Caveolin-1 is a major structural protein of caveolae and specifically binds cholesterol (Chol). The caveolin scaffolding domain is thought to be involved in caveolin-Chol interaction through the sequence V94-T-K-Y-W-F-Y-R101, a motif that matches a cholesterol recognition amino-acid consensus (CRAC). In the present work, three CRAC-containing peptides, corresponding to caveolin-1 94-101, 82-101 and 93-126, were tested to study the role of the CRAC motif in the caveolin-Chol interaction in 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) bilayers using differential scanning calorimetry (DSC), fluorescence and circular dichroism (CD). The Y97I substituents of the three peptides and one peptide segment corresponding to caveolin-1 101-126 that excludes the CRAC motif were also tested for comparison. Our results showed the potency of these CRAC-containing peptides in sequestering Chol into domains and the enhanced role of the intramembrane domain and scaffolding domain for the potency. Of the three CRAC-containing peptides, the peptide 93-126 was particularly effective in promoting Chol segregation, while the peptide 82-101 was less potent in promoting the formation of domains than the peptide 93-126, but was more potent than the peptide 94-101. The domain partition of DPPC/Chol bilayers was not observed in the presence of the peptide 101-126, in contrast to the case in the presence of the peptide 93-126 at the same concentrations of peptide and Chol. The potency of the CRAC motif in Chol segregation was lowered by the Y97I mutation. The difference in structure may be a factor that contributes to different effects of these peptides on the distribution of Chol in the lipid membrane.

Tin sulfide (SnS) is attracted much attentions as anode material for sodium ion batteries (SIBs), because of its have various advantages including high capacity and unique 2D structure. However, the...

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A facile hydrothermal method to fabricate Sn/MoS2/C composite as anode material for lithium ion batteries with outstanding performance.

Litchi-like porous Fe/N/C spheres with atomically dispersed FeNx promoted by sulfur are highly efficient electrocatalysts for high-power Zn–air batteries.

A 3D net-like structured fluorescent aerogel as a highly effective adsorbent and sensitive optical sensor of Cr(vi) was fabricated.

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Caveolin-1 is a main structural component of caveolae and essential for the invagination of caveolae by forming a hairpin-shaped structure in the membrane-inserting domain (residues, 102-122). In this article, we determined the tertiary structures of the peptides comprising residues 93-126 and 101-126 of caveolin-1 in 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) aqueous solution and sodium dodecyl sulfate (SDS) micelles, respectively, by nuclear magnetic resonance (NMR) study. The self-association of the peptides in SDS and dodecylphosphocholine (DPC) micelles was also studied by circular dichroism (CD), NMR, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) techniques. Our results indicated that both peptides form a helix-break-helix structure with two helices spanning over Leu103-Phe107 and Ile117-His126 and a loop ranging over Gly108-Gly116. The longer peptide 93-126 showed a stronger propensity to aggregate than the shorter peptide 101-126 in the micelles. Our results suggested that the glycine residues at positions 108 and 116 are important for the break of the helical structure of the membrane-inserting domain and the segment Thr93-Arg101 flanking the membrane-inserting domain may play a role in the self-association of the caveolin-1 protein at cellular membrane.