Abstract
A photoactivatable analog of phosphatidylserine, 125I-labeled 4-azidosalicylic acid-phosphatidylserine ( 125I-ASA-PS) (Blanton, M. and Wang, H.H. (1990) Biochemistry 29, 1186–1194) was used to label the nicotinic acetylcholine receptor. The photoactivatable group of 125I-ASA-PS is attached directly to the phospholipid head group making it an excellent probe of regions of the AchR structure in contact with the negatively-charged head group of phosphatidylserine. The ‘binding domains’ were localized by chemically cleaving the labeled receptor with cyanogen bromide (CNBr), separating the generated peptides by reverse-phase HPLC, and N-terminal sequence analysis of radiolabeled material. CNBr fragments containing flanking regions of the transmembrane spanning region M4 as well as within M3 were identified within HPLC separated radiolabeled material. The results suggest a topological arrangement of the transmembrane helices in which the hydrophobic faces of M3 and M4 form the boundary of the receptor complex in contact with the lipid bilayer.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
