Caveolin-1 endows order in cholesterol-rich detergent resistant membranes

Research output: Contribution to journalArticlepeer-review

Abstract

Cholesterol-enriched functional portions of plasma membranes, such as caveolae and rafts, were isolated from lungs of wild-type (WT) and caveolin-1 knockout (Cav-1 KO) mice within detergent resistant membranes (DRMs). To gain insight into their molecular composition we performed proteomic and lipid analysis on WT and Cav-1 KO-DRMs that showed predicted variations of proteomic profiles and negligible differences in lipid composition, while Langmuir monolayer technique and small and wide-angle X-ray scattering (SAXS-WAXS) were here originally introduced to study DRMs biophysical association state. Langmuir analysis of Cav-1 containing DRMs displayed an isotherm with a clear-cut feature, suggesting the coexistence of the liquid-ordered (Lo) phase typical of the raft structure, namely “cholesterol-rich Lo phase,” with a phase fully missing in Cav-1 KO that we named “caveolin-induced Lo phase.” Furthermore, while the sole lipid component of both WT and KO-DRMs showed qualitatively similar isotherm configuration, the reinsertion of recombinant Cav-1 into WT-DRMs lipids restored the WT-DRM pattern. X-ray diffraction results confirmed that Cav-1 causes the formation of a “caveolin-induced Lo phase,” as suggested by Langmuir experiments, allowing us to speculate about a possible structural model. These results show that the unique molecular link between Cav-1 and cholesterol can spur functional order in a lipid bilayer strictly derived from biological sources.

Original languageEnglish
Article number287
JournalBiomolecules
Volume9
Issue number7
DOIs
Publication statusPublished - Jul 2019

Keywords

  • Caveolae
  • Cholesterol-rich microdomains
  • Langmuir films
  • Lipid rafts
  • Liquid order
  • Membrane heterogeneity
  • Membranes/fluidity
  • Membranes/model lipid-rafts
  • Membranes/physical chemistry

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology

Fingerprint

Dive into the research topics of 'Caveolin-1 endows order in cholesterol-rich detergent resistant membranes'. Together they form a unique fingerprint.

Cite this