Send to

Choose Destination
Neuron. 2004 May 13;42(3):411-21.

Stoichiometry and assembly of olfactory cyclic nucleotide-gated channels.

Author information

Howard Hughes Medical Institute, Department of Physiology and Biophysics, Box 357290, University of Washington School of Medicine, Seattle, WA 98195 USA.


Native ion channels are precisely tuned to their physiological role in neuronal signaling. This tuning frequently involves the controlled assembly of heteromeric channels comprising multiple types of subunits. Cyclic nucleotide-gated (CNG) channels of olfactory neurons are tetramers and require three types of subunits, CNGA2, CNGA4, and CNGB1b, to exhibit properties necessary for olfactory transduction. Using fluorescently tagged subunits and fluorescence resonance energy transfer (FRET), we find the subunit composition of heteromeric olfactory channels in the surface membrane is fixed, with 2:1:1 CNGA2:CNGA4:CNGB1b. Furthermore, when expressed individually with CNGA2, CNGA4 and CNGB1b subunits were still present in only a single copy and, when expressed alone, did not self-assemble. These results suggest that the precise assembly of heteromeric olfactory channels results from a mechanism where CNGA4 and CNGB1b subunits have a high affinity for CNGA2 but not for self-assembly, precluding more than one CNGA4 or CNGB1b subunit in the channel complex.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center