Ankyrin-G promotes cyclic nucleotide-gated channel transport to rod photoreceptor sensory cilia.
Cyclic nucleotide-gated (CNG) channels localize exclusively to the plasma membrane of photosensitive outer segments of rod photoreceptors where they generate the electrical response to light. Here, we report the finding that targeting of CNG channels to the rod outer segment required their interaction with ankyrin-G. Ankyrin-G localized exclusively to rod outer segments, coimmunoprecipitated with the CNG channel, and bound to the C-terminal domain of the channel beta1 subunit. Ankyrin-G depletion in neonatal mouse retinas markedly reduced CNG channel expression. Transgenic expression of CNG channel beta-subunit mutants in Xenopus rods showed that ankyrin-G binding was necessary and sufficient for targeting of the beta1 subunit to outer segments. Thus, ankyrin-G is required for transport of CNG channels to the plasma membrane of rod outer segments.
Kizhatil
Krishnakumar
K
Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA.
Baker
Sheila A
SA
Arshavsky
Vadim Y
VY
Bennett
Vann
V
D000595:Amino Acid Sequence; D000818:Animals; D030801:Animals, Genetically Modified; D017487:Ankyrins / Q000378:metabolism*; D002417:Cattle; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D002923:Cilia / Q000378:metabolism*; D054815:Cyclic Nucleotide-Gated Cation Channels / Q000378:metabolism*; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012374:Rod Cell Outer Segment / Q000378:metabolism*; D014982:Xenopus laevis
C094681:Ank3 protein, mouse; D017487:Ankyrins; C518235:CNGB1 protein, human; C529481:Cngb1 protein, mouse; D054815:Cyclic Nucleotide-Gated Cation Channels; D009419:Nerve Tissue Proteins; D011993:Recombinant Fusion Proteins