Structure and orientation of sarcolipin in lipid environments

Alessandro Mascioni, Christine B Karim, George Barany, David D Thomas, Gianluigi Veglia

Research output: Contribution to journalArticlepeer-review

70 Scopus citations

Abstract

Sarcolipin (SLN) is a 31 amino acid integral membrane protein that regulates Ca-ATPase activity in skeletal muscle. Here, we report the three-dimensional structure and topology of synthetic SLN in lipid environments, as determined by solution and solid-state NMR spectroscopy. 2D solution NMR experiments were performed on SLN solubilized in sodium dodecyl sulfate (SDS) micelles. We found that SLN adopts a highly defined α-helical conformation from F9 through R27, with a backbone RMSD of 0.65 Å and a side chain RMSD of 1.66 Å. The N-terminus (M1 through L8) and the C-terminus (S28 through Y31) are mostly unstructured. The orientation of the SLN was determined using one-dimensional 15N NMR solid-state spectroscopy. The protein was incorporated into phospholipid bilayers prepared from a mixture of 1,2-dioleoyl-sn-glycero-3-phosphocholine and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine. The 15N chemical shift solid-state spectra from selectively labeled SLN samples indicate that SLN orients perpendicularly to the plane of the membrane bilayers. These results support the proposed mechanism of Ca-ATPase regulation of SLN via protein-protein intramembranous interactions between the highly conserved transmembrane domains of the Ca-ATPase and the conserved transmembrane domain of SLN.

Original languageEnglish (US)
Pages (from-to)475-482
Number of pages8
JournalBiochemistry
Volume41
Issue number2
DOIs
StatePublished - Jan 15 2002

Fingerprint Dive into the research topics of 'Structure and orientation of sarcolipin in lipid environments'. Together they form a unique fingerprint.

Cite this