These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Cysteine residues in the carboxyl terminal domain of the endothelin-B receptor are required for coupling with G-proteins.
    Author: Okamoto Y, Ninomiya H, Tanioka M, Sakamoto A, Miwa S, Masaki T.
    Journal: J Cardiovasc Pharmacol; 1998; 31 Suppl 1():S230-2. PubMed ID: 9595445.
    Abstract:
    We demonstrate that the human endothelin-B (ETB) receptor incorporates [3H]palmitic acid. Mutation of three putative palmitoylated cysteine residues (amino acids 402, 403 and 405) in the carboxyl terminus into serine residues (C2/3/5S) completely prevented palmitoylation of ETB. When expressed in CHO cells, C2/3/5S was localized on the cell surface, retained high affinity for ET-1 and ET-3, and was rapidly internalized when bound to the ligand. However, unlike the wild-type ETB, C2/3/5S transmitted neither an inhibitory effect on adenylate cyclase nor a stimulatory effect on phospholipase C, indicating a critical role of palmitoylation in the coupling with G-proteins, regardless of the G-protein subtype. Truncation of the carboxyl terminus, including all or a part of the three cysteine residues, gave palmitoylation-negative and -positive deletion mutants, delta 402 and delta 403. Despite the absence of the cytoplasmic tail, both delta 402 and delta 403 showed essentially the same features as C2/3/5S, except that delta 403 did transmit a stimulatory effect on phospholipase C via a pertussis toxin-insensitive G-protein, most likely a member(s) of the Gq family. These results indicated a differential requirement for the carboxyl terminus downstream from the palmitoylation site in the coupling with G-protein subtypes, i.e., it is required for the coupling with Gi but not for that with Gq.
    [Abstract] [Full Text] [Related] [New Search]