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Shimasaki K, Okemoto-Nakamura Y, Saito K, Fukasawa M, Katoh K, Hanada K. A high-resolution phase-contrast microscopy system for label-free imaging in living cells. Cell Struct Funct 2024; 49:21-29. [PMID: 38797697 DOI: 10.1247/csf.24018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2024] Open
Abstract
Cell biologists have long sought the ability to observe intracellular structures in living cells without labels. This study presents procedures to adjust a commercially available apodized phase-contrast (APC) microscopy system for better visualizing the dynamic behaviors of various subcellular organelles in living cells. By harnessing the versatility of this technique to capture sequential images, we could observe morphological changes in cellular geometry after virus infection in real time without probes or invasive staining. The tune-up APC microscopy system is a highly efficient platform for simultaneously observing the dynamic behaviors of diverse subcellular structures with exceptional resolution.
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Affiliation(s)
- Kentaro Shimasaki
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases
| | - Yuko Okemoto-Nakamura
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases
| | - Kyoko Saito
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases
| | - Masayoshi Fukasawa
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases
| | - Kaoru Katoh
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST)
- AIRC, National Institute of Advanced Industrial Science and Technology (AIST)
| | - Kentaro Hanada
- Center for Quality Management Systems, National Institute of Infectious Diseases
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Ishii Y, Yamaji T, Sekizuka T, Homma Y, Mori S, Takeuchi T, Kukimoto I. Folliculin Prevents Lysosomal Degradation of Human Papillomavirus To Support Infectious Cell Entry. J Virol 2023; 97:e0005623. [PMID: 37167561 PMCID: PMC10231244 DOI: 10.1128/jvi.00056-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 04/20/2023] [Indexed: 05/13/2023] Open
Abstract
Human papillomavirus (HPV) infects epithelial basal cells in the mucosa and either proliferates with the differentiation of the basal cells or persists in them. Multiple host factors are required to support the HPV life cycle; however, the molecular mechanisms involved in cell entry are not yet fully understood. In this study, we performed a genome-wide clustered regularly interspaced short palindromic repeat (CRISPR)-CRISPR-associated protein 9 (Cas9) knockout (KO) screen in HeLa cells and identified folliculin (FLCN), a GTPase-activating protein for Rag GTPases, as an important host factor for HPV infection. The introduction of single guide RNAs for the FLCN gene into HeLa, HaCaT, and ectocervical Ect1 cells reduced infection by HPV18 pseudovirions (18PsVs) and 16PsVs. FLCN KO HeLa cells also exhibited strong resistance to infection with 18PsVs and 16PsVs; nevertheless, they remained highly susceptible to infections with vesicular stomatitis virus glycoprotein-pseudotyped lentivirus and adeno-associated virus. Immunofluorescence microscopy revealed that the numbers of virions binding to the cell surface were slightly increased in FLCN KO cells. However, virion internalization analysis showed that the internalized virions were rapidly degraded in FLCN KO cells. This degradation was blocked by treatment with the lysosome inhibitor bafilomycin A1. Furthermore, the virion degradation phenotype was also observed in Ras-related GTP-binding protein C (RagC) KO cells. These results suggest that FLCN prevents the lysosomal degradation of incoming HPV virions by enhancing lysosomal RagC activity. IMPORTANCE Cell entry by human papillomavirus (HPV) involves a cellular retrograde transport pathway from the endosome to the trans-Golgi network/Golgi apparatus. However, the mechanism by which this viral trafficking is safeguarded is poorly understood. This is the first study showing that the GTPase-activating protein folliculin (FLCN) protects incoming HPV virions from lysosomal degradation and supports infectious cell entry by activating the Rag GTPases, presumably through the suppression of excessive lysosomal biosynthesis. These findings provide new insights into the effects of small GTPase activity regulation on HPV cell entry and enhance our understanding of the HPV degradation pathway.
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Affiliation(s)
- Yoshiyuki Ishii
- Pathogen Genomics Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Toshiyuki Yamaji
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Tsuyoshi Sekizuka
- Pathogen Genomics Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Yuta Homma
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Seiichiro Mori
- Pathogen Genomics Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Takamasa Takeuchi
- Pathogen Genomics Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Iwao Kukimoto
- Pathogen Genomics Center, National Institute of Infectious Diseases, Tokyo, Japan
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Emecen Sanli M, Kilic A, Inci A, Okur I, Ezgu F, Tumer L. Endocrinological, immunological and metabolic features of patients with Fabry disease under therapy. J Pediatr Endocrinol Metab 2023; 0:jpem-2023-0105. [PMID: 37257483 DOI: 10.1515/jpem-2023-0105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 04/20/2023] [Indexed: 06/02/2023]
Abstract
OBJECTIVES Fabry disease is an X-linked lysosomal disorder caused by decreased or absent alpha galactosidase enzyme. The enzyme deficiency leads to progressive accumulation of globotriaosylceramide (Gb-3) and its deacetylated form lyso-Gb3 in various tissue lysosomes that results in primarily lysosomal deterioration and subsequently mitochondrial, endothelial, and immunologic dysfunctions. METHODS The endocrinological, metabolic, immunological and HLA status of 12 patients were evaluated. RESULTS A total of 11 patients (91.6 %) had immunologic and/or endocrinologic abnormalities. fT4, anti-TPO, and anti-TG levels were increased in 1, 2, and 2 patients, respectively. Three patients had elevated proinflammatory cytokines. ANA profile, p-ANCA and c-ANCA were positive in 1, 1, and 2 patients, respectively. Tissue transglutaminase antibody was negative in all patients however P5 was diagnosed with Celiac disease at the age of 12 and on gluten free diet. All patients had distinct types of HLA apart from 2 patients with anti-TG and anti-TPO positive and there was no relationship between the HLA types and the autoimmunity biomarkers. CONCLUSIONS FD may have impact on endocrinologic and immunologic abnormalities even in the patients under ERT, therefore prevalence of these abnormalities may be higher in ERT naïve patients. However, apparently, they are less likely to cause clinical symptoms. Certain HLA alleles may contribute to the direct impact of immunological pathogenesis in FD by developing abnormal autoimmune biomarkers. To the best of our knowledge, this is the first study investigating HLA status of FD patients; therefore further studies are needed to elucidate the underlying mechanism of action.
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Affiliation(s)
- Merve Emecen Sanli
- Department of Pediatrics, Division of Inborn Errors of Metabolism, Istanbul Basaksehir City Hospital, Gazi University Medical Faculty, Ankara, Türkiye
| | - Ayse Kilic
- Department of Pediatrics, Division of Inborn Errors of Metabolism, Istanbul Basaksehir City Hospital, Gazi University Medical Faculty, Ankara, Türkiye
| | - Asli Inci
- Department of Pediatrics, Division of Inborn Errors of Metabolism, Istanbul Basaksehir City Hospital, Gazi University Medical Faculty, Ankara, Türkiye
| | - Ilyas Okur
- Department of Pediatrics, Division of Inborn Errors of Metabolism, Istanbul Basaksehir City Hospital, Gazi University Medical Faculty, Ankara, Türkiye
| | - Fatih Ezgu
- Department of Pediatrics, Division of Inborn Errors of Metabolism, Istanbul Basaksehir City Hospital, Gazi University Medical Faculty, Ankara, Türkiye
| | - Leyla Tumer
- Department of Pediatrics, Division of Inborn Errors of Metabolism, Istanbul Basaksehir City Hospital, Gazi University Medical Faculty, Ankara, Türkiye
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Goto A, Hanada K. Protocol for casein kinase 1γ3 CSNK1G3 gene knockout and recombinant gene expression in cultured HeLa cells. STAR Protoc 2023; 4:102251. [PMID: 37119140 PMCID: PMC10173854 DOI: 10.1016/j.xpro.2023.102251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 02/23/2023] [Accepted: 03/28/2023] [Indexed: 04/30/2023] Open
Abstract
Casein kinase 1γ is a subfamily of the casein kinase 1 family. Here, we present a protocol for gene knockout of CSNK1G3 in human cells and cloning and/or expression of CSNK1G1-3 cDNAs using a retroviral vector system. We first describe the genome editing procedures, including sgRNA design, introduction into HeLa cells, and verification of genome editing. Next, we describe the procedures for cloning human CSNK1G cDNAs, introduction into HeLa cells, and expression verification by western blot analysis. For complete information on the generation and use of this protocol, please refer to Goto et al.1.
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Affiliation(s)
- Asako Goto
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan; Department of Virology III, National Institute of Infectious Diseases, Musashimurayama City, Tokyo 208-0011, Japan.
| | - Kentaro Hanada
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan; Department of Quality Assurance, Radiation Safety, and Information System, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan
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Yamaji T, Homma Y. Construction of Sphingolipid Remodeled Cells by Genome Editing. Methods Mol Biol 2023; 2613:111-125. [PMID: 36587075 DOI: 10.1007/978-1-0716-2910-9_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Sphingolipids are ubiquitously expressed in eukaryotes and play various functional roles. The key characteristic of sphingolipids is their diversity of molecular species. Sphingomyelin (SM) and glycosphingolipids (GSLs) are the major components of sphingolipids in the plasma membrane, which are composed of ceramide and a polar head-group. SM is the most abundant sphingolipid species in mammalian cells, while GSLs have a wide variety of glycans as head groups. Various fatty acids in ceramide also contribute to the diversity of sphingolipid species. To analyze the cellular function of each sphingolipid species, precise gene manipulation is essential. Recent developments in genome editing technologies have facilitated complete gene disruption in cultured cells. This chapter describes protocols for the construction of various sphingolipid-related gene knockout HeLa cells using the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 system and for confirmation of changes in their lipid composition using radioisotopes and thin layer chromatography. This sphingolipid-remodeled cell panel is a useful tool for analyzing the cellular functions of sphingolipid species and as a reference for lipid analysis.
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Affiliation(s)
- Toshiyuki Yamaji
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Tokyo, Japan.
| | - Yuta Homma
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Tokyo, Japan
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Goto A, Egawa D, Tomishige N, Yamaji T, Shimasaki K, Kumagai K, Hanada K. Involvement of a Cluster of Basic Amino Acids in Phosphorylation-Dependent Functional Repression of the Ceramide Transport Protein CERT. Int J Mol Sci 2022; 23:ijms23158576. [PMID: 35955719 PMCID: PMC9368931 DOI: 10.3390/ijms23158576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Revised: 07/27/2022] [Accepted: 07/29/2022] [Indexed: 12/10/2022] Open
Abstract
Ceramide transport protein (CERT) mediates ceramide transfer from the endoplasmic reticulum to the Golgi for sphingomyelin (SM) biosynthesis. CERT is inactivated by multiple phosphorylation at the serine-repeat motif (SRM), and mutations that impair the SRM phosphorylation are associated with a group of inherited intellectual disorders in humans. It has been suggested that the N-terminal phosphatidylinositol 4-monophosphate [PtdIns(4)P] binding domain and the C-terminal ceramide-transfer domain of CERT physically interfere with each other in the SRM phosphorylated state, thereby repressing the function of CERT; however, it remains unclear which regions in CERT are involved in the SRM phosphorylation-dependent repression of CERT. Here, we identified a previously uncharacterized cluster of lysine/arginine residues that were predicted to be located on the outer surface of a probable coiled-coil fold in CERT. Substitutions of the basic amino acids in the cluster with alanine released the SRM-dependent repression of CERT activities, i.e., the synthesis of SM, PtdIns(4)P-binding, vesicle-associated membrane protein-associated protein (VAP) binding, ceramide-transfer activity, and localization to the Golgi, although the effect on SM synthesis activity was only partially compromised by the alanine substitutions, which moderately destabilized the trimeric status of CERT. These results suggest that the basic amino acid cluster in the coiled-coil region is involved in the regulation of CERT function.
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Affiliation(s)
- Asako Goto
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan; (A.G.); (D.E.); (T.Y.); (K.S.); (K.K.)
| | - Daichi Egawa
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan; (A.G.); (D.E.); (T.Y.); (K.S.); (K.K.)
| | - Nario Tomishige
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan; (A.G.); (D.E.); (T.Y.); (K.S.); (K.K.)
- Correspondence: (N.T.); (K.H.)
| | - Toshiyuki Yamaji
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan; (A.G.); (D.E.); (T.Y.); (K.S.); (K.K.)
| | - Kentaro Shimasaki
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan; (A.G.); (D.E.); (T.Y.); (K.S.); (K.K.)
| | - Keigo Kumagai
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan; (A.G.); (D.E.); (T.Y.); (K.S.); (K.K.)
| | - Kentaro Hanada
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan; (A.G.); (D.E.); (T.Y.); (K.S.); (K.K.)
- Department of Quality Assurance, Radiation Safety, and Information System, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan
- Correspondence: (N.T.); (K.H.)
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Goto A, Sakai S, Mizuike A, Yamaji T, Hanada K. Compartmentalization of casein kinase 1 γ CSNK1G controls the intracellular trafficking of ceramide. iScience 2022; 25:104624. [PMID: 35800758 PMCID: PMC9254030 DOI: 10.1016/j.isci.2022.104624] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 03/20/2022] [Accepted: 06/13/2022] [Indexed: 11/28/2022] Open
Abstract
Casein kinase 1 γ (CK1G) is involved in the regulation of various cellular functions. For instance, the ceramide transport protein (CERT), which delivers ceramide to the Golgi apparatus for the synthesis of sphingomyelin (SM), is inactivated when it receives multiple phosphorylation by CK1G. Using human genome-wide gene disruption screening with an SM-binding cytolysin, we found that loss of the C-terminal region of CK1G3 rendered the kinase hyperactive in cells. Deletion of the C-terminal 20 amino acids or mutation of cysteine residues expected to be palmitoylated sites redistributed CK1G3 from cytoplasmic punctate compartments to the nucleocytoplasm. Wild-type CK1G3 exhibited a similar redistribution in the presence of 2-bromopalmitate, a protein palmitoylation inhibitor. Expression of C-terminal mutated CK1G1/2/3 similarly induced the multiple phosphorylation of the CERT SRM, thereby down-regulating de novo SM synthesis. These findings revealed that CK1Gs are regulated by a compartmentalization-based mechanism to access substrates present in specific intracellular organelles. C-terminal region of CSNK1Gs restricts their localization to punctate compartments Loss of the kinase compartmentalization causes hyperphosphorylation of CERT Compartmentalization of CSNK1G controls ceramide transport and de novo SM synthesis
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Affiliation(s)
- Asako Goto
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Shota Sakai
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Aya Mizuike
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Toshiyuki Yamaji
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Kentaro Hanada
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan
- Corresponding author
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8
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Modulation of Zika virus replication via glycosphingolipids. Virology 2022; 572:17-27. [DOI: 10.1016/j.virol.2022.03.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 03/30/2022] [Accepted: 03/30/2022] [Indexed: 11/18/2022]
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Glycosphingolipids in human embryonic stem cells and breast cancer stem cells, and potential cancer therapy strategies based on their structures and functions. Glycoconj J 2022; 39:177-195. [PMID: 35267131 DOI: 10.1007/s10719-021-10032-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 11/27/2021] [Accepted: 12/08/2021] [Indexed: 12/26/2022]
Abstract
Expression profiles of glycosphingolipids (GSLs) in human embryonic stem cell (hESC) lines and their differentiated embryoid body (EB) outgrowth cells, consisting of three germ layers, were surveyed systematically. Several globo- and lacto-series GSLs were identified in undifferentiated hESCs and during differentiation of hESCs to EB outgrowth cells, and core structure switching of these GSLs to gangliosides was observed. Such switching was attributable to altered expression of key glycosyltransferases (GTs) in GSL biosynthetic pathways, reflecting the unique stage-specific transitions and mechanisms characteristic of the differentiation process. Lineage-specific differentiation of hESCs was associated with further GSL alterations. During differentiation of undifferentiated hESCs to neural progenitor cells, core structure switching from globo- and lacto-series to primarily gangliosides (particularly GD3) was again observed. During differentiation to endodermal cells, alterations of GSL profiles were distinct from those in differentiation to EB outgrowth or neural progenitor cells, with high expression of Gb4Cer and low expression of stage-specific embryonic antigen (SSEA)-3, -4, or GD3 in endodermal cells. Again, such profile changes resulted from alterations of key GTs in GSL biosynthetic pathways. Novel glycan structures identified on hESCs and their differentiated counterparts presumably play functional roles in hESCs and related cancer or cancer stem cells, and will be useful as surface biomarkers. We also examined GSL expression profiles in breast cancer stem cells (CSCs), using a model of epithelial-mesenchymal transition (EMT)-induced human breast CSCs. We found that GD2 and GD3, together with their common upstream GTs, GD3 synthase (GD3S) and GD2/GM2 synthase, maintained stem cell phenotype in breast CSCs. Subsequent studies showed that GD3 was associated with epidermal growth factor receptor (EGFR), and activated EGFR signaling in breast CSCs and breast cancer cell lines. GD3S knockdown enhanced cytotoxicity of gefitinib (an EGFR kinase inhibitor) in resistant MDA-MB468 cells, both in vitro and in vivo. Our findings indicate that GD3S contributes to gefitinib resistance in EGFR-positive breast cancer cells, and is a potentially useful therapeutic target in drug-resistant breast cancers.
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Li X, Li S, Liu Y, He Q, Liu W, Lin C, Miao W. HbLFG1, a Rubber Tree ( Hevea brasiliensis) Lifeguard Protein, Can Facilitate Powdery Mildew Infection by Suppressing Plant Immunity. PHYTOPATHOLOGY 2021; 111:1648-1659. [PMID: 34047620 DOI: 10.1094/phyto-08-20-0362-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Powdery mildew causes substantial losses in crop and economic plant yields worldwide. Although powdery mildew infection of rubber trees (Hevea brasiliensis), caused by the biotrophic fungus Erysiphe quercicola, severely threatens natural rubber production, little is known about the mechanism by which E. quercicola adapts to H. brasiliensis to invade the host plant. In barley and Arabidopsis thaliana, lifeguard (LFG) proteins, which have topological similarity to BAX INHIBITOR-1, are involved in host plant susceptibility to powdery mildew infection. In this study, we characterized an H. brasiliensis LFG protein (HbLFG1) with a focus on its function in regulating defense against powdery mildew. HbLFG1 gene expression was found to be upregulated during E. quercicola infection. HbLFG1 showed conserved functions in cell death inhibition and membrane localization. Expression of HbLFG1 in Nicotiana benthamiana leaves and A. thaliana Col-0 was demonstrated to significantly suppress callose deposition induced by conserved pathogen-associated molecular patterns chitin and flg22. Furthermore, we found that overexpression of HbLFG1 in H. brasiliensis mesophyll protoplasts significantly suppressed the chitin-induced burst of reactive oxygen species. Although A. thaliana Col-0 and E. quercicola displayed an incompatible interaction, Col-0 transformants overexpressing HbLFG1 were shown to be susceptible to E. quercicola. Collectively, the findings of this study provide evidence that HbLFG1 acts as a negative regulator of plant immunity that facilitates E. quercicola infection in H. brasiliensis.
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Affiliation(s)
- Xiao Li
- College of Plant Protection, Hainan University, Haikou 570228, China
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Hainan University), Ministry of Education, Haikou 570228, China
| | - Sipeng Li
- College of Plant Protection, Hainan University, Haikou 570228, China
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Hainan University), Ministry of Education, Haikou 570228, China
| | - Yuhan Liu
- College of Plant Protection, Hainan University, Haikou 570228, China
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Hainan University), Ministry of Education, Haikou 570228, China
| | - Qiguang He
- College of Plant Protection, Hainan University, Haikou 570228, China
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Hainan University), Ministry of Education, Haikou 570228, China
| | - Wenbo Liu
- College of Plant Protection, Hainan University, Haikou 570228, China
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Hainan University), Ministry of Education, Haikou 570228, China
| | - Chunhua Lin
- College of Plant Protection, Hainan University, Haikou 570228, China
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Hainan University), Ministry of Education, Haikou 570228, China
| | - Weiguo Miao
- College of Plant Protection, Hainan University, Haikou 570228, China
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests (Hainan University), Ministry of Education, Haikou 570228, China
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Tu Z, Hou S, Zheng Y, Abuduli M, Onder T, Intlekofer AM, Karnoub AE. In vivo library screening identifies the metabolic enzyme aldolase A as a promoter of metastatic lung colonization. iScience 2021; 24:102425. [PMID: 34036247 PMCID: PMC8138724 DOI: 10.1016/j.isci.2021.102425] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 02/22/2021] [Accepted: 04/09/2021] [Indexed: 11/23/2022] Open
Abstract
Elucidations of the factors that promote the growth of disseminated tumor cells (DTCs) into life-threatening lesions stand to provide much needed prognostic and therapeutic targets of translational utility for patients with metastatic cancer. To identify such regulators, we conducted gain-of-function cDNA library screening to discover genes that foster prostate cancer cell colonization of mouse lungs as an experimental model. Our efforts identified the metabolic enzyme aldolase A (ALDOA) as a driver of cancer cell motility, anchorage-independent growth, and metastatic colonization, and as a prognosticator of adverse patient outcome across many malignancies, including prostate, breast, pancreatic, and liver cancers. Metabolomics coupled with biochemical and functional analyses revealed that ALDOA triggered the activation of adenosine-5'-monophosphate (AMP)-activated protein kinase (AMPK), which we demonstrate played essential promalignant activities in ALDOA-expressing cells. Collectively, these findings unveiled vivo approaches to identify metastatic colonization regulators and uncovered previously undescribed roles for ALDOA-AMPK pathway in tumor progression.
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Affiliation(s)
- Zhenbo Tu
- Department of Pathology and Cancer Center, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Shengqi Hou
- Human Oncology and Pathogenesis Program and Department of Medicine, Memorial Sloan Kettering Cancer Center, New York 10065, USA
| | - Yurong Zheng
- Department of Pathology and Cancer Center, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Maerjianghan Abuduli
- Department of Pathology and Cancer Center, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Tamer Onder
- Department of Molecular Biology and Genetics, School of Medicine, Koç University, Istanbul 34450, Turkey
| | - Andrew M. Intlekofer
- Human Oncology and Pathogenesis Program and Department of Medicine, Memorial Sloan Kettering Cancer Center, New York 10065, USA
| | - Antoine E. Karnoub
- Department of Pathology and Cancer Center, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
- Harvard Stem Cell Institute, Cambridge, MA 02138, USA
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
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Sakuma C, Sekizuka T, Kuroda M, Hanada K, Yamaji T. Identification of SYS1 as a Host Factor Required for Shiga Toxin-Mediated Cytotoxicity in Vero Cells. Int J Mol Sci 2021; 22:ijms22094936. [PMID: 34066520 PMCID: PMC8124574 DOI: 10.3390/ijms22094936] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/01/2021] [Accepted: 05/04/2021] [Indexed: 12/12/2022] Open
Abstract
Shiga toxin (STx) or Vero toxin is a virulence factor produced by enterohemorrhagic Escherichia coli. The toxin binds to the glycosphingolipid globotriaosylceramide (Gb3) for its entry, and causes cell death by inhibiting ribosome function. Previously, we performed a loss-of-function screen in HeLa cells using a human CRISPR knockout (KO) library and identified various host genes required for STx-induced cell death. To determine whether this library targeted to the human genome is applicable to non-human primate cells and to identify previously unrecognized factors crucial for STx-induced cell death, we herein performed a similar screen in the African green monkey kidney-derived Vero C1008 subline. Many genes relevant to metabolic enzymes and membrane trafficking were enriched, although the number of enriched genes was less than that obtained in the screening for HeLa cells. Of note, several genes that had not been enriched in the previous screening were enriched: one of these genes was SYS1, which encodes a multi-spanning membrane protein in the Golgi apparatus. In SYS1 KO Vero cells, expression of Gb3 and sphingomyelin was decreased, while that of glucosylceramide and lactosylceramide was increased. In addition, loss of SYS1 inhibited the biosynthesis of protein glycans, deformed the Golgi apparatus, and perturbed the localization of trans-Golgi network protein (TGN) 46. These results indicate that the human CRISPR KO library is applicable to Vero cell lines, and SYS1 has a widespread effect on glycan biosynthesis via regulation of intra-Golgi and endosome–TGN retrograde transports.
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Affiliation(s)
- Chisato Sakuma
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan; (C.S.); (K.H.)
| | - Tsuyoshi Sekizuka
- Pathogen Genomics Center, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan; (T.S.); (M.K.)
| | - Makoto Kuroda
- Pathogen Genomics Center, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan; (T.S.); (M.K.)
| | - Kentaro Hanada
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan; (C.S.); (K.H.)
| | - Toshiyuki Yamaji
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan; (C.S.); (K.H.)
- Correspondence:
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13
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Cebolla VL, Jarne C, Vela J, Garriga R, Membrado L, Galbán J. Scanning densitometry and mass spectrometry for HPTLC analysis of lipids: The last 10 years. J LIQ CHROMATOGR R T 2021. [DOI: 10.1080/10826076.2020.1866600] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
| | - Carmen Jarne
- Instituto de Carboquímica, ICB-CSIC, Zaragoza, Spain
| | - Jesús Vela
- Departamento de Química Analítica, EINA, Universidad de Zaragoza, Zaragoza, Spain
| | - Rosa Garriga
- Departamento de Química Física, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain
| | - Luis Membrado
- Instituto de Carboquímica, ICB-CSIC, Zaragoza, Spain
| | - Javier Galbán
- Departamento de Química Analítica, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain
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14
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Akiyama H, Ide M, Yamaji T, Mizutani Y, Niimi Y, Mutoh T, Kamiguchi H, Hirabayashi Y. Galabiosylceramide is present in human cerebrospinal fluid. Biochem Biophys Res Commun 2020; 536:73-79. [PMID: 33360824 DOI: 10.1016/j.bbrc.2020.12.051] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 12/15/2020] [Indexed: 01/19/2023]
Abstract
Cerebrospinal fluid (CSF) contains glycosphingolipids, including lactosylceramide (LacCer, Galβ(1,4)Glcβ-ceramide). LacCer and its structural isomer, galabiosylceramide (Gb2, Galα(1,4)Galβ-ceramide), are classified as ceramide dihexosides (CDH). Gb2 is degraded by α-galactosidase A (GLA) in lysosomes, and genetic GLA deficiency causes Fabry disease, an X-linked lysosomal storage disorder. In patients with Fabry disease, Gb2 accumulates in organs throughout the body. While Gb2 has been reported to be in the liver, kidney, and urine of healthy individuals, its presence in CSF has not been reported, either in patients with Fabry disease or healthy controls. Here, we isolated CDH fractions from CSF of patients with idiopathic normal pressure hydrocephalus. Purified CDH fractions showed positive reaction with Shiga toxin, which specifically binds to the Galα(1,4)Galβ structure. The isolated CDH fractions were analyzed by hydrophilic interaction chromatography (HILIC)-electrospray ionization tandem mass spectrometry (ESI-MS/MS). HILIC-ESI-MS/MS separated LacCer and Gb2 and revealed the presence of Gb2 and LacCer in the fractions. We also found Gb2 in CSF from neurologically normal control subjects. This is the first report to show Gb2 exists in human CSF.
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Affiliation(s)
- Hisako Akiyama
- RIKEN Center for Brain Science, Wako, Saitama, 351-0198, Japan.
| | - Mitsuko Ide
- Cellular Informatics Laboratory, RIKEN, Wako, Saitama, 351-0198, Japan
| | - Toshiyuki Yamaji
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, 162-8640, Japan
| | - Yasuaki Mizutani
- Department of Neurology, Fujita Health University School of Medicine, Toyoake, Aichi, 470-1192, Japan
| | - Yoshiki Niimi
- Department of Neurology, Fujita Health University School of Medicine, Toyoake, Aichi, 470-1192, Japan
| | - Tatsuro Mutoh
- Department of Neurology, Fujita Health University School of Medicine, Toyoake, Aichi, 470-1192, Japan
| | | | - Yoshio Hirabayashi
- Cellular Informatics Laboratory, RIKEN, Wako, Saitama, 351-0198, Japan; Institute for Environmental and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, Chiba, 279-0021, Japan
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15
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Farabi K, Manabe Y, Ichikawa H, Miyake S, Tsutsui M, Kabayama K, Yamaji T, Tanaka K, Hung SC, Fukase K. Concise and Reliable Syntheses of Glycodendrimers via Self-Activating Click Chemistry: A Robust Strategy for Mimicking Multivalent Glycan-Pathogen Interactions. J Org Chem 2020; 85:16014-16023. [PMID: 33058668 DOI: 10.1021/acs.joc.0c01547] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Individual interactions between glycans and their receptors are usually weak, although these weak interactions can combine to realize a strong interaction (multivalency). Such multivalency plays a crucial role in the recognition of host cells by pathogens. Glycodendrimers are useful materials for the reconstruction of this multivalent interaction. However, the introduction of a large number of glycans to a dendrimer core is fraught with difficulties. We herein synthesized antipathogenic glycodendrimers using the self-activating click chemistry (SACC) method developed by our group. The excellent reactivity of SACC enabled the efficient preparation of sialyl glycan and Gb3 glycan dendrimers, which exhibited strong avidity toward hemagglutinin on influenza virus and Shiga toxin B subunit produced by Escherichia coli, respectively. We demonstrated the usefulness of SACC-based glycodendrimers as antipathogenic compounds.
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Affiliation(s)
- Kindi Farabi
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan
| | - Yoshiyuki Manabe
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan.,Core for Medicine and Science Collaborative Research and Education, Project Research Center for Fundamental Sciences, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan
| | - Hiroaki Ichikawa
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan
| | - Shuto Miyake
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan
| | - Masato Tsutsui
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan
| | - Kazuya Kabayama
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan.,Core for Medicine and Science Collaborative Research and Education, Project Research Center for Fundamental Sciences, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan
| | - Toshiyuki Yamaji
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Toyama 1-23-1, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Katsunori Tanaka
- Biofunctional Synthetic Chemistry Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.,School of Materials and Chemical Technology, Department of Chemical Science and Engineering, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Shang-Cheng Hung
- Genomics Research Center, Academia Sinica, 128, Section 2, Academia Road, Taipei 115, Taiwan
| | - Koichi Fukase
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan.,Core for Medicine and Science Collaborative Research and Education, Project Research Center for Fundamental Sciences, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan
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16
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Akintayo A, Mayoral J, Asada M, Tang J, Sundaram S, Stanley P. Point mutations that inactivate MGAT4D-L, an inhibitor of MGAT1 and complex N-glycan synthesis. J Biol Chem 2020; 295:14053-14064. [PMID: 32763972 DOI: 10.1074/jbc.ra120.014784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/31/2020] [Indexed: 11/06/2022] Open
Abstract
The membrane-bound, long form of MGAT4D, termed MGAT4D-L, inhibits MGAT1 activity in transfected cells and reduces the generation of complex N-glycans. MGAT1 is the GlcNAc-transferase that initiates complex and hybrid N-glycan synthesis. We show here that Drosophila MGAT1 was also inhibited by MGAT4D-L in S2 cells. In mammalian cells, expression of MGAT4D-L causes the substrate of MGAT1 (Man5GlcNAc2Asn) to accumulate on glycoproteins, a change that is detected by the lectin Galanthus nivalis agglutinin (GNA). Using GNA binding as an assay for the inhibition of MGAT1 in MGAT4D-L transfectants, we performed site-directed mutagenesis to determine requirements for MGAT1 inhibition. Deletion of 25 amino acids (aa) from the C terminus inactivated MGAT4D-L, but deletion of 20 aa did not. Conversion of the five key amino acids (PSLFQ) to Ala, or deletion of PSLFQ in the context of full-length MGAT4D-L, also inactivated MGAT1 inhibitory activity. Nevertheless, mutant, inactive MGAT4D-L interacted with MGAT1 in co-immuno-precipitation experiments. The PSLFQ sequence also occurs in MGAT4A and MGAT4B GlcNAc-transferases. However, neither inhibited MGAT1 in transfected CHO cells. MGAT4D-L inhibitory activity could be partially transferred by attaching PSLFQ or the 25-aa C terminus of MGAT4D-L to the C terminus of MGAT1. Mutation of each amino acid in PSLFQ to Ala identified both Leu and Phe as independently essential for MGAT4D-L activity. Thus, replacement of either Leu-395 or Phe-396 with Ala led to inactivation of MGAT4D-L inhibitory activity. These findings provide new insights into the mechanism of inhibition of MGAT1 by MGAT4D-L, and for the development of small molecule inhibitors of MGAT1.
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Affiliation(s)
- Ayodele Akintayo
- Dept. of Cell Biology, Albert Einstein College of Medicine, New York, New York
| | - Joshua Mayoral
- Dept. of Cell Biology, Albert Einstein College of Medicine, New York, New York
| | - Masahiro Asada
- Dept. of Cell Biology, Albert Einstein College of Medicine, New York, New York
| | - Jian Tang
- Dept. of Cell Biology, Albert Einstein College of Medicine, New York, New York
| | - Subha Sundaram
- Dept. of Cell Biology, Albert Einstein College of Medicine, New York, New York
| | - Pamela Stanley
- Dept. of Cell Biology, Albert Einstein College of Medicine, New York, New York
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17
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Morimoto K, Suzuki N, Tanida I, Kakuta S, Furuta Y, Uchiyama Y, Hanada K, Suzuki Y, Yamaji T. Blood group P1 antigen-bearing glycoproteins are functional but less efficient receptors of Shiga toxin than conventional glycolipid-based receptors. J Biol Chem 2020; 295:9490-9501. [PMID: 32409578 DOI: 10.1074/jbc.ra120.013926] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 05/12/2020] [Indexed: 12/29/2022] Open
Abstract
Shiga toxin (STx) is a virulence factor produced by enterohemorrhagic Escherichia coli. STx is taken up by mammalian host cells by binding to the glycosphingolipid (GSL) globotriaosylceramide (Gb3; Galα1-4Galβ1-4Glc-ceramide) and causes cell death after its retrograde membrane transport. However, the contribution of the hydrophobic portion of Gb3 (ceramide) to STx transport remains unclear. In pigeons, blood group P1 glycan antigens (Galα1-4Galβ1-4GlcNAc-) are expressed on glycoproteins that are synthesized by α1,4-galactosyltransferase 2 (pA4GalT2). To examine whether these glycoproteins can also function as STx receptors, here we constructed glycan-remodeled HeLa cell variants lacking Gb3 expression but instead expressing pA4GalT2-synthesized P1 glycan antigens on glycoproteins. We compared STx binding and sensitivity of these variants with those of the parental, Gb3-expressing HeLa cells. The glycan-remodeled cells bound STx1 via N-glycans of glycoproteins and were sensitive to STx1 even without Gb3 expression, indicating that P1-containing glycoproteins also function as STx receptors. However, these variants were significantly less sensitive to STx than the parent cells. Fluorescence microscopy and correlative light EM revealed that the STx1 B subunit accumulates to lower levels in the Golgi apparatus after glycoprotein-mediated than after Gb3-mediated uptake but instead accumulates in vacuole-like structures probably derived from early endosomes. Furthermore, coexpression of Galα1-4Gal on both glycoproteins and GSLs reduced the sensitivity of cells to STx1 compared with those expressing Galα1-4Gal only on GSLs, probably because of competition for STx binding or internalization. We conclude that lipid-based receptors are much more effective in STx retrograde transport and mediate greater STx cytotoxicity than protein-based receptors.
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Affiliation(s)
- Kanta Morimoto
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Tokyo, Japan.,Department of Materials and Applied Chemistry, College of Science and Technology, Nihon University, Tokyo, Japan
| | - Noriko Suzuki
- Graduate School of Science and Technology, Niigata University, Niigata, Japan
| | - Isei Tanida
- Department of Cellular and Molecular Neuropathology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Soichiro Kakuta
- Department of Cellular and Molecular Neuropathology, Juntendo University Graduate School of Medicine, Tokyo, Japan.,Laboratory of Morphology and Image Analysis, Biomedical Research Center, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Yoko Furuta
- Department of Cellular and Molecular Neuropathology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Yasuo Uchiyama
- Department of Cellular and Molecular Neuropathology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Kentaro Hanada
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Yusuke Suzuki
- Department of Materials and Applied Chemistry, College of Science and Technology, Nihon University, Tokyo, Japan
| | - Toshiyuki Yamaji
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Tokyo, Japan
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18
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Hong CJ, Yeon J, Yeo BK, Woo H, An HK, Heo W, Kim K, Yu SW. Fas-apoptotic inhibitory molecule 2 localizes to the lysosome and facilitates autophagosome-lysosome fusion through the LC3 interaction region motif-dependent interaction with LC3. FASEB J 2020; 34:161-179. [PMID: 31914609 DOI: 10.1096/fj.201901626r] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 09/20/2019] [Accepted: 10/08/2019] [Indexed: 01/08/2023]
Abstract
Fas-apoptotic inhibitory molecule 2 (FAIM2) is a member of the transmembrane BAX inhibitor motif-containing (TMBIM) family. TMBIM family is comprised of six anti-apoptotic proteins that suppress cell death by regulating endoplasmic reticulum Ca2+ homeostasis. Recent studies have implicated two TMBIM proteins, GRINA and BAX Inhibitor-1, in mediating cytoprotection via autophagy. However, whether FAIM2 plays a role in autophagy has been unknown. Here we show that FAIM2 localizes to the lysosomes at basal state and facilitates autophagy through interaction with microtubule-associated protein 1 light chain 3 proteins in human neuroblastoma SH-SY5Y cells. FAIM2 overexpression increased autophagy flux, while autophagy flux was impaired in shRNA-mediated knockdown (shFAIM2) cells, and the impairment was more evident in the presence of rapamycin. In shFAIM2 cells, autophagosome maturation through fusion with lysosomes was impaired, leading to accumulation of autophagosomes. A functional LC3-interacting region motif within FAIM2 was essential for the interaction with LC3 and rescue of autophagy flux in shFAIM2 cells while LC3-binding property of FAIM2 was dispensable for the anti-apoptotic function in response to Fas receptor-mediated apoptosis. Suppression of autophagosome maturation was also observed in a null mutant of Caenorhabditis elegans lacking xbx-6, the ortholog of FAIM2. Our study suggests that FAIM2 is a novel regulator of autophagy mediating autophagosome maturation through the interaction with LC3.
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Affiliation(s)
- Caroline Jeeyeon Hong
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
| | - Jihye Yeon
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
| | - Bo Kyoung Yeo
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
| | - Hanwoong Woo
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
| | - Hyun-Kyu An
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
| | - Woojung Heo
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
| | - Kyuhyung Kim
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
| | - Seong-Woon Yu
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
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19
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Preparation of Fluorescent Recombinant Shiga Toxin B Subunit and Its Application to Flow Cytometry. Methods Mol Biol 2020; 2132:463-474. [PMID: 32306353 DOI: 10.1007/978-1-0716-0430-4_45] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Shiga toxin (Stx) is a major virulence factor of enterohemorrhagic Escherichia coli (E. coli). Stx consists of one enzymatic A subunit and five B subunits (StxB) that are involved in binding. The StxB pentamer specifically recognizes a glycosphingolipid, globotriaosylceramide (Gb3), as a receptor; therefore, it can be used as a probe to detect Gb3. This chapter describes the preparation of recombinant Stx1B proteins using E. coli, their conjugation with fluorescent dyes, and their application for flow cytometry. The prepared fluorescent StxB proteins bound to cells of several lines, including the HeLa human cervix adenocarcinoma cell line and the THP-1 human monocytic leukemia cell line. Furthermore, the probe was useful for confirmation of several sphingolipid-deficient HeLa cell lines that were constructed using genome editing.
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20
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Tachida Y, Kumagai K, Sakai S, Ando S, Yamaji T, Hanada K. Chlamydia trachomatis-infected human cells convert ceramide to sphingomyelin without sphingomyelin synthases 1 and 2. FEBS Lett 2019; 594:519-529. [PMID: 31596951 DOI: 10.1002/1873-3468.13632] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 09/27/2019] [Accepted: 09/27/2019] [Indexed: 12/19/2022]
Abstract
The obligate intracellular bacterium Chlamydia trachomatis proliferates in the membranous compartment inclusion formed in host cells. The host ceramide transport protein CERT delivers ceramide from the endoplasmic reticulum to the Golgi complex for the synthesis of sphingomyelin (SM). Chlamydia trachomatis has been suggested to employ CERT to produce SM in the inclusion by host SM synthases (SMSs). Here, we found that C. trachomatis proliferates and produces infective progeny even in SMS1 and SMS2 double-knockout HeLa cells, but not in the SMS1/SMS2/CERT triple-knockout cells. Interestingly, infected cells convert ceramide to SM without host SMSs. These results suggest that C. trachomatis-infected cells can convert ceramide to SM without host SMSs after CERT-mediated transfer of ceramide to the inclusions.
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Affiliation(s)
- Yuriko Tachida
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Japan
| | - Keigo Kumagai
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Japan
| | - Shota Sakai
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Japan
| | - Shuji Ando
- Department of Virology I, National Institute of Infectious Diseases, Shinjuku-ku, Japan
| | - Toshiyuki Yamaji
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Japan
| | - Kentaro Hanada
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Japan
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21
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Jiménez-González V, Ogalla-García E, García-Quintanilla M, García-Quintanilla A. Deciphering GRINA/Lifeguard1: Nuclear Location, Ca 2+ Homeostasis and Vesicle Transport. Int J Mol Sci 2019; 20:ijms20164005. [PMID: 31426446 PMCID: PMC6719933 DOI: 10.3390/ijms20164005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 07/31/2019] [Accepted: 08/12/2019] [Indexed: 01/31/2023] Open
Abstract
The Glutamate Receptor Ionotropic NMDA-Associated Protein 1 (GRINA) belongs to the Lifeguard family and is involved in calcium homeostasis, which governs key processes, such as cell survival or the release of neurotransmitters. GRINA is mainly associated with membranes of the endoplasmic reticulum, Golgi, endosome, and the cell surface, but its presence in the nucleus has not been explained yet. Here we dissect, with the help of different software tools, the potential roles of GRINA in the cell and how they may be altered in diseases, such as schizophrenia or celiac disease. We describe for the first time that the cytoplasmic N-terminal half of GRINA (which spans a Proline-rich domain) contains a potential DNA-binding sequence, in addition to cleavage target sites and probable PY-nuclear localization sequences, that may enable it to be released from the rest of the protein and enter the nucleus under suitable conditions, where it could participate in the transcription, alternative splicing, and mRNA export of a subset of genes likely involved in lipid and sterol synthesis, ribosome biogenesis, or cell cycle progression. To support these findings, we include additional evidence based on an exhaustive review of the literature and our preliminary data of the protein–protein interaction network of GRINA.
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Affiliation(s)
| | - Elena Ogalla-García
- Department of Pharmacology, School of Pharmacy, University of Seville, 41012 Seville, Spain
| | - Meritxell García-Quintanilla
- Institute of Biomedicine of Seville (IBiS), University Hospital Virgen del Rocío/CSIC/University of Seville, 41013 Seville, Spain
| | - Albert García-Quintanilla
- Department of Biochemistry and Molecular Biology, School of Pharmacy, University of Seville, 41012 Seville, Spain.
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22
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Pothukuchi P, Agliarulo I, Russo D, Rizzo R, Russo F, Parashuraman S. Translation of genome to glycome: role of the Golgi apparatus. FEBS Lett 2019; 593:2390-2411. [PMID: 31330561 DOI: 10.1002/1873-3468.13541] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 07/12/2019] [Accepted: 07/15/2019] [Indexed: 12/16/2022]
Abstract
Glycans are one of the four biopolymers of the cell and they play important roles in cellular and organismal physiology. They consist of both linear and branched structures and are synthesized in a nontemplated manner in the secretory pathway of mammalian cells with the Golgi apparatus playing a key role in the process. In spite of the absence of a template, the glycans synthesized by a cell are not a random collection of possible glycan structures but a distribution of specific glycans in defined quantities that is unique to each cell type (Cell type here refers to distinct cell forms present in an organism that can be distinguished based on morphological, phenotypic and/or molecular criteria.) While information to produce cell type-specific glycans is encoded in the genome, how this information is translated into cell type-specific glycome (Glycome refers to the quantitative distribution of all glycan structures present in a given cell type.) is not completely understood. We summarize here the factors that are known to influence the fidelity of glycan biosynthesis and integrate them into known glycosylation pathways so as to rationalize the translation of genetic information to cell type-specific glycome.
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Affiliation(s)
- Prathyush Pothukuchi
- Institute of Biochemistry and Cellular Biology, National Research Council of Italy, Napoli, Italy
| | - Ilenia Agliarulo
- Institute of Biochemistry and Cellular Biology, National Research Council of Italy, Napoli, Italy
| | - Domenico Russo
- Institute of Biochemistry and Cellular Biology, National Research Council of Italy, Napoli, Italy
| | - Riccardo Rizzo
- Institute of Biochemistry and Cellular Biology, National Research Council of Italy, Napoli, Italy
| | - Francesco Russo
- Institute of Biochemistry and Cellular Biology, National Research Council of Italy, Napoli, Italy
| | - Seetharaman Parashuraman
- Institute of Biochemistry and Cellular Biology, National Research Council of Italy, Napoli, Italy
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23
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Yamaji T, Sekizuka T, Tachida Y, Sakuma C, Morimoto K, Kuroda M, Hanada K. A CRISPR Screen Identifies LAPTM4A and TM9SF Proteins as Glycolipid-Regulating Factors. iScience 2019; 11:409-424. [PMID: 30660999 PMCID: PMC6348303 DOI: 10.1016/j.isci.2018.12.039] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 11/13/2018] [Accepted: 12/28/2018] [Indexed: 12/02/2022] Open
Abstract
Glycosphingolipids (GSLs) are produced by various GSL-synthesizing enzymes, but post-translational regulation of these enzymes is incompletely understood. To address this knowledge disparity, we focused on biosynthesis of globotriaosylceramide (Gb3), the Shiga toxin (STx) receptor, and performed a genome-wide CRISPR/CAS9 knockout screen in HeLa cells using STx1-mediated cytotoxicity. We identified various genes including sphingolipid-related genes and membrane-trafficking genes. In addition, we found two proteins, LAPTM4A and TM9SF2, for which physiological roles remain elusive. Disruption of either LAPTM4A or TM9SF2 genes reduced Gb3 biosynthesis, resulting in accumulation of its precursor, lactosylceramide. Loss of LAPTM4A decreased endogenous Gb3 synthase activity in a post-transcriptional mechanism, whereas loss of TM9SF2 did not affect Gb3 synthase activity but instead disrupted localization of Gb3 synthase. Furthermore, the Gb3-regulating activity of TM9SF2 was conserved in the TM9SF family. These results provide mechanistic insight into the post-translational regulation of the activity and localization of Gb3 synthase. Genome-wide CRISPR knockout screening using Shiga toxin-induced cell death Both LAPTM4A and TM9SF2 are required for Gb3 biosynthesis Loss of LAPTM4A reduces Gb3 synthase activity post-transcriptionally TM9SF2 regulates the subcellular localization of Gb3 synthase
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Affiliation(s)
- Toshiyuki Yamaji
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan.
| | - Tsuyoshi Sekizuka
- Pathogen Genomics Center, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Yuriko Tachida
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Chisato Sakuma
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Kanta Morimoto
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan; Department of Materials and Applied Chemistry, College of Science and Technology, Nihon University, Chiyoda-ku, Tokyo 101-8308, Japan
| | - Makoto Kuroda
- Pathogen Genomics Center, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Kentaro Hanada
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
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Transmembrane protein GRINA modulates aerobic glycolysis and promotes tumor progression in gastric cancer. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2018; 37:308. [PMID: 30541591 PMCID: PMC6292005 DOI: 10.1186/s13046-018-0974-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2018] [Accepted: 11/21/2018] [Indexed: 12/17/2022]
Abstract
BACKGROUND Recent observations indicate a decreased cancer risk in patients with Alzheimer's disease (AD). AD is a severe neurodegenerative disorder characterized by progressive cognitive decline. The 8q24 region has been shown to be involved in AD aetiology. We aimed to identify and explore the potential oncogenes or antioncogenes on chromosome 8q24. METHODS We compared expression of genes on Chromosome 8q24 in 32 pairs of samples from The Cancer Genome Atlas (TCGA) database. We conducted bioinformatics analysis of the commonly used gastric cancer databases and performed clinical verification of gastric cancer samples, combined with assessment of biological function both in vitro and in vivo to determine the relationship between upregulated expression of GRINA and gastric cancer progression. We also explored the molecular mechanism of GRINA upregulation and its function in gastric cancer development and progression. RESULTS The expression of GRINA in cancer tissues was significantly higher than that in normal tissues. GRINA indicated poor prognosis in gastric cancer. GRINA promoted the proliferation, migration and invasion capacity of gastric cancer cells. GRINA was transcriptionally mediated by c-Myc and promotes cell cycle transition. GRINA knockdown decreased PI3K/Akt/mTOR signaling and glycolytic metabolism in gastric cancer cells. The apoptosis rate was significantly increased in gastric cancer cell lines after knockdown of GRINA. The expression of pro-apoptotic protein Bax was significantly upregulated, whereas the anti-apoptotic protein Bcl-2 was significantly downregulated in GRINA silenced cells. CONCLUSIONS Human gastric cancers have increased levels of GRINA, which promotes growth of gastric cancer and inhibits tumor cells apoptosis.
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Fielding CA, Weekes MP, Nobre LV, Ruckova E, Wilkie GS, Paulo JA, Chang C, Suárez NM, Davies JA, Antrobus R, Stanton RJ, Aicheler RJ, Nichols H, Vojtesek B, Trowsdale J, Davison AJ, Gygi SP, Tomasec P, Lehner PJ, Wilkinson GWG. Control of immune ligands by members of a cytomegalovirus gene expansion suppresses natural killer cell activation. eLife 2017; 6:e22206. [PMID: 28186488 PMCID: PMC5367895 DOI: 10.7554/elife.22206] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2016] [Accepted: 02/09/2017] [Indexed: 01/31/2023] Open
Abstract
The human cytomegalovirus (HCMV) US12 family consists of ten sequentially arranged genes (US12-21) with poorly characterized function. We now identify novel natural killer (NK) cell evasion functions for four members: US12, US14, US18 and US20. Using a systematic multiplexed proteomics approach to quantify ~1300 cell surface and ~7200 whole cell proteins, we demonstrate that the US12 family selectively targets plasma membrane proteins and plays key roles in regulating NK ligands, adhesion molecules and cytokine receptors. US18 and US20 work in concert to suppress cell surface expression of the critical NKp30 ligand B7-H6 thus inhibiting NK cell activation. The US12 family is therefore identified as a major new hub of immune regulation.
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Affiliation(s)
- Ceri A Fielding
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Michael P Weekes
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, United Kingdom
- Department of Cell Biology, Harvard Medical School, Boston, United States
| | - Luis V Nobre
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, United Kingdom
| | - Eva Ruckova
- Regional Centre for Applied Molecular Oncology, Masaryk Memorial Cancer Institute, Brno, Czech Republic
| | - Gavin S Wilkie
- MRC-University of Glasgow Centre for Virus Research, University of Glasgow, Glasgow, United Kingdom
| | - Joao A Paulo
- Department of Cell Biology, Harvard Medical School, Boston, United States
| | - Chiwen Chang
- Immunology Division, Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Nicolás M Suárez
- MRC-University of Glasgow Centre for Virus Research, University of Glasgow, Glasgow, United Kingdom
| | - James A Davies
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Robin Antrobus
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, United Kingdom
| | - Richard J Stanton
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Rebecca J Aicheler
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Hester Nichols
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Borek Vojtesek
- Regional Centre for Applied Molecular Oncology, Masaryk Memorial Cancer Institute, Brno, Czech Republic
| | - John Trowsdale
- Immunology Division, Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Andrew J Davison
- MRC-University of Glasgow Centre for Virus Research, University of Glasgow, Glasgow, United Kingdom
| | - Steven P Gygi
- Department of Cell Biology, Harvard Medical School, Boston, United States
| | - Peter Tomasec
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Paul J Lehner
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, United Kingdom
| | - Gavin W G Wilkinson
- Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
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Liu Q. TMBIM-mediated Ca 2+ homeostasis and cell death. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:850-857. [PMID: 28064000 DOI: 10.1016/j.bbamcr.2016.12.023] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2016] [Revised: 12/22/2016] [Accepted: 12/22/2016] [Indexed: 11/25/2022]
Abstract
Ca2+ is a ubiquitous intracellular messenger that regulates numerous physiological activities in humans, animals, plants, and bacteria. Cytosolic Ca2+ is kept at a low level, but subcellular organelles such as the endoplasmic reticulum (ER) and Golgi apparatus maintain high-concentration Ca2+ stores. Under resting conditions, store Ca2+ homeostasis is dynamically regulated to equilibrate between active Ca2+ uptake and passive Ca2+ leak processes. The evolutionarily conserved Transmembrane BAX Inhibitor-1 Motif-containing (TMBIM) proteins mediate Ca2+ homeostasis and cell death. This review focuses on recent advances in functional and structural analysis of TMBIM proteins in regulation of the two related functions. The roles of TMBIM proteins in pathogen infection and cancer are also discussed with prospects for treatment. This article is part of a Special Issue entitled: ECS Meeting edited by Claus Heizmann, Joachim Krebs and Jacques Haiech.
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Affiliation(s)
- Qun Liu
- Biology Department, Brookhaven National Laboratory, Upton, NY 11973, USA.
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27
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Yamaji T, Horie A, Tachida Y, Sakuma C, Suzuki Y, Kushi Y, Hanada K. Role of Intracellular Lipid Logistics in the Preferential Usage of Very Long Chain-Ceramides in Glucosylceramide. Int J Mol Sci 2016; 17:ijms17101761. [PMID: 27775668 PMCID: PMC5085785 DOI: 10.3390/ijms17101761] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 10/11/2016] [Accepted: 10/14/2016] [Indexed: 11/16/2022] Open
Abstract
Ceramide is a common precursor of sphingomyelin (SM) and glycosphingolipids (GSLs) in mammalian cells. Ceramide synthase 2 (CERS2), one of the six ceramide synthase isoforms, is responsible for the synthesis of very long chain fatty acid (C20–26 fatty acids) (VLC)-containing ceramides (VLC-Cer). It is known that the proportion of VLC species in GSLs is higher than that in SM. To address the mechanism of the VLC-preference of GSLs, we used genome editing to establish three HeLa cell mutants that expressed different amounts of CERS2 and compared the acyl chain lengths of SM and GSLs by metabolic labeling experiments. VLC-sphingolipid expression was increased along with that of CERS2, and the proportion of VLC species in glucosylceramide (GlcCer) was higher than that in SM for all expression levels of CERS2. This higher proportion was still maintained even when the proportion of C16-Cer to the total ceramides was increased by disrupting the ceramide transport protein (CERT)-dependent C16-Cer delivery pathway for SM synthesis. On the other hand, merging the Golgi apparatus and the endoplasmic reticulum (ER) by Brefeldin A decreased the proportion of VLC species in GlcCer probably due to higher accessibility of UDP-glucose ceramide glucosyltransferase (UGCG) to C16-rich ceramides. These results suggest the existence of a yet-to-be-identified mechanism rendering VLC-Cer more accessible than C16-Cer to UGCG, which is independent of CERT.
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Affiliation(s)
- Toshiyuki Yamaji
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan.
| | - Aya Horie
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan.
- Department of Materials and Applied Chemistry, College of Science and Technology, Nihon University, Chiyoda-ku, Tokyo 101-8308, Japan.
| | - Yuriko Tachida
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan.
| | - Chisato Sakuma
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan.
| | - Yusuke Suzuki
- Department of Materials and Applied Chemistry, College of Science and Technology, Nihon University, Chiyoda-ku, Tokyo 101-8308, Japan.
| | - Yasunori Kushi
- Department of Materials and Applied Chemistry, College of Science and Technology, Nihon University, Chiyoda-ku, Tokyo 101-8308, Japan.
| | - Kentaro Hanada
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan.
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Glycosphingolipid storage in Fabry mice extends beyond globotriaosylceramide and is affected by ABCB1 depletion. Future Sci OA 2016; 2:FSO147. [PMID: 28116130 PMCID: PMC5242178 DOI: 10.4155/fsoa-2016-0027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 08/10/2016] [Indexed: 11/17/2022] Open
Abstract
Aim: Fabry disease is caused by α-galactosidase A deficiency leading to accumulation of globotriaosylceramide (Gb3) in tissues. Clinical manifestations do not appear to correlate with total Gb3 levels. Studies examining tissue distribution of specific acyl chain species of Gb3 and upstream glycosphingolipids are lacking. Material & methods/Results: Thorough characterization of the Fabry mouse sphingolipid profile by LC-MS revealed unique Gb3 acyl chain storage profiles. Storage extended beyond Gb3; all Fabry tissues also accumulated monohexosylceramides. Depletion of ABCB1 had a complex effect on glycosphingolipid storage. Conclusion: These data provide insights into how specific sphingolipid species correlate with one another and how these correlations change in the α-galactosidase A-deficient state, potentially leading to the identification of more specific biomarkers of Fabry disease. Fabry disease is caused by a shortage of the enzyme α-galactosidase A leading to storage of a fat called globotriaosylceramide (Gb3) in tissues. Disease severity does not appear to correlate directly with total Gb3. Importantly, Gb3 is comprised of many highly related but distinct species. We examined levels of Gb3 species and precursor molecules in Fabry mice. Gb3 species and storage are unique to each tissue. Furthermore, storage is not limited to Gb3; precursor fats are also elevated. Detailed analyses of differences in storage between the normal and α-galactosidase A-deficient state may provide a better understanding of the causes of Fabry disease.
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Garcia-Quintanilla A, Miranzo-Navarro D. Extraintestinal manifestations of celiac disease: 33-mer gliadin binding to glutamate receptor GRINA as a new explanation. Bioessays 2016; 38:427-39. [PMID: 26990286 DOI: 10.1002/bies.201500143] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
We propose a biochemical mechanism for celiac disease and non-celiac gluten sensitivity that may rationalize many of the extradigestive disorders not explained by the current immunogenetic model. Our hypothesis is based on the homology between the 33-mer gliadin peptide and a component of the NMDA glutamate receptor ion channel - the human GRINA protein - using BLASTP software. Based on this homology the 33-mer may act as a natural antagonist interfering with the normal interactions of GRINA and its partners. The theory is supported by numerous independent data from the literature, and provides a mechanistic link with otherwise unrelated disorders, such as cleft lip and palate, thyroid dysfunction, restless legs syndrome, depression, ataxia, hearing loss, fibromyalgia, dermatitis herpetiformis, schizophrenia, toxoplasmosis, anemia, osteopenia, Fabry disease, Barret's adenocarcinoma, neuroblastoma, urinary incontinence, recurrent miscarriage, cardiac anomalies, reduced risk of breast cancer, stiff person syndrome, etc. The hypothesis also anticipates better animal models, and has the potential to open new avenues of research.
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Affiliation(s)
| | - Domingo Miranzo-Navarro
- Department of Biochemistry and Molecular Biology, School of Pharmacy, University of Seville, Spain
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30
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Urresti J, Ruiz-Meana M, Coccia E, Arévalo JC, Castellano J, Fernández-Sanz C, Galenkamp KMO, Planells-Ferrer L, Moubarak RS, Llecha-Cano N, Reix S, García-Dorado D, Barneda-Zahonero B, Comella JX. Lifeguard Inhibits Fas Ligand-mediated Endoplasmic Reticulum-Calcium Release Mandatory for Apoptosis in Type II Apoptotic Cells. J Biol Chem 2015; 291:1221-34. [PMID: 26582200 DOI: 10.1074/jbc.m115.677682] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Indexed: 12/29/2022] Open
Abstract
Death receptors are members of the tumor necrosis factor receptor superfamily involved in the extrinsic apoptotic pathway. Lifeguard (LFG) is a death receptor antagonist mainly expressed in the nervous system that specifically blocks Fas ligand (FasL)-induced apoptosis. To investigate its mechanism of action, we studied its subcellular localization and its interaction with members of the Bcl-2 family proteins. We performed an analysis of LFG subcellular localization in murine cortical neurons and found that LFG localizes mainly to the ER and Golgi. We confirmed these results with subcellular fractionation experiments. Moreover, we show by co-immunoprecipitation experiments that LFG interacts with Bcl-XL and Bcl-2, but not with Bax or Bak, and this interaction likely occurs in the endoplasmic reticulum. We further investigated the relationship between LFG and Bcl-XL in the inhibition of apoptosis and found that LFG protects only type II apoptotic cells from FasL-induced death in a Bcl-XL dependent manner. The observation that LFG itself is not located in mitochondria raises the question as to whether LFG in the ER participates in FasL-induced death. Indeed, we investigated the degree of calcium mobilization after FasL stimulation and found that LFG inhibits calcium release from the ER, a process that correlates with LFG blockage of cytochrome c release to the cytosol and caspase activation. On the basis of our observations, we propose that there is a required step in the induction of type II apoptotic cell death that involves calcium mobilization from the ER and that this step is modulated by LFG.
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Affiliation(s)
- Jorge Urresti
- From the Cell Signaling and Apoptosis Group and the Institut de Neurociències, Departament de Bioquímica i Biologia Molecular, Facultat de Medicina, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Marisol Ruiz-Meana
- Laboratory of Experimental Cardiology, Institut de Recerca de l'Hospital Universitari de la Vall d'Hebron, 08035 Barcelona, Spain
| | | | - Juan Carlos Arévalo
- the Department of Cell Biology and Pathology, Instituto de Neurociencias de Castilla y León, Universidad de Salamanca, Salamanca 37007, Spain, and the Institute of Biomedical Research of Salamanca, Salamanca 37007, Spain
| | - José Castellano
- Laboratory of Experimental Cardiology, Institut de Recerca de l'Hospital Universitari de la Vall d'Hebron, 08035 Barcelona, Spain
| | - Celia Fernández-Sanz
- Laboratory of Experimental Cardiology, Institut de Recerca de l'Hospital Universitari de la Vall d'Hebron, 08035 Barcelona, Spain
| | | | - Laura Planells-Ferrer
- From the Cell Signaling and Apoptosis Group and the Institut de Neurociències, Departament de Bioquímica i Biologia Molecular, Facultat de Medicina, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | | | | | | | - David García-Dorado
- Laboratory of Experimental Cardiology, Institut de Recerca de l'Hospital Universitari de la Vall d'Hebron, 08035 Barcelona, Spain
| | - Bruna Barneda-Zahonero
- From the Cell Signaling and Apoptosis Group and the Institut de Neurociències, Departament de Bioquímica i Biologia Molecular, Facultat de Medicina, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain,
| | - Joan X Comella
- From the Cell Signaling and Apoptosis Group and the Institut de Neurociències, Departament de Bioquímica i Biologia Molecular, Facultat de Medicina, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain,
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31
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Selyunin AS, Mukhopadhyay S. A Conserved Structural Motif Mediates Retrograde Trafficking of Shiga Toxin Types 1 and 2. Traffic 2015; 16:1270-87. [PMID: 26420131 DOI: 10.1111/tra.12338] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 09/15/2015] [Accepted: 09/15/2015] [Indexed: 12/20/2022]
Abstract
Shiga toxin-producing Escherichia coli (STEC) produce two types of Shiga toxin (STx): STx1 and STx2. The toxin A-subunits block protein synthesis, while the B-subunits mediate retrograde trafficking. STEC infections do not have definitive treatments, and there is growing interest in generating toxin transport inhibitors for therapy. However, a comprehensive understanding of the mechanisms of toxin trafficking is essential for drug development. While STx2 is more toxic in vivo, prior studies focused on STx1 B-subunit (STx1B) trafficking. Here, we show that, compared with STx1B, trafficking of the B-subunit of STx2 (STx2B) to the Golgi occurs with slower kinetics. Despite this difference, similar to STx1B, endosome-to-Golgi transport of STx2B does not involve transit through degradative late endosomes and is dependent on dynamin II, epsinR, retromer and syntaxin5. Importantly, additional experiments show that a surface-exposed loop in STx2B (β4-β5 loop) is required for its endosome-to-Golgi trafficking. We previously demonstrated that residues in the corresponding β4-β5 loop of STx1B are required for interaction with GPP130, the STx1B-specific endosomal receptor, and for endosome-to-Golgi transport. Overall, STx1B and STx2B share a common pathway and use a similar structural motif to traffic to the Golgi, suggesting that the underlying mechanisms of endosomal sorting may be evolutionarily conserved.
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Affiliation(s)
- Andrey S Selyunin
- Division of Pharmacology & Toxicology, College of Pharmacy; Institute for Cellular & Molecular Biology, Institute for Neuroscience, The University of Texas at Austin, Austin, TX 78712, USA
| | - Somshuvra Mukhopadhyay
- Division of Pharmacology & Toxicology, College of Pharmacy; Institute for Cellular & Molecular Biology, Institute for Neuroscience, The University of Texas at Austin, Austin, TX 78712, USA
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32
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Vieira DB, Thur K, Sultana S, Priestman D, van der Spoel AC. Verification and refinement of cellular glycosphingolipid profiles using HPLC. Biochem Cell Biol 2015; 93:581-6. [PMID: 26393781 DOI: 10.1139/bcb-2015-0074] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Glycosphingolipids (GSLs) are hybrid molecules consisting of the sphingolipid ceramide linked to a mono- or oligo-saccharide. In comparison to other membrane lipids, the family of GSLs stands out because of the extensive variation in the carbohydrate headgroup. GSLs are cell surface binding partners, in cis with growth factor receptors, and in trans with bacterial toxins and viruses, and are among the host-derived membrane components of viral particles, including those of HIV. In spite of their biological relevance, GSL profiles of commonly used cell lines have been analyzed to different degrees. Here, we directly compare the GSL complements from CHO-K1, COS-7, HeLa, HEK-293, HEPG2, Jurkat, and SH-SY5Y cells using an HPLC-based method requiring modest amounts of material. Compared to previous studies, the HPLC-based analyses provided more detailed information on the complexity of the cellular GSL complement, qualitatively as well as quantitatively. In particular for cells expressing multiple GSLs, we found higher numbers of GSL species, and different levels of abundance. Our study thus extends our knowledge of biologically relevant lipids in widely used cell lines.
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Affiliation(s)
- Douglas B Vieira
- a Atlantic Research Centre, Departments of Pediatrics and Biochemistry & Molecular Biology, Dalhousie University, Halifax, NS, Canada
| | - Karen Thur
- a Atlantic Research Centre, Departments of Pediatrics and Biochemistry & Molecular Biology, Dalhousie University, Halifax, NS, Canada
| | - Saki Sultana
- a Atlantic Research Centre, Departments of Pediatrics and Biochemistry & Molecular Biology, Dalhousie University, Halifax, NS, Canada
| | - David Priestman
- b Department of Pharmacology, University of Oxford, Oxford, OX1 3QT, UK
| | - Aarnoud C van der Spoel
- a Atlantic Research Centre, Departments of Pediatrics and Biochemistry & Molecular Biology, Dalhousie University, Halifax, NS, Canada
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Fragkostefanakis S, Simm S, Paul P, Bublak D, Scharf KD, Schleiff E. Chaperone network composition in Solanum lycopersicum explored by transcriptome profiling and microarray meta-analysis. PLANT, CELL & ENVIRONMENT 2015; 38:693-709. [PMID: 25124075 DOI: 10.1111/pce.12426] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 08/05/2014] [Indexed: 05/28/2023]
Abstract
Heat shock proteins (Hsps) are molecular chaperones primarily involved in maintenance of protein homeostasis. Their function has been best characterized in heat stress (HS) response during which Hsps are transcriptionally controlled by HS transcription factors (Hsfs). The role of Hsfs and Hsps in HS response in tomato was initially examined by transcriptome analysis using the massive analysis of cDNA ends (MACE) method. Approximately 9.6% of all genes expressed in leaves are enhanced in response to HS, including a subset of Hsfs and Hsps. The underlying Hsp-Hsf networks with potential functions in stress responses or developmental processes were further explored by meta-analysis of existing microarray datasets. We identified clusters with differential transcript profiles with respect to abiotic stresses, plant organs and developmental stages. The composition of two clusters points towards two major chaperone networks. One cluster consisted of constitutively expressed plastidial chaperones and other genes involved in chloroplast protein homeostasis. The second cluster represents genes strongly induced by heat, drought and salinity stress, including HsfA2 and many stress-inducible chaperones, but also potential targets of HsfA2 not related to protein homeostasis. This observation attributes a central regulatory role to HsfA2 in controlling different aspects of abiotic stress response and tolerance in tomato.
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Affiliation(s)
- Sotirios Fragkostefanakis
- Department of Biosciences, Molecular Cell Biology of Plants, Goethe University, 60438, Frankfurt/Main, Germany; Cluster of Excellence Frankfurt, Goethe University, 60438, Frankfurt/Main, Germany
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Yamaji T, Hanada K. Sphingolipid metabolism and interorganellar transport: localization of sphingolipid enzymes and lipid transfer proteins. Traffic 2014; 16:101-22. [PMID: 25382749 DOI: 10.1111/tra.12239] [Citation(s) in RCA: 289] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 10/29/2014] [Accepted: 11/06/2014] [Indexed: 11/28/2022]
Abstract
In recent decades, many sphingolipid enzymes, sphingolipid-metabolism regulators and sphingolipid transfer proteins have been isolated and characterized. This review will provide an overview of the intracellular localization and topology of sphingolipid enzymes in mammalian cells to highlight the locations where respective sphingolipid species are produced. Interestingly, three sphingolipids that reside or are synthesized in cytosolic leaflets of membranes (ceramide, glucosylceramide and ceramide-1-phosphate) all have cytosolic lipid transfer proteins (LTPs). These LTPs consist of ceramide transfer protein (CERT), four-phosphate adaptor protein 2 (FAPP2) and ceramide-1-phosphate transfer protein (CPTP), respectively. These LTPs execute functions that affect both the location and metabolism of the lipids they bind. Molecular details describing the mechanisms of regulation of LTPs continue to emerge and reveal a number of critical processes, including competing phosphorylation and dephosphorylation reactions and binding interactions with regulatory proteins and lipids that influence the transport, organelle distribution and metabolism of sphingolipids.
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Affiliation(s)
- Toshiyuki Yamaji
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo, 162-8640, Japan
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Targeting cellular squalene synthase, an enzyme essential for cholesterol biosynthesis, is a potential antiviral strategy against hepatitis C virus. J Virol 2014; 89:2220-32. [PMID: 25473062 DOI: 10.1128/jvi.03385-14] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
UNLABELLED Hepatitis C virus (HCV) exploits host membrane cholesterol and its metabolism for progeny virus production. Here, we examined the impact of targeting cellular squalene synthase (SQS), the first committed enzyme for cholesterol biosynthesis, on HCV production. By using the HCV JFH-1 strain and human hepatoma Huh-7.5.1-derived cells, we found that the SQS inhibitors YM-53601 and zaragozic acid A decreased viral RNA, protein, and progeny production in HCV-infected cells without affecting cell viability. Similarly, small interfering RNA (siRNA)-mediated knockdown of SQS led to significantly reduced HCV production, confirming the enzyme as an antiviral target. A metabolic labeling study demonstrated that YM-53601 suppressed the biosynthesis of cholesterol and cholesteryl esters at antiviral concentrations. Unlike YM-53601, the cholesterol esterification inhibitor Sandoz 58-035 did not exhibit an antiviral effect, suggesting that biosynthesis of cholesterol is more important than that of cholesteryl esters for HCV production. YM-53601 inhibited transient replication of a JFH-1 subgenomic replicon and entry of JFH-1 pseudoparticles, suggesting that at least suppression of viral RNA replication and entry contributes to the antiviral effect of the drug. Collectively, our findings highlight the importance of the cholesterol biosynthetic pathway in HCV production and implicate SQS as a potential target for antiviral strategies against HCV. IMPORTANCE Hepatitis C virus (HCV) is known to be closely associated with host cholesterol and its metabolism throughout the viral life cycle. However, the impact of targeting cholesterol biosynthetic enzymes on HCV production is not fully understood. We found that squalene synthase, the first committed enzyme for cholesterol biosynthesis, is important for HCV production, and we propose this enzyme as a potential anti-HCV target. We provide evidence that synthesis of free cholesterol is more important than that of esterified cholesterol for HCV production, highlighting a marked free cholesterol dependency of HCV production. Our findings also offer a new insight into a role of the intracellular cholesterol pool that is coupled to its biosynthesis in the HCV life cycle.
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Genome-wide RNAi screen reveals a role for multipass membrane proteins in endosome-to-golgi retrieval. Cell Rep 2014; 9:1931-1945. [PMID: 25464851 PMCID: PMC4542293 DOI: 10.1016/j.celrep.2014.10.053] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 09/18/2014] [Accepted: 10/17/2014] [Indexed: 11/22/2022] Open
Abstract
Endosome-to-Golgi retrieval is an essential membrane trafficking pathway required for many important physiological processes and linked to neurodegenerative disease and infection by bacterial and viral pathogens. The prototypical cargo protein for this pathway is the cation-independent mannose 6-phosphate receptor (CIMPR), which delivers lysosomal hydrolases to endosomes. Efficient retrieval of CIMPR to the Golgi requires the retromer complex, but other aspects of the endosome-to-Golgi retrieval pathway are poorly understood. Employing an image-based antibody-uptake assay, we conducted a genome-wide RNAi loss-of-function screen for novel regulators of this trafficking pathway and report ∼90 genes that are required for endosome-to-Golgi retrieval of a CD8-CIMPR reporter protein. Among these regulators of endosome-to-Golgi retrieval are a number of multipass membrane-spanning proteins, a class of proteins often overlooked with respect to a role in membrane trafficking. We further demonstrate a role for three multipass membrane proteins, SFT2D2, ZDHHC5, and GRINA, in endosome-to-Golgi retrieval.
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Fielding CA, Aicheler R, Stanton RJ, Wang ECY, Han S, Seirafian S, Davies J, McSharry BP, Weekes MP, Antrobus PR, Prod'homme V, Blanchet FP, Sugrue D, Cuff S, Roberts D, Davison AJ, Lehner PJ, Wilkinson GWG, Tomasec P. Two novel human cytomegalovirus NK cell evasion functions target MICA for lysosomal degradation. PLoS Pathog 2014; 10:e1004058. [PMID: 24787765 PMCID: PMC4006889 DOI: 10.1371/journal.ppat.1004058] [Citation(s) in RCA: 111] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Accepted: 02/18/2014] [Indexed: 02/07/2023] Open
Abstract
NKG2D plays a major role in controlling immune responses through the regulation of natural killer (NK) cells, αβ and γδ T-cell function. This activating receptor recognizes eight distinct ligands (the MHC Class I polypeptide-related sequences (MIC) A andB, and UL16-binding proteins (ULBP)1-6) induced by cellular stress to promote recognition cells perturbed by malignant transformation or microbial infection. Studies into human cytomegalovirus (HCMV) have aided both the identification and characterization of NKG2D ligands (NKG2DLs). HCMV immediate early (IE) gene up regulates NKGDLs, and we now describe the differential activation of ULBP2 and MICA/B by IE1 and IE2 respectively. Despite activation by IE functions, HCMV effectively suppressed cell surface expression of NKGDLs through both the early and late phases of infection. The immune evasion functions UL16, UL142, and microRNA(miR)-UL112 are known to target NKG2DLs. While infection with a UL16 deletion mutant caused the expected increase in MICB and ULBP2 cell surface expression, deletion of UL142 did not have a similar impact on its target, MICA. We therefore performed a systematic screen of the viral genome to search of addition functions that targeted MICA. US18 and US20 were identified as novel NK cell evasion functions capable of acting independently to promote MICA degradation by lysosomal degradation. The most dramatic effect on MICA expression was achieved when US18 and US20 acted in concert. US18 and US20 are the first members of the US12 gene family to have been assigned a function. The US12 family has 10 members encoded sequentially through US12-US21; a genetic arrangement, which is suggestive of an 'accordion' expansion of an ancestral gene in response to a selective pressure. This expansion must have be an ancient event as the whole family is conserved across simian cytomegaloviruses from old world monkeys. The evolutionary benefit bestowed by the combinatorial effect of US18 and US20 on MICA may have contributed to sustaining the US12 gene family.
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Affiliation(s)
- Ceri A. Fielding
- Section of Medical Microbiology, Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Rebecca Aicheler
- Section of Medical Microbiology, Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Richard J. Stanton
- Section of Medical Microbiology, Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Eddie C. Y. Wang
- Section of Medical Microbiology, Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Song Han
- Section of Medical Microbiology, Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Sepehr Seirafian
- Section of Medical Microbiology, Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - James Davies
- Section of Medical Microbiology, Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Brian P. McSharry
- Section of Medical Microbiology, Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Michael P. Weekes
- Cambridge Institute for Medical Research (CIMR), Wellcome Trust/MRC Building, Addenbrooke's Hospital, Cambridge, United Kingdom
| | - P. Robin Antrobus
- Cambridge Institute for Medical Research (CIMR), Wellcome Trust/MRC Building, Addenbrooke's Hospital, Cambridge, United Kingdom
| | - Virginie Prod'homme
- Section of Medical Microbiology, Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Fabien P. Blanchet
- Section of Medical Microbiology, Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Daniel Sugrue
- Section of Medical Microbiology, Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Simone Cuff
- Section of Medical Microbiology, Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Dawn Roberts
- Section of Medical Microbiology, Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Andrew J. Davison
- MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Paul J. Lehner
- Cambridge Institute for Medical Research (CIMR), Wellcome Trust/MRC Building, Addenbrooke's Hospital, Cambridge, United Kingdom
| | - Gavin W. G. Wilkinson
- Section of Medical Microbiology, Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
- * E-mail:
| | - Peter Tomasec
- Section of Medical Microbiology, Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
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TMBIM protein family: ancestral regulators of cell death. Oncogene 2014; 34:269-80. [DOI: 10.1038/onc.2014.6] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 12/27/2013] [Accepted: 01/02/2014] [Indexed: 12/13/2022]
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Yamaji T, Hanada K. Establishment of HeLa cell mutants deficient in sphingolipid-related genes using TALENs. PLoS One 2014; 9:e88124. [PMID: 24498430 PMCID: PMC3912166 DOI: 10.1371/journal.pone.0088124] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Accepted: 01/06/2014] [Indexed: 12/27/2022] Open
Abstract
Sphingolipids are essential components in eukaryotes and have various cellular functions. Recent developments in genome-editing technologies have facilitated gene disruption in various organisms and cell lines. We here show the disruption of various sphingolipid metabolic genes in human cervical carcinoma HeLa cells by using transcription activator-like effector nucleases (TALENs). A TALEN pair targeting the human CERT gene (alternative name COL4A3BP) encoding a ceramide transport protein induced a loss-of-function phenotype in more than 60% of HeLa cells even though the cell line has a pseudo-triploid karyotype. We have isolated several loss-of-function mutant clones for CERT, UGCG (encoding glucosylceramide synthase), and B4GalT5 (encoding the major lactosylceramide synthase), and also a CERT/UGCG double-deficient clone. Characterization of these clones supported previous proposals that CERT primarily contributes to the synthesis of SM but not GlcCer, and that B4GalT5 is the major LacCer synthase. These newly established sphingolipid-deficient HeLa cell mutants together with our previously established stable transfectants provide a ‘sphingolipid-modified HeLa cell panel,’ which will be useful to elucidate the functions of various sphingolipid species against essentially the same genomic background.
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Affiliation(s)
- Toshiyuki Yamaji
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
- * E-mail: (TY); (KH)
| | - Kentaro Hanada
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
- * E-mail: (TY); (KH)
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Weis C, Hückelhoven R, Eichmann R. LIFEGUARD proteins support plant colonization by biotrophic powdery mildew fungi. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:3855-67. [PMID: 23888068 PMCID: PMC3745739 DOI: 10.1093/jxb/ert217] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Pathogenic microbes manipulate eukaryotic cells during invasion and target plant proteins to achieve host susceptibility. BAX INHIBITOR-1 (BI-1) is an endoplasmic reticulum-resident cell death suppressor in plants and animals and is required for full susceptibility of barley to the barley powdery mildew fungus Blumeria graminis f.sp. hordei. LIFEGUARD (LFG) proteins resemble BI-1 proteins in terms of predicted membrane topology and cell-death-inhibiting function in metazoans, but display clear sequence-specific distinctions. This work shows that barley (Hordeum vulgare L.) and Arabidopsis thaliana genomes harbour five LFG genes, HvLFGa-HvLFGe and AtLFG1-AtLFG5, whose functions are largely uncharacterized. As observed for HvBI-1, single-cell overexpression of HvLFGa supports penetration success of B. graminis f.sp. hordei into barley epidermal cells, while transient-induced gene silencing restricts it. In penetrated barley epidermal cells, a green fluorescent protein-tagged HvLFGa protein accumulates at the site of fungal entry, around fungal haustoria and in endosomal or vacuolar membranes. The data further suggest a role of LFG proteins in plant-powdery mildew interactions in both monocot and dicot plants, because stable overexpression or knockdown of AtLFG1 or AtLFG2 also support or delay development of the powdery mildew fungus Erysiphe cruciferarum on the respective Arabidopsis mutants. Together, this work has identified new modulators of plant-powdery mildew interactions, and the data further support functional similarities between BI-1 and LFG proteins beyond cell death regulation.
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Affiliation(s)
| | | | - Ruth Eichmann
- * Present address: School of Life Sciences, University of Warwick, Gibbet Hill Campus, Coventry CV4 7AL, UK
- To whom correspondence should be addressed. E-mail:
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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]
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Cruz C, Cairrão E, Lourenço O, Almeida P, Verde I, Queiroz JA. Polyazamacrocycles as Potential Antitumor Agents for Human Prostate Cancer Cells. Chem Biol Drug Des 2013; 81:517-26. [DOI: 10.1111/cbdd.12098] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Liang YJ, Ding Y, Levery SB, Lobaton M, Handa K, Hakomori SI. Differential expression profiles of glycosphingolipids in human breast cancer stem cells vs. cancer non-stem cells. Proc Natl Acad Sci U S A 2013; 110:4968-73. [PMID: 23479608 PMCID: PMC3612608 DOI: 10.1073/pnas.1302825110] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Previous studies demonstrated that certain glycosphingolipids (GSLs) are involved in various cell functions, such as cell growth and motility. Recent studies showed changes in GSL expression during differentiation of human embryonic stem cells; however, little is known about expression profiles of GSLs in cancer stem cells (CSCs). CSCs are a small subpopulation in cancer and are proposed as cancer-initiating cells, have been shown to be resistant to numerous chemotherapies, and may cause cancer recurrence. Here, we analyzed GSLs expressed in human breast CSCs by applying a CSC model induced through epithelial-mesenchymal transition, using mass spectrometry, TLC immunostaining, and cell staining. We found that (i) Fuc-(n)Lc4Cer and Gb3Cer were drastically reduced in CSCs, whereas GD2, GD3, GM2, and GD1a were greatly increased in CSCs; (ii) among various glycosyltransferases tested, mRNA levels for ST3GAL5, B4GALNT1, ST8SIA1, and ST3GAL2 were increased in CSCs, which could explain the increased expression of GD3, GD2, GM2, and GD1a in CSCs; (iii) the majority of GD2+ cells and GD3+ cells were detected in the CD44(hi)/CD24(lo) cell population; and (iv) knockdown of ST8SIA1 and B4GALNT1 significantly reduced the expression of GD2 and GD3 and caused a phenotype change from CSC to a non-CSC, which was detected by reduced mammosphere formation and cell motility. Our results provide insight into GSL profiles in human breast CSCs, indicate a functional role of GD2 and GD3 in CSCs, and suggest a possible novel approach in targeting human breast CSCs to interfere with cancer recurrence.
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Affiliation(s)
- Yuh-Jin Liang
- Division of Biomembrane Research, Pacific Northwest Research Institute, Seattle, WA 98122
- Departments of Pathobiology and Global Health, University of Washington, Seattle, WA 98195
- Chang Gung Memorial Hospital at Linkou, Taoyuan 333, Taiwan; and
| | - Yao Ding
- Division of Biomembrane Research, Pacific Northwest Research Institute, Seattle, WA 98122
- Departments of Pathobiology and Global Health, University of Washington, Seattle, WA 98195
| | - Steven B. Levery
- Copenhagen Center for Glycomics and Department of Cellular and Molecular Medicine, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Marlin Lobaton
- Division of Biomembrane Research, Pacific Northwest Research Institute, Seattle, WA 98122
| | - Kazuko Handa
- Division of Biomembrane Research, Pacific Northwest Research Institute, Seattle, WA 98122
| | - Sen-itiroh Hakomori
- Division of Biomembrane Research, Pacific Northwest Research Institute, Seattle, WA 98122
- Departments of Pathobiology and Global Health, University of Washington, Seattle, WA 98195
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Tahiri F, Li Y, Hawke D, Ganiko L, Almeida I, Levery S, Zhou D. Lack of iGb3 and Isoglobo-Series Glycosphingolipids in Pig Organs Used for Xenotransplantation: Implications for Natural Killer T-Cell Biology. J Carbohydr Chem 2013; 32:44-67. [PMID: 23378701 DOI: 10.1080/07328303.2012.741637] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
α-1,3-Terminated galactose residues on glycoproteins and glycosphingolipids are recognized by natural anti-α-1,3-galactose antibodies in human serum and cause hyperacute rejection in pig-to-human xenotransplantation. Genetic depletion of α-1,3-galactosyltransferase-1 in pigs abolishes the hyperacute rejection reaction. However, the isoglobotriosylceramide (iGb3) synthase in pigs may produce additional α-1,3-terminated galactose residues on glycosphingolipids. In both α-1,3-galactosyltranserase-1 knockout mice and pigs, cytotoxic anti-α-1,3-galactose antibodies could be induced; thus, a paradox exists that anti-α-1,3-galactose antibodies are present in animals with functional iGb3 synthases. Furthermore, iGb3 has been found to be an endogenous antigen for natural killer T (NKT) cells, an innate type of lymphocyte that may initiate the adaptive immune responses. It has been reasoned that iGb3 may trigger the activation of NKT cells and cause the rejection of α-1,3-galactosyltransferase-1-deficient organs through the potent stimulatory effects of NKT cells on adaptive immune cells (see ref.([20])). In this study, we examined the expression of iGb3 and the isoglobo-series glycosphingolipids in pig organs, including the heart, liver, pancreas, and kidney, by ion-trap mass spectrometry, which has a sensitivity of measuring 1% iGb3 among Gb3 isomers, when 5 μg/mL of the total iGb3/Gb3 mixture is present (see ref.([35])). We did not detect iGb3 or other isoglobo-series glycosphingolipids in any of these organs, although they were readily detected in mouse and human thymus and dendritic cells. The lack of iGb3 and isoglobo-series glycosphingolipids in pig organs indicates that iGb3 is unlikely to be a relevant immune epitope in xenotransplantation.
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Affiliation(s)
- Fatima Tahiri
- MD Anderson Cancer Center, University of Texas, Houston, Texas, USA
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Abstract
Inhibiting the growth of tumor vasculature represents one of the relevant strategies against tumor progression. Between all the different pro-angiogenic molecular targets, plasma membrane glycosphingolipids have been under-investigated. In this present study, we explore the anti-angiogenic therapeutic advantage of a tumor immunotherapy targeting the globotriaosylceramide Gb3. In this purpose, a monoclonal antibody against Gb3, named 3E2 was developed and characterized. We first demonstrate that Gb3 is over-expressed in proliferative endothelial cells relative to quiescent cells. Then, we demonstrate that 3E2 inhibits endothelial cell proliferation in vitro by slowing endothelial cell proliferation and by increasing mitosis duration. Antibody 3E2 is further effective in inhibiting ex vivo angiogenesis in aorta ring assays. Moreover, 3E2 treatment inhibits NXS2 neuroblastoma development and liver metastases spreading in A/J mice. Immunohistology examination of the NXS2 metastases shows that only endothelial cells, but not cancer cells express Gb3. Finally, 3E2 treatment diminishes tumor vessels density, proving a specific therapeutic action of our monoclonal antibody to tumor vasculature. Our study demonstrates that Gb3 is a viable alternative target for immunotherapy and angiogenesis inhibition.
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Loizides-Mangold U, David FPA, Nesatyy VJ, Kinoshita T, Riezman H. Glycosylphosphatidylinositol anchors regulate glycosphingolipid levels. J Lipid Res 2012; 53:1522-34. [PMID: 22628614 DOI: 10.1194/jlr.m025692] [Citation(s) in RCA: 199] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Glycosylphosphatidylinositol (GPI) anchor biosynthesis takes place in the endoplasmic reticulum (ER). After protein attachment, the GPI anchor is transported to the Golgi where it undergoes fatty acid remodeling. The ER exit of GPI-anchored proteins is controlled by glycan remodeling and p24 complexes act as cargo receptors for GPI anchor sorting into COPII vesicles. In this study, we have characterized the lipid profile of mammalian cell lines that have a defect in GPI anchor biosynthesis. Depending on which step of GPI anchor biosynthesis the cells were defective, we observed sphingolipid changes predominantly for very long chain monoglycosylated ceramides (HexCer). We found that the structure of the GPI anchor plays an important role in the control of HexCer levels. GPI anchor-deficient cells that generate short truncated GPI anchor intermediates showed a decrease in very long chain HexCer levels. Cells that synthesize GPI anchors but have a defect in GPI anchor remodeling in the ER have a general increase in HexCer levels. GPI-transamidase-deficient cells that produce no GPI-anchored proteins but generate complete free GPI anchors had unchanged levels of HexCer. In contrast, sphingomyelin levels were mostly unaffected. We therefore propose a model in which the transport of very long chain ceramide from the ER to Golgi is regulated by the transport of GPI anchor molecules.
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Affiliation(s)
- Ursula Loizides-Mangold
- Department of Biochemistry, NCCR Chemical Biology, University of Geneva, CH-1211 Geneva, Switzerland
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47
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TMBIM3/GRINA is a novel unfolded protein response (UPR) target gene that controls apoptosis through the modulation of ER calcium homeostasis. Cell Death Differ 2012; 19:1013-26. [PMID: 22240901 DOI: 10.1038/cdd.2011.189] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Transmembrane BAX inhibitor motif-containing (TMBIM)-6, also known as BAX-inhibitor 1 (BI-1), is an anti-apoptotic protein that belongs to a putative family of highly conserved and poorly characterized genes. Here we report the function of TMBIM3/GRINA in the control of cell death by endoplasmic reticulum (ER) stress. Tmbim3 mRNA levels are strongly upregulated in cellular and animal models of ER stress, controlled by the PERK signaling branch of the unfolded protein response. TMBIM3/GRINA synergies with TMBIM6/BI-1 in the modulation of ER calcium homeostasis and apoptosis, associated with physical interactions with inositol trisphosphate receptors. Loss-of-function studies in D. melanogaster demonstrated that TMBIM3/GRINA and TMBIM6/BI-1 have synergistic activities against ER stress in vivo. Similarly, manipulation of TMBIM3/GRINA levels in zebrafish embryos revealed an essential role in the control of apoptosis during neuronal development and in experimental models of ER stress. These findings suggest the existence of a conserved group of functionally related cell death regulators across species beyond the BCL-2 family of proteins operating at the ER membrane.
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48
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Takematsu H, Yamamoto H, Naito-Matsui Y, Fujinawa R, Tanaka K, Okuno Y, Tanaka Y, Kyogashima M, Kannagi R, Kozutsumi Y. Quantitative transcriptomic profiling of branching in a glycosphingolipid biosynthetic pathway. J Biol Chem 2011; 286:27214-24. [PMID: 21665948 DOI: 10.1074/jbc.m111.234526] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Cellular biosynthesis of macromolecules often involves highly branched enzyme pathways, thus cellular regulation of such pathways could be rather difficult. To understand the regulatory mechanism, a systematic approach could be useful. We genetically analyzed a branched biosynthetic pathway for glycosphingolipid (GSL) GM1 using correlation index-based responsible enzyme gene screening (CIRES), a novel quantitative phenotype-genotype correlation analysis. CIRES utilizes transcriptomic profiles obtained from multiple cells. Among a panel of B cell lines, expression of GM1 was negatively correlated with and suppressed by gene expression of CD77 synthase (CD77Syn), whereas no significant positive correlation was found for enzymes actually biosynthesizing GM1. Unexpectedly, a GM1-suppressive phenotype was also observed in the expression of catalytically inactive CD77Syn, ruling out catalytic consumption of lactosylceramide (LacCer) as the main cause for such negative regulation. Rather, CD77Syn seemed to limit other branching reaction(s) by targeting LacCer synthase (LacCerSyn), a proximal enzyme in the pathway, because they were closely localized in the Golgi apparatus and formed a complex. Moreover, turnover of LacCerSyn was accelerated upon CD77Syn expression to globally change the GSL species expressed. Collectively, these data suggest that transcriptomic assessment of macromolecule biosynthetic pathways can disclose a global regulatory mechanism(s) even when unexpected.
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Affiliation(s)
- Hiromu Takematsu
- Laboratory of Membrane Biochemistry and Biophysics, Graduate School of Biostudies, Kyoto University, Sakyo, Kyoto 606-8501, Japan.
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49
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Abstract
Glycosylation is a very common modification of protein and lipid, and most glycosylation reactions occur in the Golgi. Although the transfer of initial sugar(s) to glycoproteins or glycolipids occurs in the ER or on the ER membrane, the subsequent addition of the many different sugars that make up a mature glycan is accomplished in the Golgi. Golgi membranes are studded with glycosyltransferases, glycosidases, and nucleotide sugar transporters arrayed in a generally ordered manner from the cis-Golgi to the trans-Golgi network (TGN), such that each activity is able to act on specific substrate(s) generated earlier in the pathway. The spectrum of glycosyltransferases and other activities that effect glycosylation may vary with cell type, and thus the final complement of glycans on glycoconjugates is variable. In addition, glycan synthesis is affected by Golgi pH, the integrity of Golgi peripheral membrane proteins, growth factor signaling, Golgi membrane dynamics, and cellular stress. Knowledge of Golgi glycosylation has fostered the development of assays to identify mechanisms of intracellular vesicular trafficking and facilitated glycosylation engineering of recombinant glycoproteins.
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Affiliation(s)
- Pamela Stanley
- Department of Cell Biology, Albert Einstein College of Medicine, New York, New York 10461, USA.
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50
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Maccioni HJF, Quiroga R, Ferrari ML. Cellular and molecular biology of glycosphingolipid glycosylation. J Neurochem 2011; 117:589-602. [PMID: 21371037 DOI: 10.1111/j.1471-4159.2011.07232.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Brain tissue is characterized by its high glycosphingolipid content, particularly those containing sialic acid (gangliosides). As a result of this observation, brain tissue was a focus for studies leading to the characterization of the enzymes participating in ganglioside biosynthesis, and their participation in driving the compositional changes that occur in glycolipid expression during brain development. Later on, this focus shifted to the study of cellular aspects of the synthesis, which lead to the identification of the site of synthesis in the neuronal soma and their axonal transport toward the periphery. In this review article, we will focus in subcellular aspects of the biosynthesis of glycosphingolipid oligosaccharides, particularly the mechanisms underlying the trafficking of glycosphingolipid glycosyltransferases from the endoplasmic reticulum to the Golgi, those that promote their retention in the Golgi and those that participate in their topological organization as part of the complex membrane bound machinery for the synthesis of glycosphingolipids.
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Affiliation(s)
- Hugo J F Maccioni
- Centro de Investigaciones en Química Biológica de Córdoba, CIQUIBIC (UNC-CONICET), Departamento de Química Biológica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina.
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