Hacker News new | ask | show | jobs
by Duller-Finite 1822 days ago
This is truly a landmark study. This is the first structure of any odorant receptor. It is, however, one from an insect, so the structure is not homologous to mammalian olfactory receptors, which are a large family of G-protein-coupled receptors.
1 comments

Forgive my ignorance, but I am wondering if this is all that different. GPCRs typically downstream towards ion channels, right? So even if insect physiology relies on ligand gated ion channels, is the end result the same, just more metabolically expensive in mammals?
Not really. GPCRs amplify signals at each step via their second messenger cascade. These channels form homotetramers whose structure differs greatly from the canonical seven transmembrane domain structure of GPCRs. So this study is important since there were no studies indicating how odorants bind and activate odorant receptors. However, it is unlikely that the mechanisms in insects odorant receptors will directly apply to those of mammalian odorant receptors. In contrast, mammalian odor receptors will work much more like those of other class A GPCRs like the β-adrenergic receptor, of which there are numerous structures interacting with ligands and in various configurations, and which was the basis of the work that won the nobel prize in 2012.