Caveolin-1 and cavin1 act synergistically to generate a unique lipid environment in caveolae

Caveolae are specialized domains of the vertebrate cell surface with a well-defined morphology and crucial roles in cell migration and mechanoprotection. Unique compositions of proteins and lipids determine membrane architectures. The precise caveolar lipid profile and the roles of the major caveolar structural proteins, caveolins and cavins, in selectively sorting lipids have not been defined. Here, we used quantitative nanoscale lipid mapping together with molecular dynamic simulations to define the caveolar lipid profile. We show that caveolin-1 (CAV1) and cavin1 individually sort distinct plasma membrane lipids. Intact caveolar structures composed of both CAV1 and cavin1 further generate a unique lipid nano-environment. The caveolar lipid sorting capability includes selectivities for lipid headgroups and acyl chains. Because lipid headgroup metabolism and acyl chain remodeling are tightly regulated, this selective lipid sorting may allow caveolae to act as transit hubs to direct communications among lipid metabolism, vesicular trafficking, and signaling.

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Dissecting the nanoscale lipid profile of caveolae

10.1101/2020.01.16.909408 ◽

2020 ◽

Author(s):

Yong Zhou ◽

Nicholas Ariotti ◽

James Rae ◽

Hong Liang ◽

Vikas Tillu ◽

...

Keyword(s):

Lipid Profile ◽

Membrane Lipids ◽

Acyl Chain ◽

Vesicular Trafficking ◽

Structural Proteins ◽

Dynamic Simulations ◽

Vertebrate Cell ◽

Lipid Sorting ◽

Acyl Chains ◽

Direct Communications

AbstractCaveolae are specialized domains of the vertebrate cell surface with a well-defined morphology and crucial roles in cell migration and mechanoprotection. Unique compositions of proteins and lipids determine membrane architectures. The precise caveolar lipid profile and the roles of the major caveolar structural proteins, caveolins and cavins, in selectively sorting lipids have not been defined. Here we used quantitative nanoscale lipid mapping together with molecular dynamic simulations to define the caveolar lipid profile. We show that caveolin1 (CAV1) and cavin1 individually sort distinct plasma membrane lipids. Intact caveolar structures composed of both CAV1 and cavin1 further generate a unique lipid nano-environment. The caveolar lipid sorting capability includes selectivities for lipid headgroups and acyl chains. Because lipid headgroup metabolism and acyl chain remodelling are tightly regulated, this selective lipid sorting may allow caveolae to act as transit hubs to direct communications among lipid metabolism, vesicular trafficking and signalling.

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Structural basis for acyl chain control over glycosphingolipid sorting and vesicular trafficking

10.1101/2021.04.26.440603 ◽

2021 ◽

Author(s):

Stefanie S. Schmieder ◽

Raju Tatituri ◽

Michael Anderson ◽

Kate Kelly ◽

Wayne I. Lencer

Keyword(s):

Acyl Chain ◽

Vesicular Trafficking ◽

Structural Motif ◽

Structural Basis ◽

Membrane Organization ◽

Endosomal Sorting ◽

Lysosomal Sorting ◽

Acyl Chains ◽

Complex Sphingolipids ◽

Endocytic Pathways

AbstractThe complex sphingolipids exhibit a diversity of ceramide acyl chain structures that influence their trafficking and intracellular distributions, but how the cell discerns among the different ceramides to affect such sorting remains unknown. To address mechanism, we synthesized a library of GM1 glycosphingolipids with naturally varied acyl chains and quantitatively assessed their sorting among different endocytic pathways. We found that a stretch of at least 14 saturated carbons extending from C1 at the water-bilayer interface dictated lysosomal sorting by exclusion from endosome sorting tubules. Sorting to the lysosome by the C14*-motif was cholesterol dependent. Perturbations of the C14*-motif by unsaturation enabled GM1 entry into endosomal sorting tubules of the recycling and retrograde pathways independently of cholesterol. Unsaturation occurring beyond the C14*-motif in very long acyl chains rescued lysosomal sorting. These results define a structural motif underlying membrane organization of sphingolipids and implicate cholesterol-sphingolipid nanodomain formation in sorting mechanisms.

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Saturated very long chain fatty acid configures glycosphingolipid for lysosome homeostasis in long-lived C. elegans

Nature Communications ◽

10.1038/s41467-021-25398-6 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Feng Wang ◽

Yuxi Dai ◽

Xufeng Zhu ◽

Qilong Chen ◽

Huanhu Zhu ◽

...

Keyword(s):

Fatty Acid ◽

Membrane Lipids ◽

Acyl Chain ◽

Behenic Acid ◽

Long Chain Fatty Acid ◽

Fatty Acid Elongase ◽

C Elegans ◽

Acyl Chains ◽

Membrane Budding ◽

Lifespan Regulation

AbstractThe contents of numerous membrane lipids change upon ageing. However, it is unknown whether and how any of these changes are causally linked to lifespan regulation. Acyl chains contribute to the functional specificity of membrane lipids. In this study, working with C. elegans, we identified an acyl chain-specific sphingolipid, C22 glucosylceramide, as a longevity metabolite. Germline deficiency, a conserved lifespan-extending paradigm, induces somatic expression of the fatty acid elongase ELO-3, and behenic acid (22:0) generated by ELO-3 is incorporated into glucosylceramide for lifespan regulation. Mechanistically, C22 glucosylceramide is required for the membrane localization of clathrin, a protein that regulates membrane budding. The reduction in C22 glucosylceramide impairs the clathrin-dependent autophagic lysosome reformation, which subsequently leads to TOR activation and longevity suppression. These findings reveal a mechanistic link between membrane lipids and ageing and suggest a model of lifespan regulation by fatty acid-mediated membrane configuration.

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Characterization of the Lipidome and Biophysical Properties of Membranes from High Five Insect Cells Expressing Mouse P-Glycoprotein

10.20944/preprints202102.0204.v1 ◽

2021 ◽

Author(s):

Maria João Moreno ◽

Patrícia Alexandra Teles Martins ◽

Eva Bernardino ◽

Biebele Abel ◽

Suresh Ambudkar

Keyword(s):

Insect Cells ◽

Acyl Chain ◽

Model Membranes ◽

Protein Ratio ◽

P Glycoprotein ◽

Phospholipid Classes ◽

Representative Model ◽

Acyl Chains ◽

Lipid Environment

The lipid composition of biomembranes influence the properties of the lipid bilayer as well as that of the proteins. In this study, the lipidome and the lipid/protein ratio of membranes from High FiveTM insect cells overexpressing mouse P-glycoprotein was characterized. This provides a better understanding of the lipid environment in which P-glycoprotein is embedded, and thus of its functional and structural properties. The relative abundance of the distinct phospholipid classes and their acyl chain composition was characterized. A mass ratio of 0.57 +/- 0.11 phospholipids to protein was obtained. Phosphatidylethanolamines are the most abundant phospholipids, followed by phosphatidylcholines. Membranes are also enriched in negatively charged lipids (phosphatidylserines, phosphatidylinositols and phosphatidylglycerols), and contain small amounts of sphingomyelins, ceramides and monoglycosilatedceramides. The most abundant acyl chains are monounsaturated, with significant amounts of saturated chains. The characterization of the phospholipids by HPLC-MS allowed identification of the combination of acyl chains, with palmitoyl-oleoyl being the most representative for all major phospholipid classes except for phosphatidylserines, which are mostly saturated. A mixture of POPE:POPC:POPS in the ratio 45:35:20 is proposed for the preparation of simple representative model membranes. The adequacy of the model membranes was further evaluated by characterizing their surface potential and fluidity.

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Characterization of the Lipidome and Biophysical Properties of Membranes from High Five Insect Cells Expressing Mouse P-Glycoprotein

Biomolecules ◽

10.3390/biom11030426 ◽

2021 ◽

Vol 11 (3) ◽

pp. 426

Author(s):

Maria João Moreno ◽

Patrícia Alexandra Teles Martins ◽

Eva F. Bernardino ◽

Biebele Abel ◽

Suresh V. Ambudkar

Keyword(s):

Insect Cells ◽

Acyl Chain ◽

Model Membranes ◽

Protein Ratio ◽

P Glycoprotein ◽

Phospholipid Classes ◽

Representative Model ◽

Acyl Chains ◽

Lipid Environment

The lipid composition of biomembranes influences the properties of the lipid bilayer and that of the proteins. In this study, the lipidome and the lipid/protein ratio of membranes from High Five™ insect cells overexpressing mouse P-glycoprotein was characterized. This provides a better understanding of the lipid environment in which P-glycoprotein is embedded, and thus of its functional and structural properties. The relative abundance of the distinct phospholipid classes and their acyl chain composition was characterized. A mass ratio of 0.57 ± 0.11 phospholipids to protein was obtained. Phosphatidylethanolamines are the most abundant phospholipids, followed by phosphatidylcholines. Membranes are also enriched in negatively charged lipids (phosphatidylserines, phosphatidylinositols and phosphatidylglycerols), and contain small amounts of sphingomyelins, ceramides and monoglycosilatedceramides. The most abundant acyl chains are monounsaturated, with significant amounts of saturated chains. The characterization of the phospholipids by HPLC-MS allowed identification of the combination of acyl chains, with palmitoyl-oleoyl being the most representative for all major phospholipid classes except for phosphatidylserines, which are mostly saturated. A mixture of POPE:POPC:POPS in the ratio 45:35:20 is proposed for the preparation of simple representative model membranes. The adequacy of the model membranes was further evaluated by characterizing their surface potential and fluidity.

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Lipid-dependent Subcellular Relocalization of the Acyl Chain Desaturase in Yeast

Molecular Biology of the Cell ◽

10.1091/mbc.e02-04-0196 ◽

2002 ◽

Vol 13 (12) ◽

pp. 4429-4442 ◽

Cited By ~ 22

Author(s):

Verena Tatzer ◽

Günther Zellnig ◽

Sepp D. Kohlwein ◽

Roger Schneiter

Keyword(s):

Secretory Pathway ◽

Unsaturated Fatty Acids ◽

Membrane Lipids ◽

Acyl Chain ◽

Lipid Synthesis ◽

Mitochondrial Morphology ◽

Temperature Sensitive ◽

Cell Periphery ◽

Critical Determinant ◽

Acyl Chains

The degree of acyl chain desaturation of membrane lipids is a critical determinant of membrane fluidity. Temperature-sensitive mutants of the single essential acyl chain desaturase, Ole1p, of yeast have previously been isolated in screens for mitochondrial inheritance mutants ( Stewart, L.C., and Yaffe, M.P. (1991). J. Cell Biol.115, 1249–1257 ). We now report that the mutant desaturase relocalizes from its uniform ER distribution to a more punctuate localization at the cell periphery upon inactivation of the enzyme. This relocalization takes place within minutes at nonpermissive conditions, a time scale at which mitochondrial morphology and inheritance is not yet affected. Relocalization of the desaturase is fully reversible and does not affect the steady state localization of other ER resident proteins or the kinetic and fidelity of the secretory pathway, indicating a high degree of selectivity for the desaturase. Relocalization of the desaturase is energy independent but is lipid dependent because it is rescued by supplementation with unsaturated fatty acids. Relocalization of the desaturase is also observed in cells treated with inhibitors of the enzyme, indicating that it is independent of temperature-induced alterations of the enzyme. In the absence of desaturase function, lipid synthesis continues, resulting in the generation of lipids with saturated acyl chains. A model is discussed in which the accumulation of saturated lipids in a microdomain around the desaturase could induce the observed segregation and relocalization of the enzyme.

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A mass spectrometric method for in-depth profiling of phosphoinositide regioisomers and their disease-associated regulation

Nature Communications ◽

10.1038/s41467-021-27648-z ◽

2022 ◽

Vol 13 (1) ◽

Author(s):

Shin Morioka ◽

Hiroki Nakanishi ◽

Toshiyoshi Yamamoto ◽

Junya Hasegawa ◽

Emi Tokuda ◽

...

Keyword(s):

Membrane Lipids ◽

Acyl Chain ◽

Depth Profiling ◽

Comprehensive Analysis ◽

Spectrometric Method ◽

Mass Spectrometric Method ◽

Chiral Column ◽

Acyl Chains ◽

Cancer Tissues ◽

Biological State

AbstractPhosphoinositides are a family of membrane lipids essential for many biological and pathological processes. Due to the existence of multiple phosphoinositide regioisomers and their low intracellular concentrations, profiling these lipids and linking a specific acyl variant to a change in biological state have been difficult. To enable the comprehensive analysis of phosphoinositide phosphorylation status and acyl chain identity, we develop PRMC-MS (Phosphoinositide Regioisomer Measurement by Chiral column chromatography and Mass Spectrometry). Using this method, we reveal a severe skewing in acyl chains in phosphoinositides in Pten-deficient prostate cancer tissues, extracellular mobilization of phosphoinositides upon expression of oncogenic PIK3CA, and a unique profile for exosomal phosphoinositides. Thus, our approach allows characterizing the dynamics of phosphoinositide acyl variants in intracellular and extracellular milieus.

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Lipid Profiles of RAS Nanoclusters Regulate RAS Function

Biomolecules ◽

10.3390/biom11101439 ◽

2021 ◽

Vol 11 (10) ◽

pp. 1439

Author(s):

Yong Zhou ◽

John F. Hancock

Keyword(s):

Lipid Composition ◽

Human Cancer ◽

Acyl Chain ◽

Super Resolution ◽

Small Gtpases ◽

Ras Signaling ◽

Structural Components ◽

Dynamic Simulations ◽

Lipid Sorting ◽

Resolution Imaging

The lipid-anchored RAS (Rat sarcoma) small GTPases (guanosine triphosphate hydrolases) are highly prevalent in human cancer. Traditional strategies of targeting the enzymatic activities of RAS have been shown to be difficult. Alternatively, RAS function and pathology are mostly restricted to nanoclusters on the plasma membrane (PM). Lipids are important structural components of these signaling platforms on the PM. However, how RAS nanoclusters selectively enrich distinct lipids in the PM, how different lipids contribute to RAS signaling and oncogenesis and whether the selective lipid sorting of RAS nanoclusters can be targeted have not been well-understood. Latest advances in quantitative super-resolution imaging and molecular dynamic simulations have allowed detailed characterization RAS/lipid interactions. In this review, we discuss the latest findings on the select lipid composition (with headgroup and acyl chain specificities) within RAS nanoclusters, the specific mechanisms for the select lipid sorting of RAS nanoclusters on the PM and how perturbing lipid compositions within RAS nanoclusters impacts RAS function and pathology. We also describe different strategies of manipulating lipid composition within RAS nanoclusters on the PM.

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Integrated lipidomics and proteomics reveal cardiolipin alterations, upregulation of HADHA and long chain fatty acids in pancreatic cancer stem cells

Scientific Reports ◽

10.1038/s41598-021-92752-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Claudia Di Carlo ◽

Bebiana C. Sousa ◽

Marcello Manfredi ◽

Jessica Brandi ◽

Elisa Dalla Pozza ◽

...

Keyword(s):

Pancreatic Cancer ◽

Stem Cells ◽

Fatty Acid ◽

Cancer Stem Cells ◽

Acyl Chain ◽

Fatty Acid Elongase ◽

Acyl Chains ◽

A Chain ◽

Pancreatic Cancer Stem Cells ◽

Long Chain

AbstractPancreatic cancer stem cells (PCSCs) play a key role in the aggressiveness of pancreatic ductal adenocarcinomas (PDAC); however, little is known about their signaling and metabolic pathways. Here we show that PCSCs have specific and common proteome and lipidome modulations. PCSCs displayed downregulation of lactate dehydrogenase A chain, and upregulation of trifunctional enzyme subunit alpha. The upregulated proteins of PCSCs are mainly involved in fatty acid (FA) elongation and biosynthesis of unsaturated FAs. Accordingly, lipidomics reveals an increase in long and very long-chain unsaturated FAs, which are products of fatty acid elongase-5 predicted as a key gene. Moreover, lipidomics showed the induction in PCSCs of molecular species of cardiolipin with mixed incorporation of 16:0, 18:1, and 18:2 acyl chains. Our data indicate a crucial role of FA elongation and alteration in cardiolipin acyl chain composition in PCSCs, representing attractive therapeutic targets in PDAC.

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The Profound Influence of Lipid Composition on the Catalysis of the Drug Target NADH Type II Oxidoreductase

Membranes ◽

10.3390/membranes11050363 ◽

2021 ◽

Vol 11 (5) ◽

pp. 363

Author(s):

Albert Godoy-Hernandez ◽

Duncan G. G. McMillan

Keyword(s):

Acyl Chain ◽

Cellular Respiration ◽

Type Ii ◽

Nadh:Quinone Oxidoreductase ◽

Chain Composition ◽

Membrane Bound ◽

Lipid Environment ◽

Lipid Specificity ◽

Mediated Catalysis ◽

Quinone Pool

Lipids play a pivotal role in cellular respiration, providing the natural environment in which an oxidoreductase interacts with the quinone pool. To date, it is generally accepted that negatively charged lipids play a major role in the activity of quinone oxidoreductases. By changing lipid compositions when assaying a type II NADH:quinone oxidoreductase, we demonstrate that phosphatidylethanolamine has an essential role in substrate binding and catalysis. We also reveal the importance of acyl chain composition, specifically c14:0, on membrane-bound quinone-mediated catalysis. This demonstrates that oxidoreductase lipid specificity is more diverse than originally thought and that the lipid environment plays an important role in the physiological catalysis of membrane-bound oxidoreductases.

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