteromeric assembly with CNGB1b, containing a critical carboxy-terminal motif (RVxP), is required for ciliary trafficking of olfactory CNG channels. Movement of proteins within the cilia is governed by intraflagellar transport (IFT), a process that facilitates bidirectional movement of cargo along microtubules [7, 8]. Work in C. elegans has established that heterotrimeric and homodimeric kinesin-2 family members play a critical role in anterograde transport [9–11]. In mammalian systems, the heterotrimeric KIF3a/KIF3b/KAP-3 complex plays a clear role in IFT; however, no role has been established for KIF17, the mammalian homolog of OSM-3 [12]. Here, we demonstrate that KIF17 is required for olfactory CNG channel targeting, providing novel insights into mechanisms of mammalian ciliary transport.