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Guo C, Wang W, Dong Y, Han Y. Identification of key immune-related genes and potential therapeutic drugs in diabetic nephropathy based on machine learning algorithms. BMC Med Genomics 2024; 17:220. [PMID: 39187837 PMCID: PMC11348758 DOI: 10.1186/s12920-024-01995-4] [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] [Received: 10/20/2023] [Accepted: 08/19/2024] [Indexed: 08/28/2024] Open
Abstract
BACKGROUND Diabetic nephropathy (DN) is a major contributor to chronic kidney disease. This study aims to identify immune biomarkers and potential therapeutic drugs in DN. METHODS We analyzed two DN microarray datasets (GSE96804 and GSE30528) for differentially expressed genes (DEGs) using the Limma package, overlapping them with immune-related genes from ImmPort and InnateDB. LASSO regression, SVM-RFE, and random forest analysis identified four hub genes (EGF, PLTP, RGS2, PTGDS) as proficient predictors of DN. The model achieved an AUC of 0.995 and was validated on GSE142025. Single-cell RNA data (GSE183276) revealed increased hub gene expression in epithelial cells. CIBERSORT analysis showed differences in immune cell proportions between DN patients and controls, with the hub genes correlating positively with neutrophil infiltration. Molecular docking identified potential drugs: cysteamine, eltrombopag, and DMSO. And qPCR and western blot assays were used to confirm the expressions of the four hub genes. RESULTS Analysis found 95 and 88 distinctively expressed immune genes in the two DN datasets, with 14 consistently differentially expressed immune-related genes. After machine learning algorithms, EGF, PLTP, RGS2, PTGDS were identified as the immune-related hub genes associated with DN. In addition, the mRNA and protein levels of them were obviously elevated in HK-2 cells treated with glucose for 24 h, as well as their mRNA expressions in kidney tissues of mice with DN. CONCLUSION This study identified 4 hub immune-related genes (EGF, PLTP, RGS2, PTGDS), as well as their expression profiles and the correlation with immune cell infiltration in DN.
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Affiliation(s)
- Chang Guo
- The Second Affiliated Hospital of Harbin Medical University, 246 Xuefu Road, Nangang District, Harbin, 10086, China.
| | - Wei Wang
- The Second Affiliated Hospital of Harbin Medical University, 246 Xuefu Road, Nangang District, Harbin, 10086, China
| | - Ying Dong
- The Second Affiliated Hospital of Harbin Medical University, 246 Xuefu Road, Nangang District, Harbin, 10086, China
| | - Yubing Han
- The Second Affiliated Hospital of Harbin Medical University, 246 Xuefu Road, Nangang District, Harbin, 10086, China
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2
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Shah N. Proteomics identify nuclear export as a targetable pathway in neuroblastoma: Comment on "XPO1 inhibition with selinexor synergizes with proteasome inhibition in neuroblastoma by targeting nuclear export of IκB". Transl Oncol 2021; 14:101150. [PMID: 34107420 PMCID: PMC8187248 DOI: 10.1016/j.tranon.2021.101150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 06/02/2021] [Indexed: 11/05/2022] Open
Abstract
Neuroblastoma (NBL) is an embryonal malignancy of childhood with poor outcomes for patient with high-risk disease. Multimodal treatment approaches have improved outcomes but at the cost of significant toxicity, and there is no durable therapeutic approach for relapsed disease. As NBL has no singular oncogenic driver, targeted therapeutic options have been limited. Galinski et al report the results of a proteomic screen of neuroblastomas and identify the nuclear export protein XPO1 as a protein that is preferentially expressed and located in neuroblast nuclei. XPO1 overexpression is associated with nuclear export of IκB and increased NF-κB activity, both of which can be abrogated in NBL cell lines with the XPO1 inhibitor Selinexor with or without the proteasome inhibitor bortezomib. This work highlights new strategies for therapeutic target identification and the novel identification of nuclear export as a targetable oncogenic pathway across malignancies.
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Affiliation(s)
- Nilay Shah
- Nationwide Children's Hospital, Department of Pediatric Hematology Oncology and Bone Marrow Transplants: Nationwide Children's Hospital Hematology Oncology & Blood and Marrow Transplant, USA
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3
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Ruhanen H, Haridas PAN, Jauhiainen M, Olkkonen VM. Angiopoietin-like protein 3, an emerging cardiometabolic therapy target with systemic and cell-autonomous functions. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1865:158791. [PMID: 32777482 DOI: 10.1016/j.bbalip.2020.158791] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/23/2020] [Accepted: 08/03/2020] [Indexed: 12/13/2022]
Abstract
Angiopoietin like protein 3 (ANGPTL3) is best known for its function as an inhibitor of lipoprotein and endothelial lipases. Due to the capacity of genetic or pharmacologic ANGPTL3 suppression to markedly reduce circulating lipoproteins, and the documented cardioprotection upon such suppression, ANGPTL3 has become an emerging therapy target for which both antibody and antisense oligonucleotide (ASO) therapeutics are being clinically tested. While the antibody is relatively selective for circulating ANGPTL3, the ASO also depletes the intra-hepatocellular protein, and there is emerging evidence for cell-autonomous functions of ANGPTL3 in the liver. These include regulation of hepatocyte glucose and fatty acid uptake, insulin sensitivity, LDL/VLDL remnant uptake, VLDL assembly/secretion, polyunsaturated fatty acid (PUFA) and PUFA-derived lipid mediator content, and gene expression. In this review we elaborate on (i) why ANGPTL3 is considered one of the most promising new cardiometabolic therapy targets, and (ii) the present evidences for its intra-hepatocellular or cell-autonomous functions.
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Affiliation(s)
- Hanna Ruhanen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland; Molecular and Integrative Biosciences, University of Helsinki, Finland
| | | | - Matti Jauhiainen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland
| | - Vesa M Olkkonen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland; Department of Anatomy, Faculty of Medicine, University of Helsinki, Finland.
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Chaudhuri R, Khanna K, Koundinya D, Pattnaik B, Vatsa D, Agrawal A, Ghosh B. Novel nuclear translocation of inositol polyphosphate 4-phosphatase is associated with cell cycle, proliferation and survival. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2018; 1865:S0167-4889(18)30188-5. [PMID: 30071275 DOI: 10.1016/j.bbamcr.2018.07.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 07/17/2018] [Indexed: 10/28/2022]
Abstract
Inositol polyphosphate 4 phosphatase type I enzyme (INPP4A) has a well-documented function in the cytoplasm where it terminates the phosphatidylinositol 3-kinase (PI 3-K) pathway by acting as a negative regulator. In this study, we demonstrate for the first time that INPP4A shuttles between the cytoplasm and the nucleus. Nuclear INPP4A is enzymatically active and in dynamic equilibrium between the nucleus and cytoplasm depending on the cell cycle stage, with highest amounts detected in the nucleus during the G0/G1 phase. Moreover, nuclear INPP4A is found to have direct proliferation suppressive activity. Cells constitutively overexpressing nuclear INPP4A exhibit massive apoptosis. In human tissues as well as cell lines, lower nuclear localization of INPP4A correlate with cancerous growth. Together, our findings suggest that nuclear compartmentalization of INPP4A may be a mechanism to regulate cell cycle progression, proliferation and apoptosis. Our results imply a role for nuclear-localized INPP4A in tumor suppression in humans.
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Affiliation(s)
- Rituparna Chaudhuri
- Molecular Immunogenetics Laboratory and Centre of Excellence for Translational Research in Asthma & Lung disease, CSIR-Institute of Genomics and Integrative Biology, Delhi 110007,India.; Academy of Scientific & Innovative Research, CSIR-Institute of Genomics and Integrative Biology, Delhi 110007, India
| | - Kritika Khanna
- Molecular Immunogenetics Laboratory and Centre of Excellence for Translational Research in Asthma & Lung disease, CSIR-Institute of Genomics and Integrative Biology, Delhi 110007,India.; Academy of Scientific & Innovative Research, CSIR-Institute of Genomics and Integrative Biology, Delhi 110007, India
| | - D Koundinya
- Molecular Immunogenetics Laboratory and Centre of Excellence for Translational Research in Asthma & Lung disease, CSIR-Institute of Genomics and Integrative Biology, Delhi 110007,India.; Academy of Scientific & Innovative Research, CSIR-Institute of Genomics and Integrative Biology, Delhi 110007, India
| | - Bijay Pattnaik
- Molecular Immunogenetics Laboratory and Centre of Excellence for Translational Research in Asthma & Lung disease, CSIR-Institute of Genomics and Integrative Biology, Delhi 110007,India.; Department of Pulmonary Medicine and Sleep Disorders, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India
| | - Damini Vatsa
- Molecular Immunogenetics Laboratory and Centre of Excellence for Translational Research in Asthma & Lung disease, CSIR-Institute of Genomics and Integrative Biology, Delhi 110007,India
| | - Anurag Agrawal
- Molecular Immunogenetics Laboratory and Centre of Excellence for Translational Research in Asthma & Lung disease, CSIR-Institute of Genomics and Integrative Biology, Delhi 110007,India.; Academy of Scientific & Innovative Research, CSIR-Institute of Genomics and Integrative Biology, Delhi 110007, India
| | - Balaram Ghosh
- Molecular Immunogenetics Laboratory and Centre of Excellence for Translational Research in Asthma & Lung disease, CSIR-Institute of Genomics and Integrative Biology, Delhi 110007,India.; Academy of Scientific & Innovative Research, CSIR-Institute of Genomics and Integrative Biology, Delhi 110007, India..
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Santos AL, Preta G. Lipids in the cell: organisation regulates function. Cell Mol Life Sci 2018; 75:1909-1927. [PMID: 29427074 PMCID: PMC11105414 DOI: 10.1007/s00018-018-2765-4] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 01/04/2018] [Accepted: 01/29/2018] [Indexed: 12/19/2022]
Abstract
Lipids are fundamental building blocks of all cells and play important roles in the pathogenesis of different diseases, including inflammation, autoimmune disease, cancer, and neurodegeneration. The lipid composition of different organelles can vary substantially from cell to cell, but increasing evidence demonstrates that lipids become organised specifically in each compartment, and this organisation is essential for regulating cell function. For example, lipid microdomains in the plasma membrane, known as lipid rafts, are platforms for concentrating protein receptors and can influence intra-cellular signalling. Lipid organisation is tightly regulated and can be observed across different model organisms, including bacteria, yeast, Drosophila, and Caenorhabditis elegans, suggesting that lipid organisation is evolutionarily conserved. In this review, we summarise the importance and function of specific lipid domains in main cellular organelles and discuss recent advances that investigate how these specific and highly regulated structures contribute to diverse biological processes.
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Affiliation(s)
- Ana L Santos
- Institut National de la Santé et de la Recherche Médicale, U1001 and Faculté de Médecine, Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Giulio Preta
- Institute of Biochemistry, Vilnius University, Sauletekio 7, LT-10257, Vilnius, Lithuania.
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Dong W, Gong H, Zhang G, Vuletic S, Albers J, Zhang J, Liang H, Sui Y, Zheng J. Lipoprotein lipase and phospholipid transfer protein overexpression in human glioma cells and their effect on cell growth, apoptosis, and migration. Acta Biochim Biophys Sin (Shanghai) 2017; 49:62-73. [PMID: 27864281 DOI: 10.1093/abbs/gmw117] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 10/26/2016] [Indexed: 01/01/2023] Open
Abstract
Glioma is one of the common tumors in brain. The expression level of lipoprotein lipase (LPL) or phospholipid transfer protein (PLTP) may influence glioma progression and its relationship with clinical and pathological parameters. The clinical significance of LPL or PLTP expression in glioma has not been established. In the present study, the LPL and PLTP levels in glioma tumors were investigated and the relationship between the LPL and PLTP level and the grade of malignant glioma was analyzed, with the aim to provide new ideas for the diagnosis and treatment of gliomas in clinical and basic research settings. LPL and PLTP mRNA and protein levels were significantly higher in Grade IV glioma than those in the lower grade tumors (P < 0.01). Double immunofluorescent staining showed that the levels of LPL and PLTP were significantly associated with the pathological grade of glioma (P = 0.005). The levels of LPL and PLTP were increased with the shortened survival of glioma patients (P < 0.001). Knockdown of LPL and PLTP led to decreased cell growth and migration but increased apoptosis in vitro Additionally, cell cycle-related cyclins and their partners were found to be down-regulated while cyclin-dependent kinase inhibitors p16, p21, and Rb were up-regulated. Furthermore, knockdown of LPL or PLTP resulted in the up-regulation of pro-apoptotic molecules and the down-regulation of anti-apoptotic molecules. Ablation of LPL or PLTP in U251 cells resulted in the down-regulation of epithelial mesenchymal transition markers and invasion molecules matrix metalloproteinases. LPL and PLTP appear to be novel glioma-associated proteins and play a role in the progression of human glioma.
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Affiliation(s)
- Weijiang Dong
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an 710061, China
| | - Huilin Gong
- Department of Pathology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China
| | - Guanjun Zhang
- Department of Pathology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China
| | - Simona Vuletic
- Northwest Lipid Metabolism and Diabetes Research Laboratories, Department of Medicine, School of Medicine, University of Washington, Seattle, 98109 WA
| | - John Albers
- Northwest Lipid Metabolism and Diabetes Research Laboratories, Department of Medicine, School of Medicine, University of Washington, Seattle, 98109 WA
| | - Jiaojiao Zhang
- Department of Pathology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China
| | - Hua Liang
- Department of Pathology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China
| | - Yanxia Sui
- Department of Pathology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China
| | - Jin Zheng
- Hospital of Nephrology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, China
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The binding capability of plasma phospholipid transfer protein, but not HDL pool size, is critical to repress LPS induced inflammation. Sci Rep 2016; 6:20845. [PMID: 26857615 PMCID: PMC4746621 DOI: 10.1038/srep20845] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 01/13/2016] [Indexed: 01/10/2023] Open
Abstract
Phospholipid transfer protein (PLTP) participates in high density lipoprotein (HDL) metabolism. Increased plasma PLTP activity was observed in lipopolysaccharide (LPS) triggered acute inflammatory diseases. This study aimed to determine the exact role of PLTP in LPS induced inflammation. HDL pool size was shrunk both in PLTP deficient mice (PLTP−/−) and PLTP transgenic mice (PLTP-Tg). PLTP displayed a strong protective effect on lethal endotoxemia in mice survival study. Furthermore, after LPS stimulation, the expression of pro-inflammatory cytokines were increased in bone marrow derived macrophage (BMDM) from PLTP−/−, while decreased in BMDM from PLTP-Tg compared with BMDM from wild-type mice (WT). Moreover, LPS induced nuclear factor kappa-B (NFκB) activation was enhanced in PLTP−/− BMDM or PLTP knockdown RAW264.7. Conversely, PLTP overexpression countered the NFκB activation in LPS challenged BMDM. Additionally, the activation of toll like receptor 4 (TLR4) induced by LPS showed no alteration in PLTP−/− BMDM. Finally, PLTP could bind to LPS, attenuate the pro-inflammatory effects of LPS, and improve the cell viability in vitro. To sum up, these findings elucidated that PLTP repressed LPS induced inflammation due to extracellular LPS binding capability, and the protective effects were not related to HDL pool size in mice.
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8
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Tong Y, Sun Y, Tian X, Zhou T, Wang H, Zhang T, Zhan R, Zhao L, Kuerban B, Li Z, Wang Q, Jin Y, Fan D, Guo X, Han H, Qin S, Chui D. Phospholipid transfer protein (PLTP) deficiency accelerates memory dysfunction through altering amyloid precursor protein (APP) processing in a mouse model of Alzheimer's disease. Hum Mol Genet 2015; 24:5388-403. [DOI: 10.1093/hmg/ddv262] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 07/06/2015] [Indexed: 01/19/2023] Open
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9
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Chirackal Manavalan AP, Kober A, Metso J, Lang I, Becker T, Hasslitzer K, Zandl M, Fanaee-Danesh E, Pippal JB, Sachdev V, Kratky D, Stefulj J, Jauhiainen M, Panzenboeck U. Phospholipid transfer protein is expressed in cerebrovascular endothelial cells and involved in high density lipoprotein biogenesis and remodeling at the blood-brain barrier. J Biol Chem 2014; 289:4683-98. [PMID: 24369175 PMCID: PMC3931031 DOI: 10.1074/jbc.m113.499129] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Phospholipid transfer protein (PLTP) is a key protein involved in biogenesis and remodeling of plasma HDL. Several neuroprotective properties have been ascribed to HDL. We reported earlier that liver X receptor (LXR) activation promotes cellular cholesterol efflux and formation of HDL-like particles in an established in vitro model of the blood-brain barrier (BBB) consisting of primary porcine brain capillary endothelial cells (pBCEC). Here, we report PLTP synthesis, regulation, and its key role in HDL metabolism at the BBB. We demonstrate that PLTP is highly expressed and secreted by pBCEC. In a polarized in vitro model mimicking the BBB, pBCEC secreted phospholipid-transfer active PLTP preferentially to the basolateral ("brain parenchymal") compartment. PLTP expression levels and phospholipid transfer activity were enhanced (up to 2.5-fold) by LXR activation using 24(S)-hydroxycholesterol (a cerebral cholesterol metabolite) or TO901317 (a synthetic LXR agonist). TO901317 administration elevated PLTP activity in BCEC from C57/BL6 mice. Preincubation of HDL3 with human plasma-derived active PLTP resulted in the formation of smaller and larger HDL particles and enhanced the capacity of the generated HDL particles to remove cholesterol from pBCEC by up to 3-fold. Pre-β-HDL, detected by two-dimensional crossed immunoelectrophoresis, was generated from HDL3 in pBCEC-derived supernatants, and their generation was markedly enhanced (1.9-fold) upon LXR activation. Furthermore, RNA interference-mediated PLTP silencing (up to 75%) reduced both apoA-I-dependent (67%) and HDL3-dependent (30%) cholesterol efflux from pBCEC. Based on these findings, we propose that PLTP is actively involved in lipid transfer, cholesterol efflux, HDL genesis, and remodeling at the BBB.
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Affiliation(s)
| | | | - Jari Metso
- the National Institute for Health and Welfare, Biomedicum, FI-00290 Helsinki, Finland, and
| | - Ingrid Lang
- Institute of Cell Biology, Histology, and Embryology, and
| | | | | | - Martina Zandl
- From the Institute of Pathophysiology and Immunology
| | | | | | - Vinay Sachdev
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria
| | - Dagmar Kratky
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria
| | - Jasminka Stefulj
- the Department of Molecular Biology, Ruder Boskovic Institute, 10000 Zagreb, Croatia
| | - Matti Jauhiainen
- the National Institute for Health and Welfare, Biomedicum, FI-00290 Helsinki, Finland, and
| | - Ute Panzenboeck
- From the Institute of Pathophysiology and Immunology, , To whom correspondence should be addressed: Institute of Pathophysiology and Immunology, Medical University of Graz, Heinrichstrasse 31a, 8010 Graz, Austria. Tel.: 43-316-3801955; Fax: 43-316-3809640; E-mail:
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Guo LL, Chen YJ, Wang T, An J, Wang CN, Shen YC, Yang T, Zhao L, Zuo QN, Zhang XH, Xu D, Wen FQ. Ox-LDL-induced TGF-β1 production in human alveolar epithelial cells: Involvement of the Ras/ERK/PLTP pathway. J Cell Physiol 2012; 227:3185-91. [DOI: 10.1002/jcp.24005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Saghizadeh M, Gribanova Y, Akhmedov NB, Farber DB. ZBED4, a cone and Müller cell protein in human retina, has a different cellular expression in mouse. Mol Vis 2011; 17:2011-8. [PMID: 21850176 PMCID: PMC3154125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Accepted: 07/18/2011] [Indexed: 11/17/2022] Open
Abstract
PURPOSE ZBED4, a protein in cones and Müller cells of human retina, may play important functions as a transcriptional activator of genes expressed in those cells or as a co-activator/repressor of their nuclear hormone receptors. To begin investigating these potential roles of ZBED4, we studied the developmental expression and localization of both the Zbed4 mRNA and protein of mouse retina. METHODS northern blots showed the presence of Zbed4 mRNA in retina and other mouse tissues, and western blots showed the nuclear and cytoplasmic expression of Zbed4 at different developmental times. Antibodies against Zbed4 and specific retinal cell markers were used for retinal immunohistochemistry. RESULTS Zbed4 mRNA was present at different levels in all the mouse tissues analyzed. The Zbed4 protein was barely detectable at embryonic day (E)14.5 but was clearly seen at E16 at both retinal outer and vitreal borders and throughout the retina by E18 and postnatal day 0 (P0). Thereafter, Zbed4 expression was more restricted to the inner retina. While ZBED4 is localized in cones and endfeet of Müller cells of human retina, in adult mouse retina Zbed4 is only detected in Müller cell endfeet and processes. The same localization of Zbed4 was observed in rat retina. In early development, Zbed4 is mainly present in the nuclear fraction of the mouse retina, and in adulthood it becomes more enriched in the cytoplasmic fraction. CONCLUSIONS The patterns of spatial and temporal expression of Zbed4 in the mouse retina suggest a possible involvement of this protein in retinal morphogenesis and Müller cell function.
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Affiliation(s)
- Mehrnoosh Saghizadeh
- Jules Stein Eye Institute, UCLA, Los Angeles, CA,Molecular Biology Institute, UCLA, Los Angeles, CA
| | | | | | - Debora B. Farber
- Jules Stein Eye Institute, UCLA, Los Angeles, CA,Molecular Biology Institute, UCLA, Los Angeles, CA
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Albers JJ, Vuletic S, Cheung MC. Role of plasma phospholipid transfer protein in lipid and lipoprotein metabolism. Biochim Biophys Acta Mol Cell Biol Lipids 2011; 1821:345-57. [PMID: 21736953 DOI: 10.1016/j.bbalip.2011.06.013] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Revised: 06/01/2011] [Accepted: 06/14/2011] [Indexed: 12/13/2022]
Abstract
The understanding of the physiological and pathophysiological role of PLTP has greatly increased since the discovery of PLTP more than a quarter of century ago. A comprehensive review of PLTP is presented on the following topics: PLTP gene organization and structure; PLTP transfer properties; different forms of PLTP; characteristics of plasma PLTP complexes; relationship of plasma PLTP activity, mass and specific activity with lipoprotein and metabolic factors; role of PLTP in lipoprotein metabolism; PLTP and reverse cholesterol transport; insights from studies of PLTP variants; insights of PLTP from animal studies; PLTP and atherosclerosis; PLTP and signal transduction; PLTP in the brain; and PLTP in human disease. PLTP's central role in lipoprotein metabolism and lipid transport in the vascular compartment has been firmly established. However, more studies are needed to further delineate PLTP's functions in specific tissues, such as the lung, brain and adipose tissue. Furthermore, the specific role that PLTP plays in human diseases, such as atherosclerosis, cancer, or neurodegenerative disease, remains to be clarified. Exciting directions for future research include evaluation of PLTP's physiological relevance in intracellular lipid metabolism and signal transduction, which undoubtedly will advance our knowledge of PLTP functions in health and disease. This article is part of a Special Issue entitled Advances in High Density Lipoprotein Formation and Metabolism: A Tribute to John F. Oram (1945-2010).
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Affiliation(s)
- John J Albers
- Northwest Lipid Metabolism and Diabetes Research Laboratories, Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington, 401 Queen Anne Ave N, Seattle, WA 98109, USA.
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Lee HK, Lee DS, Ryoo HM, Park JT, Park SJ, Bae HS, Cho MI, Park JC. The odontogenic ameloblast-associated protein (ODAM) cooperates with RUNX2 and modulates enamel mineralization via regulation of MMP-20. J Cell Biochem 2010; 111:755-67. [DOI: 10.1002/jcb.22766] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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14
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Dong W, Albers JJ, Vuletic S. Phospholipid transfer protein reduces phosphorylation of tau in human neuronal cells. J Neurosci Res 2009; 87:3176-85. [PMID: 19472218 DOI: 10.1002/jnr.22137] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Tau function is regulated by phosphorylation, and abnormal tau phosphorylation in neurons is one of the key processes associated with development of Alzheimer's disease and other tauopathies. In this study we provide evidence that phospholipid transfer protein (PLTP), one of the main lipid transfer proteins in the brain, significantly reduces levels of phosphorylated tau and increases levels of the inactive form of glycogen synthase kinase-3beta (GSK3 beta) in HCN2 cells. Furthermore, inhibition of phosphatidylinositol-3 kinase (PI3K) reversed the PLTP-induced increase in levels of GSK3 beta phosphorylated at serine 9 (pGSK3 beta(Ser9)) and partially reversed the PLTP-induced reduction in tau phosphorylation. We provide evidence that the PLTP-induced changes are not due to activation of Disabled-1 (Dab1), insofar as PLTP reduced levels of total and phosphorylated Dab1 in HCN2 cells. We have also shown that inhibition of tyrosine kinase activity of insulin receptor (IR) and/or insulin-like growth factor 1 (IGF1) receptor (IGFR) reverses the PLTP-induced increase in levels of phosphorylated Akt (pAkt(Thr308) and pAkt(Ser473)), suggesting that PLTP-mediated activation of the PI3K/Akt pathway is dependent on IR/IGFR receptor tyrosine kinase activity. Our study suggests that PLTP may be an important modulator of signal transduction pathways in human neurons.
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Affiliation(s)
- Weijiang Dong
- Northwest Lipid Metabolism and Diabetes Research Laboratories, University of Washington School of Medicine, Seattle, Washington 98109, USA
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