Comparison of fragments comprising the first two helices of the human Y4 and the yeast Ste2p G-protein-coupled receptors.

ABSTRACT: Solution NMR techniques are used to determine the structure and the topology of micelle integration of a large fragment of the Y4 receptor, a human G-protein-coupled receptor, that contains the entire N-terminal domain plus the first two transmembrane (TM) segments. The structure calculations reveal that the putative TM helices are indeed helical to a large extent, but that interruptions of secondary structure occur close to internal polar or charged residues. This view is supported by (15)N relaxation data, amide-water exchange rates, and attenuations from micelle-integrating spin labels. No contacts between different helices are observed. This is in contrast to a similar TM1-TM2 fragment from the yeast Ste2p receptor for which locations of the secondary and the tertiary structure agreed

SUBMITTER: Shao X 

PROVIDER: S-EPMC3443771 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature