Investigating the conformational coupling between the transmembrane and cytoplasmic domains of a single-spanning membrane protein. A 1H-NMR study.

Florence Mousson (1) , Veronica Beswick (1) , Yves-Marie Coïc (2) , Tam Huynh-Dinh (2) , Alain Sanson (1) , Jean-Michel Neumann (1)

1 Service de Biophysique des Fonctions Membranaires
2 Chimie Organique

PMP1 is a 38-residue single-spanning membrane protein whose C-terminal cytoplasmic domain, Y25-F38, is highly positively charged. The conformational coupling between the transmembrane span and the cytoplasmic domain of PMP1 was investigated from 1H-nuclear magnetic resonance data of two synthetic fragments: F9-F38, i.e. 80% of the whole sequence, and Y25-F38, the isolated cytoplasmic domain. Highly disordered in aqueous solution, the Y25-F38 peptide adopts a well-defined conformation in the presence of dodecylphosphocholine micelles. Compared with the long PMP1 fragment, this structure exhibits both native and non-native elements. Our results make it possible to assess the influence of a hydrophobic anchor on the intrinsic conformational propensity of a cytoplasmic domain.

Domains: Life Sciences [q-bio]

Florence Mousson, Veronica Beswick, Yves-Marie Coïc, Tam Huynh-Dinh, Alain Sanson, et al.. Investigating the conformational coupling between the transmembrane and cytoplasmic domains of a single-spanning membrane protein. A 1H-NMR study.. FEBS Letters, 2001, 505 (3), pp.431-5. ⟨10.1016/S0014-5793(01)02864-2⟩. ⟨pasteur-00166884⟩