1
|
Yoo SH, Buratto J, Roy A, Morvan E, Pasco M, Pulka-Ziach K, Lombardo CM, Rosu F, Gabelica V, Mackereth CD, Collie GW, Guichard G. Adaptive Binding of Alkyl Glycosides by Nonpeptidic Helix Bundles in Water: Toward Artificial Glycolipid Binding Proteins. J Am Chem Soc 2022; 144:15988-15998. [PMID: 35998571 DOI: 10.1021/jacs.2c05234] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Amphipathic water-soluble helices formed from synthetic peptides or foldamers are promising building blocks for the creation of self-assembled architectures with non-natural shapes and functions. While rationally designed artificial quaternary structures such as helix bundles have been shown to contain preformed cavities suitable for guest binding, there are no examples of adaptive binding of guest molecules by such assemblies in aqueous conditions. We have previously reported a foldamer 6-helix bundle that contains an internal nonpolar cavity able to bind primary alcohols as guest molecules. Here, we show that this 6-helix bundle can also interact with larger, more complex guests such as n-alkyl glycosides. X-ray diffraction analysis of co-crystals using a diverse set of guests together with solution and gas-phase studies reveals an adaptive binding mode whereby the apo form of the 6-helix bundle undergoes substantial conformational change to accommodate the hydrocarbon chain in a manner reminiscent of glycolipid transfer proteins in which the cavity forms upon lipid uptake. The dynamic nature of the self-assembling and molecular recognition processes reported here marks a step forward in the design of functional proteomimetic molecular assemblies.
Collapse
Affiliation(s)
- Sung Hyun Yoo
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR5248, IECB, 2 rue Robert Escarpit, F-33600 Pessac, France
| | - Jérémie Buratto
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR5248, IECB, 2 rue Robert Escarpit, F-33600 Pessac, France
| | - Arup Roy
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR5248, IECB, 2 rue Robert Escarpit, F-33600 Pessac, France
| | - Estelle Morvan
- Univ. Bordeaux, CNRS, INSERM, IECB, UAR3033, US001, F-33600 Pessac, France
| | - Morgane Pasco
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR5248, IECB, 2 rue Robert Escarpit, F-33600 Pessac, France
| | | | - Caterina M Lombardo
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR5248, IECB, 2 rue Robert Escarpit, F-33600 Pessac, France
| | - Frédéric Rosu
- Univ. Bordeaux, CNRS, INSERM, IECB, UAR3033, US001, F-33600 Pessac, France
| | - Valérie Gabelica
- Univ. Bordeaux, CNRS, INSERM, IECB, UAR3033, US001, F-33600 Pessac, France.,Univ. Bordeaux, CNRS, INSERM, ARNA, UMR5320, U1212, IECB, F-33600 Bordeaux, France
| | - Cameron D Mackereth
- Univ. Bordeaux, CNRS, INSERM, ARNA, UMR5320, U1212, IECB, F-33600 Bordeaux, France
| | - Gavin W Collie
- Discovery Sciences, R&D, AstraZeneca, Cambridge CB4 0WG, U.K
| | - Gilles Guichard
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR5248, IECB, 2 rue Robert Escarpit, F-33600 Pessac, France
| |
Collapse
|
2
|
Gao YG, McDonald J, Malinina L, Patel DJ, Brown RE. Ceramide-1-phosphate transfer protein promotes sphingolipid reorientation needed for binding during membrane interaction. J Lipid Res 2022; 63:100151. [PMID: 34808193 PMCID: PMC8953657 DOI: 10.1016/j.jlr.2021.100151] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 11/15/2021] [Accepted: 11/16/2021] [Indexed: 12/16/2022] Open
Abstract
Lipid transfer proteins acquire and release their lipid cargoes by interacting transiently with source and destination biomembranes. In the GlycoLipid Transfer Protein (GLTP) superfamily, the two-layer all-α-helical GLTP-fold defines proteins that specifically target sphingolipids (SLs) containing either sugar or phosphate headgroups via their conserved but evolutionarily-modified SL recognitions centers. Despite comprehensive structural insights provided by X-ray crystallography, the conformational dynamics associated with membrane interaction and SL uptake/release by GLTP superfamily members have remained unknown. Herein, we report insights gained from molecular dynamics (MD) simulations into the conformational dynamics that enable ceramide-1-phosphate transfer proteins (CPTPs) to acquire and deliver ceramide-1-phosphate (C1P) during interaction with 1-palmitoyl-2-oleoyl phosphatidylcholine bilayers. The focus on CPTP reflects this protein's involvement in regulating pro-inflammatory eicosanoid production and autophagy-dependent inflammasome assembly that drives interleukin (IL-1β and IL-18) production and release by surveillance cells. We found that membrane penetration by CPTP involved α-6 helix and the α-2 helix N-terminal region, was confined to one bilayer leaflet, and was relatively shallow. Large-scale dynamic conformational changes were minimal for CPTP during membrane interaction or C1P uptake except for the α-3/α-4 helices connecting loop, which is located near the membrane interface and interacts with certain phosphoinositide headgroups. Apart from functioning as a shallow membrane-docking element, α-6 helix was found to adeptly reorient membrane lipids to help guide C1P hydrocarbon chain insertion into the interior hydrophobic pocket of the SL binding site.These findings support a proposed 'hydrocarbon chain-first' mechanism for C1P uptake, in contrast to the 'lipid polar headgroup-first' uptake used by most lipid-transfer proteins.
Collapse
Affiliation(s)
- Yong-Guang Gao
- Hormel Institute, University of Minnesota, Austin, MN, USA.
| | | | - Lucy Malinina
- Hormel Institute, University of Minnesota, Austin, MN, USA
| | - Dinshaw J Patel
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | | |
Collapse
|
3
|
Girr P, Paulsen H. How water-soluble chlorophyll protein extracts chlorophyll from membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1863:183479. [PMID: 32961122 DOI: 10.1016/j.bbamem.2020.183479] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 08/25/2020] [Accepted: 09/15/2020] [Indexed: 10/23/2022]
Abstract
Water-soluble chlorophyll proteins (WSCPs) found in Brassicaceae are non-photosynthetic proteins that bind only a small number of chlorophylls. Their biological function remains unclear, but recent data indicate that WSCPs are involved in stress response and pathogen defense as producers of reactive oxygen species and/or Chl-regulated protease inhibitors. For those functions, WSCP apoprotein supposedly binds Chl to become physiologically active or inactive, respectively. Thus, Chl-binding seems to be a pivotal step for the biological function of WSCP. WSCP can extract Chl from the thylakoid membrane but little is known about the mechanism of how Chl is sequestered from the membrane into the binding sites. Here, we investigate the interaction of WSCP with the thylakoid membrane in detail. The extraction of Chl from the thylakoid by WSCP apoprotein is a slow and inefficient reaction, because WSCP presumably does not directly extract Chl from other Chl-binding proteins embedded in the membrane. WSCP apoprotein interacts with model membranes that contain the thylakoid lipids MGDG, DGDG or PG, and can extract Chl from those. Furthermore, the WSCP-Chl complex, once formed, no longer interacts with membranes. We concluded that the surroundings of the WSCP pigment-binding site are involved in the WSCP-membrane interaction and identified a ring of hydrophobic amino acids with two conserved Trp residues around the Chl-binding site. Indeed, WSCP variants, in which one of the Trp residues was exchanged for Phe, still interact with the membrane but are no longer able to extract Chl.
Collapse
Affiliation(s)
- Philipp Girr
- Institute of Molecular Physiology, Johannes-Gutenberg University Mainz, Johannes-von-Müller-Weg 6, 55128 Mainz, Germany
| | - Harald Paulsen
- Institute of Molecular Physiology, Johannes-Gutenberg University Mainz, Johannes-von-Müller-Weg 6, 55128 Mainz, Germany.
| |
Collapse
|
4
|
Mishra SK, Gao YG, Zou X, Stephenson DJ, Malinina L, Hinchcliffe EH, Chalfant CE, Brown RE. Emerging roles for human glycolipid transfer protein superfamily members in the regulation of autophagy, inflammation, and cell death. Prog Lipid Res 2020; 78:101031. [PMID: 32339554 DOI: 10.1016/j.plipres.2020.101031] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 02/27/2020] [Accepted: 02/27/2020] [Indexed: 12/14/2022]
Abstract
Glycolipid transfer proteins (GLTPs) were first identified over three decades ago as ~24kDa, soluble, amphitropic proteins that specifically accelerate the intermembrane transfer of glycolipids. Upon discovery that GLTPs use a unique, all-α-helical, two-layer 'sandwich' architecture (GLTP-fold) to bind glycosphingolipids (GSLs), a new protein superfamily was born. Structure/function studies have provided exquisite insights defining features responsible for lipid headgroup selectivity and hydrophobic 'pocket' adaptability for accommodating hydrocarbon chains of differing length and unsaturation. In humans, evolutionarily-modified GLTP-folds have been identified with altered sphingolipid specificity, e. g. ceramide-1-phosphate transfer protein (CPTP), phosphatidylinositol 4-phosphate adaptor protein-2 (FAPP2) which harbors a GLTP-domain and GLTPD2. Despite the wealth of structural data (>40 Protein Data Bank deposits), insights into the in vivo functional roles of GLTP superfamily members have emerged slowly. In this review, recent advances are presented and discussed implicating human GLTP superfamily members as important regulators of: i) pro-inflammatory eicosanoid production associated with Group-IV cytoplasmic phospholipase A2; ii) autophagy and inflammasome assembly that drive surveillance cell release of interleukin-1β and interleukin-18 inflammatory cytokines; iii) cell cycle arrest and necroptosis induction in certain colon cancer cell lines. The effects exerted by GLTP superfamily members appear linked to their ability to regulate sphingolipid homeostasis by acting in either transporter and/or sensor capacities. These timely findings are opening new avenues for future cross-disciplinary, translational medical research involving GLTP-fold proteins in human health and disease. Such avenues include targeted regulation of specific GLTP superfamily members to alter sphingolipid levels as a therapeutic means for combating viral infection, neurodegenerative conditions and circumventing chemo-resistance during cancer treatment.
Collapse
Affiliation(s)
- Shrawan K Mishra
- Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | - Yong-Guang Gao
- Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | - Xianqiong Zou
- Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | - Daniel J Stephenson
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University Medical Center, Richmond, VA 23298-0614, USA; Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL 33620, USA
| | - Lucy Malinina
- Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | | | - Charles E Chalfant
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL 33620, USA; Research Service, James A. Haley Veterans Hospital, Tampa, FL 33612, USA; The Moffitt Cancer Center, Tampa, FL 33620, USA
| | | |
Collapse
|
5
|
Zhang X, Huang N, Mo L, Lv M, Gao Y, Wang J, Liu C, Yin S, Zhou J, Xiao N, Pan C, Xu Y, Dong G, Yang Z, Li A, Huang J, Wang Y, Yao Y. Global Transcriptome and Co-Expression Network Analysis Reveal Contrasting Response of Japonica and Indica Rice Cultivar to γ Radiation. Int J Mol Sci 2019; 20:ijms20184358. [PMID: 31491955 PMCID: PMC6769861 DOI: 10.3390/ijms20184358] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 09/01/2019] [Accepted: 09/03/2019] [Indexed: 02/02/2023] Open
Abstract
Japonica and indica are two important subspecies in cultivated Asian rice. Irradiation is a classical approach to induce mutations and create novel germplasm. However, little is known about the differential response between japonica and indica rice after γ radiation. Here, we utilized the RNA sequencing and Weighted Gene Co-expression Network Analysis (WGCNA) to compare the transcriptome differences between japonica Nipponbare (NPB) and indica Yangdao6 (YD6) in response to irradiation. Japonica subspecies are more sensitive to irradiation than the indica subspecies. Indica showed a higher seedling survival rate than japonica. Irradiation caused more extensive DNA damage in shoots than in roots, and the severity was higher in NPB than in YD6. GO and KEGG pathway analyses indicate that the core genes related to DNA repair and replication and cell proliferation are similarly regulated between the varieties, however the universal stress responsive genes show contrasting differential response patterns in japonica and indica. WGCNA identifies 37 co-expressing gene modules and ten candidate hub genes for each module. This provides novel evidence indicating that certain peripheral pathways may dominate the molecular networks in irradiation survival and suggests more potential target genes in breeding for universal stress tolerance in rice.
Collapse
Affiliation(s)
- Xiaoxiang Zhang
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
- Lixiahe Agricultural Research Institute of Jiangsu Province, Yangzhou 225007, China
| | - Niansheng Huang
- Lixiahe Agricultural Research Institute of Jiangsu Province, Yangzhou 225007, China
| | - Lanjing Mo
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Minjia Lv
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Yingbo Gao
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Junpeng Wang
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Chang Liu
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Shuangyi Yin
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Juan Zhou
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Ning Xiao
- Lixiahe Agricultural Research Institute of Jiangsu Province, Yangzhou 225007, China
| | - Cunhong Pan
- Lixiahe Agricultural Research Institute of Jiangsu Province, Yangzhou 225007, China
| | - Yabin Xu
- Yangzhou Irradiation Center, Yangzhou 225007, China
| | - Guichun Dong
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Zefeng Yang
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Aihong Li
- Lixiahe Agricultural Research Institute of Jiangsu Province, Yangzhou 225007, China
| | - Jianye Huang
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
| | - Yulong Wang
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China.
| | - Youli Yao
- Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China.
| |
Collapse
|
6
|
Samaha D, Hamdo HH, Wilde M, Prause K, Arenz C. Sphingolipid-Transporting Proteins as Cancer Therapeutic Targets. Int J Mol Sci 2019; 20:ijms20143554. [PMID: 31330821 PMCID: PMC6678544 DOI: 10.3390/ijms20143554] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 07/16/2019] [Accepted: 07/18/2019] [Indexed: 01/11/2023] Open
Abstract
The understanding of the role of sphingolipid metabolism in cancer has tremendously increased in the past ten years. Many tumors are characterized by imbalances in sphingolipid metabolism. In many cases, disorders of sphingolipid metabolism are also likely to cause or at least promote cancer. In this review, sphingolipid transport proteins and the processes catalyzed by them are regarded as essential components of sphingolipid metabolism. There is much to suggest that these processes are often rate-limiting steps for metabolism of individual sphingolipid species and thus represent potential target structures for pharmaceutical anticancer research. Here, we summarize empirical and biochemical data on different proteins with key roles in sphingolipid transport and their potential role in cancer.
Collapse
Affiliation(s)
- Doaa Samaha
- Institute of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
- Depatment of Pharmaceutical Chemistry, College of Pharmacy, Helwan University, Cairo 11795, Egypt
| | - Housam H Hamdo
- Institute of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
| | - Max Wilde
- Institute of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
| | - Kevin Prause
- Institute of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany
| | - Christoph Arenz
- Institute of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Strasse 2, 12489 Berlin, Germany.
| |
Collapse
|
7
|
In Vitro Measurement of Sphingolipid Intermembrane Transport Illustrated by GLTP Superfamily Members. Methods Mol Biol 2019; 1949:237-256. [PMID: 30790260 DOI: 10.1007/978-1-4939-9136-5_17] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Herein, we describe methodological approaches for measuring in vitro transfer of sphingolipids (SLs) between membranes. The approaches rely on direct tracking of the lipid. Typically, direct tracking involves lipid labeling via attachment of fluorophores or introduction of radioactivity. Members of the GlycoLipid Transfer Protein (GLTP) superfamily are used to illustrate two broadly applicable methods for direct lipid tracking. One method relies on Förster resonance energy transfer (FRET) that enables continuous assessment of fluorophore-labeled SL transfer in real time between lipid donor and acceptor vesicles. The second method relies on tracking of radiolabeled SL transfer by separation of lipid donor and acceptor vesicles at discrete time points. The assays are readily adjustable for assessing lipid transfer (1) between various model membrane assemblies (vesicles, micelles, bicelles, nanodiscs), (2) involving other lipid types by other lipid transfer proteins, (3) with protein preparations that are either crudely or highly purified, and (4) that is spontaneous and occurs in the absence of protein.
Collapse
|
8
|
Glucosylceramide acyl chain length is sensed by the glycolipid transfer protein. PLoS One 2018; 13:e0209230. [PMID: 30550553 PMCID: PMC6294359 DOI: 10.1371/journal.pone.0209230] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 11/30/2018] [Indexed: 12/02/2022] Open
Abstract
The glycolipid transfer protein, GLTP, can be found in the cytoplasm, and it has a FFAT-like motif (two phenylalanines in an acidic tract) that targets it to the endoplasmic reticulum (ER). We have previously shown that GLTP can bind to a transmembrane ER protein, vesicle-associated membrane protein-associated protein A (VAP-A), which is involved in a wide range of ER functions. We have addressed the mechanisms that might regulate the association between GLTP and the VAP proteins by studying the capacity of GLTP to recognize different N-linked acyl chain species of glucosylceramide. We used surface plasmon resonance and a lipid transfer competition assay to show that GLTP prefers shorter N-linked fully saturated acyl chain glucosylceramides, such as C8, C12, and C16, whereas long C18, C20, and C24-glucosylceramides are all bound more weakly and transported more slowly than their shorter counterparts. Changes in the intrinsic GLTP tryptophan fluorescence blueshifts, also indicate a break-point between C16- and C18-glucosylceramide in the GLTP sensing ability. It has long been postulated that GLTP would be a sensor in the sphingolipid synthesis machinery, but how this mechanistically occurs has not been addressed before. It is unclear what proteins the GLTP VAP association would influence. Here we found that if GLTP has a bound GlcCer the association with VAP-A is weaker. We have also used a formula for identifying putative FFAT-domains, and we identified several potential VAP-interactors within the ceramide and sphingolipid synthesis pathways that could be candidates for regulation by GLTP.
Collapse
|
9
|
Domain swapping between FabGs deciphers the structural determinant for in-solution oligomerization and substrate binding. Biophys Chem 2018; 237:9-21. [PMID: 29625337 DOI: 10.1016/j.bpc.2018.03.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 03/15/2018] [Accepted: 03/19/2018] [Indexed: 01/02/2023]
|
10
|
Functional evaluation of tryptophans in glycolipid binding and membrane interaction by HET-C2, a fungal glycolipid transfer protein. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1069-1076. [PMID: 29305831 DOI: 10.1016/j.bbamem.2018.01.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2017] [Revised: 12/16/2017] [Accepted: 01/01/2018] [Indexed: 02/07/2023]
Abstract
HET-C2 is a fungal glycolipid transfer protein (GLTP) that uses an evolutionarily-modified GLTP-fold to achieve more focused transfer specificity for simple neutral glycosphingolipids than mammalian GLTPs. Only one of HET-C2's two Trp residues is topologically identical to the three Trp residues of mammalian GLTP. Here, we provide the first assessment of the functional roles of HET-C2 Trp residues in glycolipid binding and membrane interaction. Point mutants HET-C2W208F, HET-C2W208A and HET-C2F149Y all retained >90% activity and 80-90% intrinsic Trp fluorescence intensity; whereas HET-C2F149A transfer activity decreased to ~55% but displayed ~120% intrinsic Trp emission intensity. Thus, neither W208 nor F149 is absolutely essential for activity and most Trp emission intensity (~85-90%) originates from Trp109. This conclusion was supported by HET-C2W109Y/F149Y which displayed ~8% intrinsic Trp intensity and was nearly inactive. Incubation of the HET-C2 mutants with 1-palmitoyl-2-oleoyl-phosphatidylcholine vesicles containing different monoglycosylceramides or presented by lipid ethanol-injection decreased Trp fluorescence intensity and blue-shifted the Trp λmax by differing amounts compared to wtHET-C2. With HET-C2 mutants for Trp208, the emission intensity decreases (~30-40%) and λmax blue-shifts (~12nm) were more dramatic than for wtHET-C2 or F149 mutants and closely resembled human GLTP. When Trp109 was mutated, the glycolipid induced changes in HET-C2 emission intensity and λmax blue-shift were nearly nonexistent. Our findings indicate that the HET-C2 Trp λmax blue-shift is diagnostic for glycolipid binding; whereas the emission intensity decrease reflects higher environmental polarity encountered upon nonspecific interaction with phosphocholine headgroups comprising the membrane interface and specific interaction with the hydrated glycolipid sugar.
Collapse
|
11
|
Malinina L, Patel DJ, Brown RE. How α-Helical Motifs Form Functionally Diverse Lipid-Binding Compartments. Annu Rev Biochem 2017; 86:609-636. [PMID: 28375742 DOI: 10.1146/annurev-biochem-061516-044445] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Lipids are produced site-specifically in cells and then distributed nonrandomly among membranes via vesicular and nonvesicular trafficking mechanisms. The latter involves soluble amphitropic proteins extracting specific lipids from source membranes to function as molecular solubilizers that envelope their insoluble cargo before transporting it to destination sites. Lipid-binding and lipid transfer structural motifs range from multi-β-strand barrels, to β-sheet cups and baskets covered by α-helical lids, to multi-α-helical bundles and layers. Here, we focus on how α-helical proteins use amphipathic helical layering and bundling to form modular lipid-binding compartments and discuss the functional consequences. Preformed compartments generally rely on intramolecular disulfide bridging to maintain conformation (e.g., albumins, nonspecific lipid transfer proteins, saposins, nematode polyprotein allergens/antigens). Insights into nonpreformed hydrophobic compartments that expand and adapt to accommodate a lipid occupant are few and provided mostly by the three-layer, α-helical ligand-binding domain of nuclear receptors. The simple but elegant and nearly ubiquitous two-layer, α-helical glycolipid transfer protein (GLTP)-fold now further advances understanding.
Collapse
Affiliation(s)
- Lucy Malinina
- The Hormel Institute, University of Minnesota, Austin, Minnesota 55912; ,
| | - Dinshaw J Patel
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065;
| | - Rhoderick E Brown
- The Hormel Institute, University of Minnesota, Austin, Minnesota 55912; ,
| |
Collapse
|
12
|
Zhai X, Gao YG, Mishra SK, Simanshu DK, Boldyrev IA, Benson LM, Bergen HR, Malinina L, Mundy J, Molotkovsky JG, Patel DJ, Brown RE. Phosphatidylserine Stimulates Ceramide 1-Phosphate (C1P) Intermembrane Transfer by C1P Transfer Proteins. J Biol Chem 2016; 292:2531-2541. [PMID: 28011644 DOI: 10.1074/jbc.m116.760256] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 12/21/2016] [Indexed: 11/06/2022] Open
Abstract
Genetic models for studying localized cell suicide that halt the spread of pathogen infection and immune response activation in plants include Arabidopsis accelerated-cell-death 11 mutant (acd11). In this mutant, sphingolipid homeostasis is disrupted via depletion of ACD11, a lipid transfer protein that is specific for ceramide 1-phosphate (C1P) and phyto-C1P. The C1P binding site in ACD11 and in human ceramide-1-phosphate transfer protein (CPTP) is surrounded by cationic residues. Here, we investigated the functional regulation of ACD11 and CPTP by anionic phosphoglycerides and found that 1-palmitoyl-2-oleoyl-phosphatidic acid or 1-palmitoyl-2-oleoyl-phosphatidylglycerol (≤15 mol %) in C1P source vesicles depressed C1P intermembrane transfer. By contrast, replacement with 1-palmitoyl-2-oleoyl-phosphatidylserine stimulated C1P transfer by ACD11 and CPTP. Notably, "soluble" phosphatidylserine (dihexanoyl-phosphatidylserine) failed to stimulate C1P transfer. Also, none of the anionic phosphoglycerides affected transfer action by human glycolipid lipid transfer protein (GLTP), which is glycolipid-specific and has few cationic residues near its glycolipid binding site. These findings provide the first evidence for a potential phosphoglyceride headgroup-specific regulatory interaction site(s) existing on the surface of any GLTP-fold and delineate new differences between GLTP superfamily members that are specific for C1P versus glycolipid.
Collapse
Affiliation(s)
- Xiuhong Zhai
- From the Hormel Institute, University of Minnesota, Austin, Minnesota 55912,
| | - Yong-Guang Gao
- From the Hormel Institute, University of Minnesota, Austin, Minnesota 55912
| | - Shrawan K Mishra
- From the Hormel Institute, University of Minnesota, Austin, Minnesota 55912
| | - Dhirendra K Simanshu
- the Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065
| | - Ivan A Boldyrev
- the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia
| | - Linda M Benson
- the Medical Genomic Facility-Proteomics Core, Mayo Foundation, Rochester, Minnesota 55905, and
| | - H Robert Bergen
- the Medical Genomic Facility-Proteomics Core, Mayo Foundation, Rochester, Minnesota 55905, and
| | - Lucy Malinina
- From the Hormel Institute, University of Minnesota, Austin, Minnesota 55912
| | - John Mundy
- the Department of Biology, BioCenter, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Julian G Molotkovsky
- the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia
| | - Dinshaw J Patel
- the Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065
| | - Rhoderick E Brown
- From the Hormel Institute, University of Minnesota, Austin, Minnesota 55912,
| |
Collapse
|
13
|
Rao E, Singh P, Zhai X, Li Y, Zhu G, Zhang Y, Hao J, Chi YI, Brown RE, Cleary MP, Li B. Inhibition of tumor growth by a newly-identified activator for epidermal fatty acid binding protein. Oncotarget 2016; 6:7815-27. [PMID: 25796556 PMCID: PMC4480718 DOI: 10.18632/oncotarget.3485] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 02/04/2015] [Indexed: 11/25/2022] Open
Abstract
Our previous studies have demonstrated that expression of epidermal fatty acid binding protein (E-FABP) in tumor associated macrophages (TAMs) promotes macrophage anti-tumor activity by enhancing IFNβ responses in tumor models. Thus, E-FABP represents a new protective factor in enhancing tumor immune surveillance against tumor development. Herein, we report the compound 5-(benzylamino)-2-(3-methylphenyl)-1,3-oxazole-4-carbonitrile (designated EI-05) as a novel E-FABP activator for inhibition of mammary tumor growth. EI-05 was selected from the ZINC compound library using molecular docking analysis based on the crystal structure of E-FABP. Although EI-05 is unable to bind E-FABP directly, it significantly increases E-FABP expression in macrophages during inflammation. Stimulation of macrophages with EI-05 remarkably enhances lipid droplet formation and IFNβ production, which further promotes the anti-tumor activity of macrophages. Importantly, administering EI-05 in vivo significantly inhibits mammary tumor growth in a syngeneic mouse model. Altogether, these results suggest that EI-05 may represent a promising drug candidate for anti-tumor treatment through enhancing E-FABP activity and IFNβ responses in macrophages.
Collapse
Affiliation(s)
- Enyu Rao
- The Hormel Institute, University of Minnesota, Austin, MN, USA
| | - Puja Singh
- The Hormel Institute, University of Minnesota, Austin, MN, USA
| | - Xiuhong Zhai
- The Hormel Institute, University of Minnesota, Austin, MN, USA
| | - Yan Li
- The Hormel Institute, University of Minnesota, Austin, MN, USA
| | - Ganqian Zhu
- The Hormel Institute, University of Minnesota, Austin, MN, USA
| | - Yuwen Zhang
- The Hormel Institute, University of Minnesota, Austin, MN, USA
| | - Jiaqing Hao
- The Hormel Institute, University of Minnesota, Austin, MN, USA
| | - Young-In Chi
- The Hormel Institute, University of Minnesota, Austin, MN, USA
| | | | - Margot P Cleary
- The Hormel Institute, University of Minnesota, Austin, MN, USA
| | - Bing Li
- The Hormel Institute, University of Minnesota, Austin, MN, USA
| |
Collapse
|
14
|
Mattjus P. Specificity of the mammalian glycolipid transfer proteins. Chem Phys Lipids 2016; 194:72-8. [DOI: 10.1016/j.chemphyslip.2015.07.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2015] [Revised: 07/08/2015] [Accepted: 07/27/2015] [Indexed: 12/31/2022]
|
15
|
Malinina L, Simanshu DK, Zhai X, Samygina VR, Kamlekar R, Kenoth R, Ochoa-Lizarralde B, Malakhova ML, Molotkovsky JG, Patel DJ, Brown RE. Sphingolipid transfer proteins defined by the GLTP-fold. Q Rev Biophys 2015; 48:281-322. [PMID: 25797198 PMCID: PMC4691851 DOI: 10.1017/s003358351400016x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Glycolipid transfer proteins (GLTPs) originally were identified as small (~24 kDa), soluble, amphitropic proteins that specifically accelerate the intermembrane transfer of glycolipids. GLTPs and related homologs now are known to adopt a unique, helically dominated, two-layer 'sandwich' architecture defined as the GLTP-fold that provides the structural underpinning for the eukaryotic GLTP superfamily. Recent advances now provide exquisite insights into structural features responsible for lipid headgroup selectivity as well as the adaptability of the hydrophobic compartment for accommodating hydrocarbon chains of differing length and unsaturation. A new understanding of the structural versatility and evolutionary premium placed on the GLTP motif has emerged. Human GLTP-motifs have evolved to function not only as glucosylceramide binding/transferring domains for phosphoinositol 4-phosphate adaptor protein-2 during glycosphingolipid biosynthesis but also as selective binding/transfer proteins for ceramide-1-phosphate. The latter, known as ceramide-1-phosphate transfer protein, recently has been shown to form GLTP-fold while critically regulating Group-IV cytoplasmic phospholipase A2 activity and pro-inflammatory eicosanoid production.
Collapse
Affiliation(s)
- Lucy Malinina
- The Hormel Institute, University of Minnesota, Austin, MN 55912, USA
- Structural Biology Unit, CICbioGUNE, Technology Park of Bizkaia, 48160 Derio-Bilbao, Spain
| | - Dhirendra K. Simanshu
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA
| | - Xiuhong Zhai
- The Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | - Valeria R. Samygina
- Structural Biology Unit, CICbioGUNE, Technology Park of Bizkaia, 48160 Derio-Bilbao, Spain
| | | | - Roopa Kenoth
- The Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | - Borja Ochoa-Lizarralde
- Structural Biology Unit, CICbioGUNE, Technology Park of Bizkaia, 48160 Derio-Bilbao, Spain
| | | | - Julian G. Molotkovsky
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Dinshaw J. Patel
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA
| | | |
Collapse
|
16
|
Simanshu DK, Zhai X, Munch D, Hofius D, Markham JE, Bielawski J, Bielawska A, Malinina L, Molotkovsky JG, Mundy JW, Patel DJ, Brown RE. Arabidopsis accelerated cell death 11, ACD11, is a ceramide-1-phosphate transfer protein and intermediary regulator of phytoceramide levels. Cell Rep 2014; 6:388-99. [PMID: 24412362 PMCID: PMC3931444 DOI: 10.1016/j.celrep.2013.12.023] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Revised: 10/21/2013] [Accepted: 12/12/2013] [Indexed: 12/11/2022] Open
Abstract
The accelerated cell death 11 (acd11) mutant of Arabidopsis provides a genetic model for studying immune response activation and localized cellular suicide that halt pathogen spread during infection in plants. Here, we elucidate ACD11 structure and function and show that acd11 disruption dramatically alters the in vivo balance of sphingolipid mediators that regulate eukaryotic-programmed cell death. In acd11 mutants, normally low ceramide-1-phosphate (C1P) levels become elevated, but the relatively abundant cell death inducer phytoceramide rises acutely. ACD11 exhibits selective intermembrane transfer of C1P and phyto-C1P. Crystal structures establish C1P binding via a surface-localized, phosphate headgroup recognition center connected to an interior hydrophobic pocket that adaptively ensheaths lipid chains via a cleft-like gating mechanism. Point mutation mapping confirms functional involvement of binding site residues. A π helix (π bulge) near the lipid binding cleft distinguishes apo-ACD11 from other GLTP folds. The global two-layer, α-helically dominated, "sandwich" topology displaying C1P-selective binding identifies ACD11 as the plant prototype of a GLTP fold subfamily.
Collapse
Affiliation(s)
- Dhirendra K Simanshu
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA
| | - Xiuhong Zhai
- Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | - David Munch
- Department of Biology, BioCenter, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Daniel Hofius
- Department of Biology, BioCenter, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Jennifer E Markham
- Department of Biochemistry, University of Nebraska, N146 Beadle Center, Lincoln, NE 68588, USA
| | - Jacek Bielawski
- Department of Biochemistry and Molecular Biology, Lipidomics Shared Resource Mass Spectrometry Lab, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Alicja Bielawska
- Department of Biochemistry and Molecular Biology, Lipidomics Shared Resource Mass Spectrometry Lab, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Lucy Malinina
- Structural Biology Unit, CIC bioGUNE, Technology Park of Bizkaia, 48160 Derio-Bilbao, Spain
| | - Julian G Molotkovsky
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia
| | - John W Mundy
- Department of Biology, BioCenter, University of Copenhagen, 2200 Copenhagen N, Denmark.
| | - Dinshaw J Patel
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA.
| | | |
Collapse
|
17
|
Tuuf J, Mattjus P. Membranes and mammalian glycolipid transferring proteins. Chem Phys Lipids 2013; 178:27-37. [PMID: 24220498 DOI: 10.1016/j.chemphyslip.2013.10.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Revised: 10/29/2013] [Accepted: 10/30/2013] [Indexed: 01/04/2023]
Abstract
Glycolipids are synthesized in and on various organelles throughout the cell. Their trafficking inside the cell is complex and involves both vesicular and protein-mediated machineries. Most important for the bulk lipid transport is the vesicular system, however, lipids moved by transfer proteins are also becoming more characterized. Here we review the latest advances in the glycolipid transfer protein (GLTP) and the phosphoinositol 4-phosphate adaptor protein-2 (FAPP2) field, from a membrane point of view.
Collapse
Affiliation(s)
- Jessica Tuuf
- Biochemistry, Department of Biosciences, Åbo Akademi University, Turku, Finland
| | - Peter Mattjus
- Biochemistry, Department of Biosciences, Åbo Akademi University, Turku, Finland.
| |
Collapse
|
18
|
D’Angelo G, Uemura T, Chuang CC, Polishchuk E, Santoro M, Ohvo-Rekilä H, Sato T, Di Tullio G, Varriale A, D’Auria S, Daniele T, Capuani F, Johannes L, Mattjus P, Monti M, Pucci P, Williams RL, Burke JE, Platt FM, Harada A, De Matteis MA. Vesicular and non-vesicular transport feed distinct glycosylation pathways in the Golgi. Nature 2013; 501:116-20. [DOI: 10.1038/nature12423] [Citation(s) in RCA: 289] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Accepted: 06/25/2013] [Indexed: 11/09/2022]
|
19
|
Samygina VR, Ochoa-Lizarralde B, Popov AN, Cabo-Bilbao A, Goni-de-Cerio F, Molotkovsky JG, Patel DJ, Brown RE, Malinina L. Structural insights into lipid-dependent reversible dimerization of human GLTP. ACTA CRYSTALLOGRAPHICA. SECTION D, BIOLOGICAL CRYSTALLOGRAPHY 2013; 69:603-16. [PMID: 23519669 PMCID: PMC3606038 DOI: 10.1107/s0907444913000024] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Accepted: 01/01/2013] [Indexed: 11/10/2022]
Abstract
Human glycolipid transfer protein (hsGLTP) forms the prototypical GLTP fold and is characterized by a broad transfer selectivity for glycosphingolipids (GSLs). The GLTP mutation D48V near the `portal entrance' of the glycolipid binding site has recently been shown to enhance selectivity for sulfatides (SFs) containing a long acyl chain. Here, nine novel crystal structures of hsGLTP and the SF-selective mutant complexed with short-acyl-chain monoSF and diSF in different crystal forms are reported in order to elucidate the potential functional roles of lipid-mediated homodimerization. In all crystal forms, the hsGLTP-SF complexes displayed homodimeric structures supported by similarly organized intermolecular interactions. The dimerization interface always involved the lipid sphingosine chain, the protein C-terminus (C-end) and α-helices 6 and 2, but the D48V mutant displayed a `locked' dimer conformation compared with the hinge-like flexibility of wild-type dimers. Differences in contact angles, areas and residues at the dimer interfaces in the `flexible' and `locked' dimers revealed a potentially important role of the dimeric structure in the C-end conformation of hsGLTP and in the precise positioning of the key residue of the glycolipid recognition centre, His140. ΔY207 and ΔC-end deletion mutants, in which the C-end is shifted or truncated, showed an almost complete loss of transfer activity. The new structural insights suggest that ligand-dependent reversible dimerization plays a role in the function of human GLTP.
Collapse
Affiliation(s)
- Valeria R. Samygina
- Structural Biology Unit, CIC bioGUNE, Technology Park of Bizkaia, 48160 Derio, Spain
| | | | | | - Aintzane Cabo-Bilbao
- Structural Biology Unit, CIC bioGUNE, Technology Park of Bizkaia, 48160 Derio, Spain
| | - Felipe Goni-de-Cerio
- Structural Biology Unit, CIC bioGUNE, Technology Park of Bizkaia, 48160 Derio, Spain
| | - Julian G. Molotkovsky
- Shemyakin–Ovchinnikov Institute of Bioorganic Chemistry, RAS, Moscow 117997, Russian Federation
| | - Dinshaw J. Patel
- Structural Biology Program, Memorial Sloan–Kettering Cancer Center, New York, NY 10021, USA
| | | | - Lucy Malinina
- Structural Biology Unit, CIC bioGUNE, Technology Park of Bizkaia, 48160 Derio, Spain
| |
Collapse
|
20
|
Lauria I, van Üüm J, Mjumjunov-Crncevic E, Walrafen D, Spitta L, Thiele C, Lang T. GLTP mediated non-vesicular GM1 transport between native membranes. PLoS One 2013; 8:e59871. [PMID: 23555818 PMCID: PMC3610762 DOI: 10.1371/journal.pone.0059871] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Accepted: 02/19/2013] [Indexed: 11/24/2022] Open
Abstract
Lipid transfer proteins (LTPs) are emerging as key players in lipid homeostasis by mediating non-vesicular transport steps between two membrane surfaces. Little is known about the driving force that governs the direction of transport in cells. Using the soluble LTP glycolipid transfer protein (GLTP), we examined GM1 (monosialotetrahexosyl-ganglioside) transfer to native membrane surfaces. With artificial GM1 donor liposomes, GLTP can be used to increase glycolipid levels over natural levels in either side of the membrane leaflet, i.e., external or cytosolic. In a system with native donor- and acceptor-membranes, we find that GLTP balances highly variable GM1 concentrations in a population of membranes from one cell type, and in addition, transfers lipids between membranes from different cell types. Glycolipid transport is highly efficient, independent of cofactors, solely driven by the chemical potential of GM1 and not discriminating between the extra- and intracellular membrane leaflet. We conclude that GLTP mediated non-vesicular lipid trafficking between native membranes is driven by simple thermodynamic principles and that for intracellular transport less than 1 µM GLTP would be required in the cytosol. Furthermore, the data demonstrates the suitability of GLTP as a tool for artificially increasing glycolipid levels in cellular membranes.
Collapse
Affiliation(s)
- Ines Lauria
- Department of Membrane Biochemistry, LIMES (Life and Medical Sciences) Institute, University of Bonn, Bonn, Germany
| | - Jan van Üüm
- Department of Membrane Biochemistry, LIMES (Life and Medical Sciences) Institute, University of Bonn, Bonn, Germany
| | - Esmina Mjumjunov-Crncevic
- Department of Membrane Biochemistry, LIMES (Life and Medical Sciences) Institute, University of Bonn, Bonn, Germany
| | - David Walrafen
- Department of Membrane Biochemistry, LIMES (Life and Medical Sciences) Institute, University of Bonn, Bonn, Germany
| | - Luis Spitta
- Department of Membrane Biochemistry, LIMES (Life and Medical Sciences) Institute, University of Bonn, Bonn, Germany
| | - Christoph Thiele
- Department of Biochemistry and Cell Biology of Lipids, LIMES Institute, University of Bonn, Bonn, Germany
| | - Thorsten Lang
- Department of Membrane Biochemistry, LIMES (Life and Medical Sciences) Institute, University of Bonn, Bonn, Germany
- * E-mail:
| |
Collapse
|
21
|
The glycolipid transfer protein (GLTP) domain of phosphoinositol 4-phosphate adaptor protein-2 (FAPP2): structure drives preference for simple neutral glycosphingolipids. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1831:417-27. [PMID: 23159414 DOI: 10.1016/j.bbalip.2012.10.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Revised: 10/23/2012] [Accepted: 10/29/2012] [Indexed: 11/23/2022]
Abstract
Phosphoinositol 4-phosphate adaptor protein-2 (FAPP2) plays a key role in glycosphingolipid (GSL) production using its C-terminal domain to transport newly synthesized glucosylceramide away from the cytosol-facing glucosylceramide synthase in the cis-Golgi for further anabolic processing. Structural homology modeling against human glycolipid transfer protein (GLTP) predicts a GLTP-fold for FAPP2 C-terminal domain, but no experimental support exists to warrant inclusion in the GLTP superfamily. Here, the biophysical properties and glycolipid transfer specificity of FAPP2-C-terminal domain have been characterized and compared with other established GLTP-folds. Experimental evidence for a GLTP-fold includes: i) far-UV circular dichroism (CD) showing secondary structure with high alpha-helix content and a low thermally-induced unfolding transition (~41°C); ii) near-UV-CD indicating only subtle tertiary conformational change before/after interaction with membranes containing/lacking glycolipid; iii) Red-shifted tryptophan (Trp) emission wavelength maximum (λ(max)~352nm) for apo-FAPP2-C-terminal domain consistent with surface exposed intrinsic Trp residues; iv) 'signature' GLTP-fold Trp fluorescence response, i.e., intensity decrease (~30%) accompanied by strongly blue-shifted λ(max) (~14nm) upon interaction with membranes containing glycolipid, supporting direct involvement of Trp in glycolipid binding and enabling estimation of partitioning affinities. A structurally-based preference for other simple uncharged GSLs, in addition to glucosylceramide, makes human FAPP2-GLTP more similar to fungal HET-C2 than to plant AtGLTP1 (glucosylceramide-specific) or to broadly GSL-selective human GLTP. These findings along with the distinct mRNA exon/intron organizations originating from single-copy genes on separate human chromosomes suggest adaptive evolutionary divergence by these two GLTP-folds.
Collapse
|
22
|
Halin J, Mattjus P. Effects of bile salts on glucosylceramide containing membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1808:2886-93. [DOI: 10.1016/j.bbamem.2011.08.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Revised: 08/15/2011] [Accepted: 08/25/2011] [Indexed: 01/17/2023]
|
23
|
Kenoth R, Kamlekar RK, Simanshu DK, Gao Y, Malinina L, Prendergast FG, Molotkovsky JG, Patel DJ, Venyaminov SY, Brown RE. Conformational folding and stability of the HET-C2 glycolipid transfer protein fold: does a molten globule-like state regulate activity? Biochemistry 2011; 50:5163-71. [PMID: 21553912 DOI: 10.1021/bi200382c] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The glycolipid transfer protein (GLTP) superfamily is defined by the human GLTP fold that represents a novel motif for lipid binding and transfer and for reversible interaction with membranes, i.e., peripheral amphitropic proteins. Despite limited sequence homology with human GLTP, we recently showed that HET-C2 GLTP of Podospora anserina is organized conformationally as a GLTP fold. Currently, insights into the folding stability and conformational states that regulate GLTP fold activity are almost nonexistent. To gain such insights into the disulfide-less GLTP fold, we investigated the effect of a change in pH on the fungal HET-C2 GLTP fold by taking advantage of its two tryptophans and four tyrosines (compared to three tryptophans and 10 tyrosines in human GLTP). pH-induced conformational alterations were determined by changes in (i) intrinsic tryptophan fluorescence (intensity, emission wavelength maximum, and anisotropy), (ii) circular dichroism over the near-UV and far-UV ranges, including thermal stability profiles of the derivatized molar ellipticity at 222 nm, (iii) fluorescence properties of 1-anilinonaphthalene-8-sulfonic acid, and (iv) glycolipid intermembrane transfer activity monitored by Förster resonance energy transfer. Analyses of our recently determined crystallographic structure of HET-C2 (1.9 Å) allowed identification of side chain electrostatic interactions that contribute to HET-C2 GLTP fold stability and can be altered by a change in pH. Side chain interactions include numerous salt bridges and interchain cation-π interactions, but not intramolecular disulfide bridges. Histidine residues are especially important for stabilizing the local positioning of the two tryptophan residues and the conformation of adjacent chains. Induction of a low-pH-induced, molten globule-like state inhibited glycolipid intermembrane transfer by the HET-C2 GLTP fold.
Collapse
Affiliation(s)
- Roopa Kenoth
- The Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Monitoring glycolipid transfer protein activity and membrane interaction with the surface plasmon resonance technique. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1808:47-54. [DOI: 10.1016/j.bbamem.2010.08.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2010] [Revised: 08/17/2010] [Accepted: 08/24/2010] [Indexed: 01/23/2023]
|
25
|
Carton I, Lucy Malinina, Richter RP. Dynamic modulation of the glycosphingolipid content in supported lipid bilayers by glycolipid transfer protein. Biophys J 2010; 99:2947-56. [PMID: 21044592 PMCID: PMC2966009 DOI: 10.1016/j.bpj.2010.09.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2010] [Revised: 09/05/2010] [Accepted: 09/08/2010] [Indexed: 11/17/2022] Open
Abstract
Supported lipid bilayers (SLBs) are popular models of cell membranes. Owing to the importance of glycosphingolipids (GSLs) in modulating structure and function of membranes and membrane proteins, methods to tune the GSL content in SLBs would be desirable. Glycolipid transfer protein (GLTP) can selectively transfer GSLs between membrane compartments. Using the ganglioside GM1 as a model GSL, and two mass-sensitive and label-free characterization techniques-quartz crystal microbalance with dissipation monitoring and ellipsometry-we demonstrate that GLTP is an efficient and robust biochemical tool to dynamically modulate the GSL content of SLBs up to 10 mol % GM1, and to quantitatively control the GSL content in the bulk-facing SLB leaflet. By exploiting what we believe to be a novel tool, we provide evidence that GM1 distributes highly asymmetrically in silica-supported lipid bilayers, with ∼85% of the ganglioside being present in the bulk-facing membrane leaflet. We report also that the pentameric B-subunit of cholera toxin binds with close-to-maximal stoichiometry to GM1 in SLBs over a large range of GM1 concentrations. Furthermore, we quantify the liganding affinity of GLTP for GM1 in an SLB context to be 1.5 μM.
Collapse
Affiliation(s)
- Ixaskun Carton
- Biosurfaces Unit, Cooperative Research Center in Biomaterials (CIC biomaGUNE), San Sebastian, Spain
| | - Lucy Malinina
- Structural Biology Unit, Cooperative Research Center in Biosciences (CIC bioGUNE), Derio, Spain
| | - Ralf P. Richter
- Biosurfaces Unit, Cooperative Research Center in Biomaterials (CIC biomaGUNE), San Sebastian, Spain
- Max-Planck-Institute for Metals Research, Stuttgart, Germany
| |
Collapse
|
26
|
Kamlekar RK, Gao Y, Kenoth R, Molotkovsky JG, Prendergast FG, Malinina L, Patel DJ, Wessels WS, Venyaminov SY, Brown RE. Human GLTP: Three distinct functions for the three tryptophans in a novel peripheral amphitropic fold. Biophys J 2010; 99:2626-35. [PMID: 20959104 PMCID: PMC2955354 DOI: 10.1016/j.bpj.2010.08.038] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2010] [Revised: 07/27/2010] [Accepted: 08/10/2010] [Indexed: 01/17/2023] Open
Abstract
Human glycolipid transfer protein (GLTP) serves as the GLTP-fold prototype, a novel, to our knowledge, peripheral amphitropic fold and structurally unique lipid binding motif that defines the GLTP superfamily. Despite conservation of all three intrinsic Trps in vertebrate GLTPs, the Trp functional role(s) remains unclear. Herein, the issue is addressed using circular dichroism and fluorescence spectroscopy along with an atypical Trp point mutation strategy. Far-ultraviolet and near-ultraviolet circular dichroism spectroscopic analyses showed that W96F-W142Y-GLTP and W96Y-GLTP retain their native conformation and stability, whereas W85Y-W96F-GLTP is slightly altered, in agreement with relative glycolipid transfer activities of >90%, ∼85%, and ∼45%, respectively. In silico three-dimensional modeling and acrylamide quenching of Trp fluorescence supported a nativelike folding conformation. With the Trp⁹⁶-less mutants, changes in emission intensity, wavelength maximum, lifetime, and time-resolved anisotropy decay induced by phosphoglyceride membranes lacking or containing glycolipid and by excitation at different wavelengths along the absorption-spectrum red edge indicated differing functions for W142 and W85. The data suggest that W142 acts as a shallow-penetration anchor during docking with membrane interfaces, whereas the buried W85 indole helps maintain proper folding and possibly regulates membrane-induced transitioning to a glycolipid-acquiring conformation. The findings illustrate remarkable versatility for Trp, providing three distinct intramolecular functions in the novel amphitropic GLTP fold.
Collapse
Affiliation(s)
| | - Yongguang Gao
- The Hormel Institute, University of Minnesota, Austin, Minnesota
| | - Roopa Kenoth
- The Hormel Institute, University of Minnesota, Austin, Minnesota
| | - Julian G. Molotkovsky
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | | | - Lucy Malinina
- Structural Biology, Centro de Investigación Cooperativa BioGUNE, Derio, Spain
| | - Dinshaw J. Patel
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York
| | | | | | | |
Collapse
|
27
|
Kenoth R, Simanshu DK, Kamlekar RK, Pike HM, Molotkovsky JG, Benson LM, Bergen HR, Prendergast FG, Malinina L, Venyaminov SY, Patel DJ, Brown RE. Structural determination and tryptophan fluorescence of heterokaryon incompatibility C2 protein (HET-C2), a fungal glycolipid transfer protein (GLTP), provide novel insights into glycolipid specificity and membrane interaction by the GLTP fold. J Biol Chem 2010; 285:13066-78. [PMID: 20164530 DOI: 10.1074/jbc.m109.093203] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
HET-C2 is a fungal protein that transfers glycosphingolipids between membranes and has limited sequence homology with human glycolipid transfer protein (GLTP). The human GLTP fold is unique among lipid binding/transfer proteins, defining the GLTP superfamily. Herein, GLTP fold formation by HET-C2, its glycolipid transfer specificity, and the functional role(s) of its two Trp residues have been investigated. X-ray diffraction (1.9 A) revealed a GLTP fold with all key sugar headgroup recognition residues (Asp(66), Asn(70), Lys(73), Trp(109), and His(147)) conserved and properly oriented for glycolipid binding. Far-UV CD showed secondary structure dominated by alpha-helices and a cooperative thermal unfolding transition of 49 degrees C, features consistent with a GLTP fold. Environmentally induced optical activity of Trp/Tyr/Phe (2:4:12) detected by near-UV CD was unaffected by membranes containing glycolipid but was slightly altered by membranes lacking glycolipid. Trp fluorescence was maximal at approximately 355 nm and accessible to aqueous quenchers, indicating free exposure to the aqueous milieu and consistent with surface localization of the two Trps. Interaction with membranes lacking glycolipid triggered significant decreases in Trp emission intensity but lesser than decreases induced by membranes containing glycolipid. Binding of glycolipid (confirmed by electrospray injection mass spectrometry) resulted in a blue-shifted emission wavelength maximum (approximately 6 nm) permitting determination of binding affinities. The unique positioning of Trp(208) at the HET-C2 C terminus revealed membrane-induced conformational changes that precede glycolipid uptake, whereas key differences in residues of the sugar headgroup recognition center accounted for altered glycolipid specificity and suggested evolutionary adaptation for the simpler glycosphingolipid compositions of filamentous fungi.
Collapse
Affiliation(s)
- Roopa Kenoth
- Hormel Institute, University of Minnesota, Austin, Minnesota 55912, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Severino V, Chambery A, Di Maro A, Marasco D, Ruggiero A, Berisio R, Giansanti F, Ippoliti R, Parente A. The role of the glycan moiety on the structure–function relationships of PD-L1, type 1 ribosome-inactivating protein from P. dioica leaves. MOLECULAR BIOSYSTEMS 2010; 6:570-9. [DOI: 10.1039/b919801f] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|