1GEA

RECEPTOR-BOUND CONFORMATION OF PACAP21

Summary for 1GEA

• Entry DOI: 10.2210/pdb1gea/pdb
• NMR Information: BMRB: 4916
• Descriptor: PITUITARY ADENYLATE CYCLASE ACTIVATING POLYPEPTIDE (1 entity in total)
• Functional Keywords: beta coil, consecutive beta turns, type-ii beta turn, type-i beta turn, helix, neuropeptide
• Total number of polymer chains: 1
• Total formula weight: 2522.88

Authors

Inooka, H.,Ohtaki, T.,Kitahara, O.,Ikegami, T.,Endo, S.,Kitada, C.,Ogi, K.,Onda, H.,Fujino, M.,Shirakawa, M. (deposition date: 2000-10-20, release date: 2001-04-20, Last modification date: 2023-12-27)

Primary citation

Inooka, H.,Ohtaki, T.,Kitahara, O.,Ikegami, T.,Endo, S.,Kitada, C.,Ogi, K.,Onda, H.,Fujino, M.,Shirakawa, M.
Conformation of a peptide ligand bound to its G-protein coupled receptor.
Nat.Struct.Biol., 8:161-165, 2001

PubMed Abstract: Many peptide hormones elicit a wide array of physiological effects by binding to G-protein coupled receptors. We have determined the conformation of pituitary adenylate cyclase activating polypeptide, PACAP(1--21)NH(2), bound to a PACAP-specific receptor by NMR spectroscopy. Residues 3--7 form a unique beta-coil structure that is preceded by an N-terminal extended tail. This beta-coil creates a patch of hydrophobic residues that is important for receptor binding. In contrast, the C-terminal region (residues 8--21) forms an alpha-helix, similar to that in the micelle-bound PACAP. Thus, the conformational difference between PACAP in the receptor-bound and the micelle-bound states is limited to the N-terminal seven residues. This observation is consistent with the two-step ligand transportation model in which PACAP first binds to the membrane nonspecifically and then diffuses two-dimensionally in search of its receptor; a conformational change at the N-terminal region then allows specific interactions between the ligand and the receptor.

PubMed: 11175907
DOI: 10.1038/84159

Experimental method

SOLUTION NMR