Acetylecholine Binding to Nicotinic Acetylcholine Receptor

[FredericChopin]

I'm a bit confused about the details of how actylcholine (ACh) binds to its nicotinic acteylcholine receptor (nAChR).

I know that the nAChR has two alpha subunits that where the ligand (ACh) binds to. But is it one ACh molecule that binds to both alpha subunits, or is it two ACh molecules that each bind to one alpha subunit?

Thank you.

 

[Medicol]

...But is it one ACh molecule that binds to both alpha subunits, or is it two ACh molecules that each bind to one alpha subunit?...

For the receptor to get activated, only one ACh will make 2 non-covalent bonds with 2 subunits of the receptor in question.

 

[FredericChopin]

For the receptor to get activated, only one ACh will make 2 non-covalent bonds with 2 subunits of the receptor in question.

Thank you for your response.

It's really upsetting that there is so much contradictory and misleading information, like this site where they explicitly say that two ACh molecules bind to the receptor:

http://www.ebi.ac.uk/interpro/potm/2005_11/Page2.htm

I'm also taking a course in neuroscience, and although they don't explicitly say it, their diagrams also suggest two Ach molecules binding to the receptor (in the attachment).