Contributions of the interdomain loop, amino terminus, and subunit interface to the ligand-facilitated dimerization of neurophysin: crystal structures and mutation studies of bovine neurophysin-I.

ABSTRACT: Current evidence indicates that the ligand-facilitated dimerization of neurophysin is mediated in part by dimerization-induced changes at the hormone binding site of the unliganded state that increase ligand affinity. To elucidate other contributory factors, we investigated the potential role of neurophysin's short interdomain loop (residues 55-59), particularly the effects of loop residue mutation and of deleting amino-terminal residues 1-6, which interact with the loop and adjacent residues 53-54. The neurophysin studied was bovine neurophysin-I, necessitating determination of the crystal structures of des 1-6 bovine neurophysin-I in unliganded and liganded dimeric states, as well as the structure of its liganded Q58V mutant, in which peptide was bound with unexpectedly increased affinit

SUBMITTER: Li X 

PROVIDER: S-EPMC2222833 | biostudies-literature | 2007 Jan

REPOSITORIES: biostudies-literature