Elementary response of olfactory receptor neurons to odorants.


Journal Article

Signaling by heterotrimeric GTP-binding proteins (G proteins) drives numerous cellular processes. The number of G protein molecules activated by a single membrane receptor is a determinant of signal amplification, although in most cases this parameter remains unknown. In retinal rod photoreceptors, a long-lived photoisomerized rhodopsin molecule activates many G protein molecules (transducins), yielding substantial amplification and a large elementary (single-photon) response, before rhodopsin activity is terminated. Here we report that the elementary response in olfactory transduction is extremely small. A ligand-bound odorant receptor has a low probability of activating even one G protein molecule because the odorant dwell-time is very brief. Thus, signal amplification in olfactory transduction appears fundamentally different from that of phototransduction.

Full Text

Cited Authors

  • Bhandawat, V; Reisert, J; Yau, K-W

Published Date

  • June 2005

Published In

Volume / Issue

  • 308 / 5730

Start / End Page

  • 1931 - 1934

PubMed ID

  • 15976304

Pubmed Central ID

  • 15976304

Electronic International Standard Serial Number (EISSN)

  • 1095-9203

International Standard Serial Number (ISSN)

  • 0036-8075

Digital Object Identifier (DOI)

  • 10.1126/science.1109886


  • eng