1
|
Villari G, Gioelli N, Gino M, Zhang H, Hodge K, Cordero F, Zanivan S, Zhu J, Serini G. Luminescent sensing of conformational integrin activation in living cells. Cell Rep 2025; 44:115319. [PMID: 39964812 PMCID: PMC11861568 DOI: 10.1016/j.celrep.2025.115319] [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: 05/14/2024] [Revised: 11/29/2024] [Accepted: 01/27/2025] [Indexed: 02/20/2025] Open
Abstract
Integrins are major receptors for secreted extracellular matrix, playing crucial roles in physiological and pathological contexts, such as angiogenesis and cancer. Regulation of the transition between inactive and active conformation is key for integrins to fulfill their functions, and pharmacological control of those dynamics may have therapeutic applications. We create and validate a prototypic luminescent β1 integrin activation sensor (β1IAS) by introducing a split luciferase into an activation reporting site between the βI and the hybrid domains. As a recombinant protein in both solution and living cells, β1IAS accurately reports β1 integrin activation in response to (bio)chemical and physical stimuli. A short interfering RNA (siRNA) high-throughput screening on live β1IAS knockin endothelial cells unveils hitherto unknown regulators of β1 integrin activation, such as β1 integrin inhibitors E3 ligase Pja2 and vascular endothelial growth factor B (VEGF-B). This split-luciferase-based strategy provides an in situ label-free measurement of integrin activation and may be applicable to other β integrins and receptors.
Collapse
Affiliation(s)
- Giulia Villari
- Department of Oncology, University of Torino School of Medicine, Candiolo, TO, Italy; Candiolo Cancer Institute - Fondazione del Piemonte per l'Oncologia (FPO) Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Candiolo, TO, Italy
| | - Noemi Gioelli
- Candiolo Cancer Institute - Fondazione del Piemonte per l'Oncologia (FPO) Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Candiolo, TO, Italy
| | - Marta Gino
- Department of Oncology, University of Torino School of Medicine, Candiolo, TO, Italy; Candiolo Cancer Institute - Fondazione del Piemonte per l'Oncologia (FPO) Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Candiolo, TO, Italy
| | - Heng Zhang
- Thrombosis and Hemostasis Program, Versiti Blood Research Institute, Milwaukee, WI, USA
| | - Kelly Hodge
- Cancer Research UK Scotland Institute, Glasgow, UK
| | | | - Sara Zanivan
- Cancer Research UK Scotland Institute, Glasgow, UK; School of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - Jieqing Zhu
- Thrombosis and Hemostasis Program, Versiti Blood Research Institute, Milwaukee, WI, USA; Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Guido Serini
- Department of Oncology, University of Torino School of Medicine, Candiolo, TO, Italy; Candiolo Cancer Institute - Fondazione del Piemonte per l'Oncologia (FPO) Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Candiolo, TO, Italy.
| |
Collapse
|
2
|
Xiao Y, He Z, Li W, Chen D, Niu X, Yang X, Zeng W, Wang M, Qian Y, Su Y, Luo F, Chen G, Liu J, Sui X, Zhou X, Gao Y. A covalent peptide-based lysosome-targeting protein degradation platform for cancer immunotherapy. Nat Commun 2025; 16:1388. [PMID: 39910101 PMCID: PMC11799215 DOI: 10.1038/s41467-025-56648-6] [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: 07/05/2024] [Accepted: 01/27/2025] [Indexed: 02/07/2025] Open
Abstract
The lysosome-targeting chimera (LYTAC) strategy provided a very powerful tool for the degradation of membrane proteins. However, the synthesis of LYTACs, antibody-small molecule conjugates, is challenging. The ability of antibody-based LYTACs to penetrate solid tumor is limited as well, especially to cross the blood-brain barrier (BBB). Here, we propose a covalent chimeric peptide-based targeted degradation platform (Pep-TACs) by introducing a long flexible aryl sulfonyl fluoride group, which allows proximity-enabled cross-linking upon binding with the protein of interest. The Pep-TACs platform facilitates the degradation of target proteins through the mechanism of recycling transferrin receptor (TFRC)-mediated lysosomal targeted endocytosis. Biological experiments demonstrate that covalent Pep-TACs can significantly degrade the expression of PD-L1 on tumor cells, dendritic cells and macrophages, especially under acidic conditions, and markedly enhance the function of T cells and tumor phagocytosis by macrophages. Furthermore, both in anti-PD-1-responsive and -resistant tumor models, the Pep-TACs exert significant anti-tumor immune response. It is noteworthy that Pep-TACs can cross the BBB and prolong the survival of mice with in situ brain tumor. As a proof-of-concept, this study introduces a modular TFRC-based covalent peptide degradation platform for the degradation of membrane protein, and especially for the immunotherapy of brain tumors.
Collapse
Affiliation(s)
- Youmei Xiao
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, Guangdong Province, China
| | - Zhuoying He
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, Guangdong Province, China
| | - Wanqiong Li
- The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, 518107, Guangdong Province, China
| | - Danhong Chen
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, Guangdong Province, China
| | - Xiaoshuang Niu
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, Guangdong Province, China
| | - Xin Yang
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, Guangdong Province, China
| | - Wenxuan Zeng
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, Guangdong Province, China
| | - Mengfan Wang
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, Guangdong Province, China
| | - Yuzhen Qian
- School of Life Sciences, Zhengzhou University, Zhengzhou, 450001, Henan Province, China
| | - Ye Su
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, Guangdong Province, China
| | - Feiyu Luo
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, Guangdong Province, China
| | - Guanyu Chen
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, Guangdong Province, China
| | - Juan Liu
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, Guangdong Province, China
| | - Xinghua Sui
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, Guangdong Province, China
| | - Xiuman Zhou
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, Guangdong Province, China.
| | - Yanfeng Gao
- School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, Guangdong Province, China.
| |
Collapse
|
3
|
Guo JL, Braun D, Fitzgerald GA, Hsieh YT, Rougé L, Litvinchuk A, Steffek M, Propson NE, Heffner CM, Discenza C, Han SJ, Rana A, Skuja LL, Lin BQ, Sun EW, Davis SS, Balasundar S, Becerra I, Dugas JC, Ha C, Hsiao-Nakamoto J, Huang F, Jain S, Kung JE, Liau NPD, Mahon CS, Nguyen HN, Nguyen N, Samaddar M, Shi Y, Tatarakis D, Tian Y, Zhu Y, Suh JH, Sandmann T, Calvert MEK, Arguello A, Kane LA, Lewcock JW, Holtzman DM, Koth CM, Di Paolo G. Decreased lipidated ApoE-receptor interactions confer protection against pathogenicity of ApoE and its lipid cargoes in lysosomes. Cell 2025; 188:187-206.e26. [PMID: 39532095 PMCID: PMC11724755 DOI: 10.1016/j.cell.2024.10.027] [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: 01/05/2024] [Revised: 07/08/2024] [Accepted: 10/15/2024] [Indexed: 11/16/2024]
Abstract
While apolipoprotein E (APOE) is the strongest genetic modifier for late-onset Alzheimer's disease (LOAD), the molecular mechanisms underlying isoform-dependent risk and the relevance of ApoE-associated lipids remain elusive. Here, we report that impaired low-density lipoprotein (LDL) receptor (LDLR) binding of lipidated ApoE2 (lipApoE2) avoids LDLR recycling defects observed with lipApoE3/E4 and decreases the uptake of cholesteryl esters (CEs), which are lipids linked to neurodegeneration. In human neurons, the addition of ApoE carrying polyunsaturated fatty acids (PUFAs)-CE revealed an allelic series (ApoE4 > ApoE3 > ApoE2) associated with lipofuscinosis, an age-related lysosomal pathology resulting from lipid peroxidation. Lipofuscin increased lysosomal accumulation of tau fibrils and was elevated in the APOE4 mouse brain with exacerbation by tau pathology. Intrahippocampal injection of PUFA-CE-lipApoE4 was sufficient to induce lipofuscinosis in wild-type mice. Finally, the protective Christchurch mutation also reduced LDLR binding and phenocopied ApoE2. Collectively, our data strongly suggest decreased lipApoE-LDLR interactions minimize LOAD risk by reducing the deleterious effects of endolysosomal targeting of ApoE and associated pathogenic lipids.
Collapse
Affiliation(s)
- Jing L Guo
- Denali Therapeutics Inc., South San Francisco, CA, USA.
| | - Dylan Braun
- Denali Therapeutics Inc., South San Francisco, CA, USA
| | | | | | - Lionel Rougé
- Denali Therapeutics Inc., South San Francisco, CA, USA
| | - Alexandra Litvinchuk
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
| | - Micah Steffek
- Denali Therapeutics Inc., South San Francisco, CA, USA
| | | | | | | | - Suk Ji Han
- Denali Therapeutics Inc., South San Francisco, CA, USA
| | - Anil Rana
- Denali Therapeutics Inc., South San Francisco, CA, USA
| | - Lukas L Skuja
- Denali Therapeutics Inc., South San Francisco, CA, USA
| | - Bi Qi Lin
- Denali Therapeutics Inc., South San Francisco, CA, USA
| | | | | | | | | | - Jason C Dugas
- Denali Therapeutics Inc., South San Francisco, CA, USA
| | - Connie Ha
- Denali Therapeutics Inc., South San Francisco, CA, USA
| | | | - Fen Huang
- Denali Therapeutics Inc., South San Francisco, CA, USA
| | - Shourya Jain
- Denali Therapeutics Inc., South San Francisco, CA, USA
| | | | | | | | | | - Nathan Nguyen
- Denali Therapeutics Inc., South San Francisco, CA, USA
| | | | - Yajuan Shi
- Denali Therapeutics Inc., South San Francisco, CA, USA
| | | | - Yuxi Tian
- Denali Therapeutics Inc., South San Francisco, CA, USA
| | - Yuda Zhu
- Denali Therapeutics Inc., South San Francisco, CA, USA
| | - Jung H Suh
- Denali Therapeutics Inc., South San Francisco, CA, USA
| | | | | | | | - Lesley A Kane
- Denali Therapeutics Inc., South San Francisco, CA, USA
| | | | - David M Holtzman
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
| | | | | |
Collapse
|
4
|
Ishemgulova A, Mukhamedova L, Trebichalská Z, Rájecká V, Payne P, Šmerdová L, Moravcová J, Hrebík D, Buchta D, Škubník K, Füzik T, Vaňáčová Š, Nováček J, Plevka P. Endosome rupture enables enteroviruses from the family Picornaviridae to infect cells. Commun Biol 2024; 7:1465. [PMID: 39511383 PMCID: PMC11543853 DOI: 10.1038/s42003-024-07147-9] [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: 04/02/2024] [Accepted: 10/24/2024] [Indexed: 11/15/2024] Open
Abstract
Membrane penetration by non-enveloped viruses is diverse and generally not well understood. Enteroviruses, one of the largest groups of non-enveloped viruses, cause diseases ranging from the common cold to life-threatening encephalitis. Enteroviruses enter cells by receptor-mediated endocytosis. However, how enterovirus particles or RNA genomes cross the endosome membrane into the cytoplasm remains unknown. Here we used cryo-electron tomography of infected cells to show that endosomes containing enteroviruses deform, rupture, and release the virus particles into the cytoplasm. Blocking endosome acidification with bafilomycin A1 reduced the number of particles that released their genomes, but did not prevent them from reaching the cytoplasm. Inhibiting post-endocytic membrane remodeling with wiskostatin promoted abortive enterovirus genome release in endosomes. The rupture of endosomes also occurs in control cells and after the endocytosis of very low-density lipoprotein. In summary, our results show that cellular membrane remodeling disrupts enterovirus-containing endosomes and thus releases the virus particles into the cytoplasm to initiate infection. Since the studied enteroviruses employ different receptors for cell entry but are delivered into the cytoplasm by cell-mediated endosome disruption, it is likely that most if not all enteroviruses, and probably numerous other viruses from the family Picornaviridae, can utilize endosome rupture to infect cells.
Collapse
Affiliation(s)
- Aygul Ishemgulova
- Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, 625 00, Czech Republic.
| | - Liya Mukhamedova
- Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, 625 00, Czech Republic
| | - Zuzana Trebichalská
- Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, 625 00, Czech Republic
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic
| | - Veronika Rájecká
- Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, 625 00, Czech Republic
| | - Pavel Payne
- Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, 625 00, Czech Republic
| | - Lenka Šmerdová
- Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, 625 00, Czech Republic
| | - Jana Moravcová
- Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, 625 00, Czech Republic
| | - Dominik Hrebík
- Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, 625 00, Czech Republic
| | - David Buchta
- Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, 625 00, Czech Republic
| | - Karel Škubník
- Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, 625 00, Czech Republic
| | - Tibor Füzik
- Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, 625 00, Czech Republic
| | - Štěpánka Vaňáčová
- Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, 625 00, Czech Republic
| | - Jiří Nováček
- Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, 625 00, Czech Republic
| | - Pavel Plevka
- Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, 625 00, Czech Republic.
| |
Collapse
|
5
|
Hao M, Sebag SC, Qian Q, Yang L. Lysosomal physiology and pancreatic lysosomal stress in diabetes mellitus. EGASTROENTEROLOGY 2024; 2:e100096. [PMID: 39512752 PMCID: PMC11542681 DOI: 10.1136/egastro-2024-100096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/15/2024]
Abstract
Endocrine and exocrine functions of the pancreas control nutritional absorption, utilisation and systemic metabolic homeostasis. Under basal conditions, the lysosome is pivotal in regulating intracellular organelles and metabolite turnover. In response to acute or chronic stress, the lysosome senses metabolic flux and inflammatory challenges, thereby initiating the adaptive programme to re-establish cellular homeostasis. A growing body of evidence has demonstrated the pathophysiological relevance of the lysosomal stress response in metabolic diseases in diverse sets of tissues/organs, such as the liver and the heart. In this review, we discuss the pathological relevance of pancreatic lysosome stress in diabetes mellitus. We begin by summarising lysosomal biology, followed by exploring the immune and metabolic functions of lysosomes and finally discussing the interplay between lysosomal stress and the pathogenesis of pancreatic diseases. Ultimately, our review aims to enhance our understanding of lysosomal stress in disease pathogenesis, which could potentially lead to the discovery of innovative treatment methods for these conditions.
Collapse
Affiliation(s)
- Meihua Hao
- Department of Anatomy and Cell Biology, Fraternal Order of Eagles Diabetes Research Center, Pappajohn Biomedical Institute, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | - Sara C Sebag
- Department of Anatomy and Cell Biology, Fraternal Order of Eagles Diabetes Research Center, Pappajohn Biomedical Institute, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | - Qingwen Qian
- Department of Anatomy and Cell Biology, Fraternal Order of Eagles Diabetes Research Center, Pappajohn Biomedical Institute, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | - Ling Yang
- Department of Anatomy and Cell Biology, Fraternal Order of Eagles Diabetes Research Center, Pappajohn Biomedical Institute, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| |
Collapse
|
6
|
Aldworth H, Hooper NM. Post-translational regulation of the low-density lipoprotein receptor provides new targets for cholesterol regulation. Biochem Soc Trans 2024; 52:431-440. [PMID: 38329179 PMCID: PMC10903450 DOI: 10.1042/bst20230918] [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: 11/14/2023] [Revised: 01/16/2024] [Accepted: 01/17/2024] [Indexed: 02/09/2024]
Abstract
The amount of the low-density lipoprotein receptor (LDLR) on the surface of hepatocytes is the primary determinant of plasma low-density lipoprotein (LDL)-cholesterol level. Although the synthesis and cellular trafficking of the LDLR have been well-documented, there is growing evidence of additional post-translational mechanisms that regulate or fine tune the surface availability of the LDLR, thus modulating its ability to bind and internalise LDL-cholesterol. Proprotein convertase subtilisin/kexin type 9 and the asialoglycoprotein receptor 1 both independently interact with the LDLR and direct it towards the lysosome for degradation. While ubiquitination by the E3 ligase inducible degrader of the LDLR also targets the receptor for lysosomal degradation, ubiquitination of the LDLR by a different E3 ligase, RNF130, redistributes the receptor away from the plasma membrane. The activity of the LDLR is also regulated by proteolysis. Proteolytic cleavage of the transmembrane region of the LDLR by γ-secretase destabilises the receptor, directing it to the lysosome for degradation. Shedding of the extracellular domain of the receptor by membrane-type 1 matrix metalloprotease and cleavage of the receptor in its LDL-binding domain by bone morphogenetic protein-1 reduces the ability of the LDLR to bind and internalise LDL-cholesterol at the cell surface. A better understanding of how the activity of the LDLR is regulated will not only unravel the complex biological mechanisms controlling LDL-cholesterol metabolism but also could help inform the development of alternative pharmacological intervention strategies for the treatment of hypercholesterolaemia.
Collapse
Affiliation(s)
- Harry Aldworth
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, U.K
| | - Nigel M. Hooper
- Division of Neuroscience, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, U.K
| |
Collapse
|
7
|
Yadav SPS, Yu A, Zhao J, Singh J, Kakkar S, Chakraborty S, Mechref Y, Molitoris B, Wagner MC. Glycosylation of a key cubilin Asn residue results in reduced binding to albumin. J Biol Chem 2022; 298:102371. [PMID: 35970386 PMCID: PMC9485058 DOI: 10.1016/j.jbc.2022.102371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 08/09/2022] [Accepted: 08/10/2022] [Indexed: 10/28/2022] Open
Abstract
Kidney disease often manifests with an increase in proteinuria, which can result from both glomerular and/or proximal tubule injury. The proximal tubules are the major site of protein and peptide endocytosis of the glomerular filtrate, and cubilin is the proximal tubule brush border membrane glycoprotein receptor that binds filtered albumin and initiates its processing in proximal tubules. Albumin also undergoes multiple modifications depending upon the physiologic state. We previously documented that carbamylated albumin had reduced cubilin binding, but the effects of cubilin modifications on binding albumin remain unclear. Here, we investigate the cubilin-albumin binding interaction to define the impact of cubilin glycosylation and map the key glycosylation sites while also targeting specific changes in a rat model of proteinuria. We identified a key Asn residue, N1285, that when glycosylated reduced albumin binding. In addition, we found a pH-induced conformation change may contribute to ligand release. To further define the albumin-cubilin binding site, we determined the solution structure of cubilin's albumin-binding domain, CUB7,8, using small-angle X-ray scattering and molecular modeling. We combined this information with mass spectrometry crosslinking experiments of CUB7,8 and albumin that provides a model of the key amino acids required for cubilin-albumin binding. Together, our data supports an important role for glycosylation in regulating the cubilin interaction with albumin, which is altered in proteinuria and provides new insight into the binding interface necessary for the cubilin-albumin interaction.
Collapse
Affiliation(s)
- Shiv Pratap Singh Yadav
- Nephrology Division, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Aiying Yu
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas, USA
| | - Jingfu Zhao
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas, USA
| | - Jasdeep Singh
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, New Delhi, India
| | - Saloni Kakkar
- CSIR-Institute of Microbial Technology, Chandigarh, India
| | | | - Yehia Mechref
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas, USA
| | - Bruce Molitoris
- Nephrology Division, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, USA; Department of Cellular & Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Mark C Wagner
- Nephrology Division, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, USA.
| |
Collapse
|
8
|
Ben-Naim L, Khalaila I, Papo N. Modifying pH-sensitive PCSK9/LDLR interactions as a strategy to enhance hepatic cell uptake of low-density lipoprotein cholesterol (LDL-C). Protein Eng Des Sel 2022; 35:6529797. [DOI: 10.1093/protein/gzab032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 11/29/2021] [Accepted: 12/08/2021] [Indexed: 11/14/2022] Open
Abstract
Abstract
LDL-receptor (LDLR)-mediated uptake of LDL-C into hepatocytes is impaired by lysosomal degradation of LDLR, which is promoted by proprotein convertase subtilisin/kexin type 9 (PCSK9). Cell surface binding of PCSK9 to LDLR produces a complex that translocates to an endosome, where the acidic pH strengthens the binding affinity of PCSK9 to LDLR, preventing LDLR recycling to the cell membrane. We present a new approach to inhibit PCSK9-mediated LDLR degradation, namely, targeting the PCSK9/LDLR interface with a PCSK9-antagonist, designated Flag-PCSK9PH, which prevents access of WT PCSK9 to LDLR. In HepG2 cells, Flag-PCSK9PH, a truncated version (residues 53–451) of human WT PCSK9, strongly bound LDLR at the neutral pH of the cell surface but dissociated from it in the endosome (acidic pH), allowing LDLR to exit the lysosomes intact and recycle to the cell membrane. Flag-PCSK9PH thus significantly enhanced cell-surface LDLR levels and the ability of LDLR to take up extracellular LDL-C.
Collapse
Affiliation(s)
- Lital Ben-Naim
- Avram and Stella Goldstein-Goren Department of Biotechnology Engineering, Faculty of Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Isam Khalaila
- Avram and Stella Goldstein-Goren Department of Biotechnology Engineering, Faculty of Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Niv Papo
- Avram and Stella Goldstein-Goren Department of Biotechnology Engineering, Faculty of Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
- The National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| |
Collapse
|
9
|
PCSK9 as a Target for Development of a New Generation of Hypolipidemic Drugs. Molecules 2022; 27:molecules27020434. [PMID: 35056760 PMCID: PMC8778893 DOI: 10.3390/molecules27020434] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 12/01/2021] [Accepted: 12/09/2021] [Indexed: 02/01/2023] Open
Abstract
PCSK9 has now become an important target to create new classes of lipid-lowering drugs. The prevention of its interaction with LDL receptors allows an increase in the number of these receptors on the surface of the cell membrane of hepatocytes, which leads to an increase in the uptake of cholesterol-rich atherogenic LDL from the bloodstream. The PCSK9 antagonists described in this review belong to different classes of compounds, may have a low molecular weight or belong to macromolecular structures, and also demonstrate different mechanisms of action. The mechanisms of action include preventing the effective binding of PCSK9 to LDLR, stimulating the degradation of PCSK9, and even blocking its transcription or transport to the plasma membrane/cell surface. Although several types of antihyperlipidemic drugs have been introduced on the market and are actively used in clinical practice, they are not without disadvantages, such as well-known side effects (statins) or high costs (monoclonal antibodies). Thus, there is still a need for effective cholesterol-lowering drugs with minimal side effects, preferably orally bioavailable. Low-molecular-weight PCSK9 inhibitors could be a worthy alternative for this purpose.
Collapse
|
10
|
Bashant MM, Mitchell SM, Hart LR, Lebedenko CG, Banerjee IA. In silico studies of interactions of peptide-conjugated cholesterol metabolites and betulinic acid with EGFR, LDR, and N-terminal fragment of CCKA receptors. J Mol Model 2021; 28:16. [PMID: 34961887 DOI: 10.1007/s00894-021-05007-5] [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: 07/05/2021] [Accepted: 12/14/2021] [Indexed: 11/25/2022]
Abstract
In this work, we designed three new ligands by conjugating cholesterol metabolites 3-hydroxy-5-cholestenoic acid (3-HC) and 3-oxo-4-cholestenoic acid (3-OC) and the natural tri-terpenoid betulinic acid with the tumor-targeting peptide YHWYGYTPQNVI. Molecular interactions with the unconjugated peptide and the conjugates were examined with three receptors that are commonly overexpressed in pancreatic adenocarcinoma cells using ligand docking and molecular dynamics. This study demonstrated the utility of the designed conjugates as a valuable scaffold for potentially targeting EGFR and LDLR receptors. Our results indicate that the conjugates showed strong binding affinities and formation of stable complexes with EGFR, while the unconjugated peptide, BT-peptide conjugate, an 3-HC-peptide conjugate showed the formation of fairly stable complexes with LDLR receptor. For EGFR, two receptor kinase domains were explored. Interactions with the N-terminal domain of CCKA-R were relatively weaker. For LDLR, binding occurred in the beta-propeller region. For the N-terminal fragment of CCKA-R, the conjugates induced significant conformational changes in the receptor. The molecular dynamic simulations for 100 ns demonstrate that BT-peptide conjugates and the unconjugated peptide had the highest binding and formed the most stable complexes with EGFR. RMSD and trajectory analyses indicate that these molecules transit to a dynamically stable configuration in most cases within 60 ns. NMA analysis indicated that amongst the conjugates that showed relatively higher interactions with the respective receptors, the highest potential for deformability was seen for the N-terminal-47 amino acid region of the CCKA-R receptor with and the lowest for the LDLR-receptor. Thus, the newly designed compounds may be evaluated in the future toward developing drug delivery materials for targeting tumor cells overexpressing LDLR or EGFR.
Collapse
Affiliation(s)
- Madeline M Bashant
- Department of Chemistry, Fordham University, 441 East Fordham Road, Bronx, NY, 10458, USA
| | - Saige M Mitchell
- Department of Chemistry, Fordham University, 441 East Fordham Road, Bronx, NY, 10458, USA
| | - Lucy R Hart
- Department of Chemistry, Fordham University, 441 East Fordham Road, Bronx, NY, 10458, USA
| | - Charlotta G Lebedenko
- Department of Chemistry, Fordham University, 441 East Fordham Road, Bronx, NY, 10458, USA
| | - Ipsita A Banerjee
- Department of Chemistry, Fordham University, 441 East Fordham Road, Bronx, NY, 10458, USA.
| |
Collapse
|
11
|
Zhang YM. Orosomucoid-like protein 3, rhinovirus and asthma. World J Crit Care Med 2021; 10:170-182. [PMID: 34616654 PMCID: PMC8462028 DOI: 10.5492/wjccm.v10.i5.170] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 04/16/2021] [Accepted: 08/23/2021] [Indexed: 02/06/2023] Open
Abstract
The genetic variants of orosomucoid-like protein 3 (ORMDL3) gene are associated with highly significant increases in the number of human rhinovirus (HRV)-induced wheezing episodes in children. Recent investigations have been focused on the mechanisms of ORMDL3 in rhinovirus infection for asthma and asthma exacerbations. ORMDL3 not only regulates major human rhinovirus receptor intercellular adhesion molecule 1 expression, but also plays pivotal roles in viral infection through metabolisms of ceramide and sphingosine-1-phosphate, endoplasmic reticulum (ER) stress, ER-Golgi interface and glycolysis. Research on the roles of ORMDL3 in HRV infection will lead us to identify new biomarkers and novel therapeutic targets in childhood asthma and viral induced asthma exacerbations.
Collapse
Affiliation(s)
- You-Ming Zhang
- Section of Genomic and Environmental Medicine, National Heart and Lung Institute, Molecular Genetics Group, Division of Respiratory Sciences, Imperial College London, London SW3 6LY, United Kingdom
| |
Collapse
|
12
|
Xie Y, Zhang X, Xu P, Zhao N, Zhao Y, Li Y, Hong Y, Peng M, Yuan K, Wan T, Sun R, Chen D, Xu L, Chen J, Guo H, Shan W, Li J, Li R, Xiong Y, Liu D, Wang Y, Liu G, Ye R, Liu X. Aberrant oligodendroglial LDL receptor orchestrates demyelination in chronic cerebral ischemia. J Clin Invest 2021; 131:128114. [PMID: 33141760 DOI: 10.1172/jci128114] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 10/29/2020] [Indexed: 01/09/2023] Open
Abstract
Oligodendrocytes express low-density lipoprotein receptor (LDLR) to endocytose cholesterol for the maintenance of adulthood myelination. However, the potential role of LDLR in chronic cerebral ischemia-related demyelination remains unclear. We used bilateral carotid artery stenosis (BCAS) to induce sustained cerebral ischemia in mice. This hypoxic-ischemic injury caused a remarkable decrease in oligodendroglial LDLR, with impaired oligodendroglial differentiation and survival. Oligodendroglial cholesterol levels, however, remained unchanged. Mouse miR-344e-3p and the human homolog miR-410-3p, 2 miRNAs directly targeting Ldlr, were identified in experimental and clinical leukoaraiosis and were thus implicated in the LDLR reduction. Lentiviral delivery of LDLR ameliorated demyelination following chronic cerebral ischemia. By contrast, Ldlr-/- mice displayed inadequate myelination in the corpus callosum. Ldlr-/- oligodendrocyte progenitor cells (OPCs) exhibited reduced ability to differentiate and myelinate axons in vitro. Transplantation with Ldlr-/- OPCs could not rescue the BCAS-induced demyelination. Such LDLR-dependent myelin restoration might involve a physical interaction of the Asn-Pro-Val-Tyr (NPVY) motif with the phosphotyrosine binding domain of Shc, which subsequently activated the MEK/ERK pathway. Together, our findings demonstrate that the aberrant oligodendroglial LDLR in chronic cerebral ischemia impairs myelination through intracellular signal transduction. Preservation of oligodendroglial LDLR may provide a promising approach to treat ischemic demyelination.
Collapse
Affiliation(s)
- Yi Xie
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Xiaohao Zhang
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Pengfei Xu
- Stroke Center & Department of Neurology, The Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| | - Nana Zhao
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Ying Zhao
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Yunzi Li
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Ye Hong
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Mengna Peng
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Kang Yuan
- Department of Neurology, Jinling Hospital, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Ting Wan
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Rui Sun
- Department of Neurology, Jinling Hospital, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Deyan Chen
- Center for Public Health Research, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Lili Xu
- Department of Neurology, Nanjing Brain Hospital Affiliated with Nanjing Medical University, Nanjing, Jiangsu, China
| | - Jingjing Chen
- Department of Neurology, Jinling Hospital, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Hongquan Guo
- Department of Neurology, Jinling Hospital, Southern Medical University, Nanjing, Jiangsu, China
| | - Wanying Shan
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Juanji Li
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Rongrong Li
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Yunyun Xiong
- China National Clinical Research Center for Neurological Diseases, Beijing, China.,Vascular Neurology, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Dezhi Liu
- Department of Neurology, Shuguang Hospital Affiliated with Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yuhui Wang
- Institute of Cardiovascular Sciences, School of Basic Medicine, Peking University Health Science Center, Beijing, China
| | - George Liu
- Institute of Cardiovascular Sciences, School of Basic Medicine, Peking University Health Science Center, Beijing, China
| | - Ruidong Ye
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China
| | - Xinfeng Liu
- Department of Neurology, Affiliated Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu, China.,Stroke Center & Department of Neurology, The Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China
| |
Collapse
|
13
|
Sigismund S, Lanzetti L, Scita G, Di Fiore PP. Endocytosis in the context-dependent regulation of individual and collective cell properties. Nat Rev Mol Cell Biol 2021; 22:625-643. [PMID: 34075221 DOI: 10.1038/s41580-021-00375-5] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/22/2021] [Indexed: 02/07/2023]
Abstract
Endocytosis allows cells to transport particles and molecules across the plasma membrane. In addition, it is involved in the termination of signalling through receptor downmodulation and degradation. This traditional outlook has been substantially modified in recent years by discoveries that endocytosis and subsequent trafficking routes have a profound impact on the positive regulation and propagation of signals, being key for the spatiotemporal regulation of signal transmission in cells. Accordingly, endocytosis and membrane trafficking regulate virtually every aspect of cell physiology and are frequently subverted in pathological conditions. Two key aspects of endocytic control over signalling are coming into focus: context-dependency and long-range effects. First, endocytic-regulated outputs are not stereotyped but heavily dependent on the cell-specific regulation of endocytic networks. Second, endocytic regulation has an impact not only on individual cells but also on the behaviour of cellular collectives. Herein, we will discuss recent advancements in these areas, highlighting how endocytic trafficking impacts complex cell properties, including cell polarity and collective cell migration, and the relevance of these mechanisms to disease, in particular cancer.
Collapse
Affiliation(s)
- Sara Sigismund
- IEO, European Institute of Oncology IRCCS, Milan, Italy.,Department of Oncology and Haemato-Oncology, Università degli Studi di Milano, Milan, Italy
| | - Letizia Lanzetti
- Department of Oncology, University of Torino Medical School, Torino, Italy.,Candiolo Cancer Institute, FPO - IRCCS, Candiolo, Torino, Italy
| | - Giorgio Scita
- Department of Oncology and Haemato-Oncology, Università degli Studi di Milano, Milan, Italy.,IFOM, the FIRC Institute of Molecular Oncology, Milan, Italy
| | - Pier Paolo Di Fiore
- IEO, European Institute of Oncology IRCCS, Milan, Italy. .,Department of Oncology and Haemato-Oncology, Università degli Studi di Milano, Milan, Italy.
| |
Collapse
|
14
|
Wu JH, Lv CF, Guo XJ, Zhang H, Zhang J, Xu Y, Wang J, Liu SY. Low Dose of Emodin Inhibits Hypercholesterolemia in a Rat Model of High Cholesterol. Med Sci Monit 2021; 27:e929346. [PMID: 34257265 PMCID: PMC8287934 DOI: 10.12659/msm.929346] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Emodin has been widely used in traditional Chinese medicine, but few studies have tried to understand the mechanism of its anti-hypercholesterolemic effect. MATERIAL AND METHODS To delineate the underlying pathways, high-cholesterol diet (HCD)-fed Sprague-Dawley rats were orally administrated emodin or the lipid-lowering medicine simvastatin. Emodin was administered at 10, 30, or 100 mg/kg, while simvastatin was administered at 10 mg/kg. Parameters measured included lipid profiles (serum total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol, aorta endothelium-dependent vasorelaxation in response to acetylcholine, and nitric oxide (NO) production. RT-qPCR and western blotting were performed to evaluate aortic endothelial nitric oxide synthase (eNOS), phosphorylated eNOS (p-eNOS), and hepatic LDL receptor (LDLR). Indices of liver and serum oxidation were also measured. RESULTS The atherogenic index was increased by the HCD but significantly reduced in all treatment groups. The HCD-fed experimental group treated with emodin at 10 mg/kg had significantly lower serum total-C and LDL-C and improved aorta vasorelaxation and enhanced NO production. Also, emodin significantly attenuated the lipid profiles and restored endothelial function, as reflected by upregulated expression of hepatic LDLR and p-eNOS, respectively. Furthermore, emodin at 10 mg/kg significantly enhanced superoxide dismutase activity, lowered the malondialdehyde level in both liver and serum, and enhanced catalase activity in serum. CONCLUSIONS The ability of emodin to inhibit hypercholesterolemia in HCD-fed rats was associated with lower serum total-C and LDL-C, restoration of aortic endothelial function, and improved antioxidant capacity. Low-dose emodin showed better protection of aortic endothelium and better antioxidant activity than did higher doses.
Collapse
Affiliation(s)
- Jian-Hong Wu
- Department of Clinical Laboratory, Shenzhen Nanshan Center for Chronic Disease Control, Shenzhen, Guangdong, China (mainland)
| | - Chun-Fang Lv
- Department of Clinical Laboratory, Shenzhen Nanshan Center for Chronic Disease Control, Shenzhen, Guangdong, China (mainland)
| | - Xu-Jun Guo
- Department of Clinical Laboratory, Shenzhen Nanshan Center for Chronic Disease Control, Shenzhen, Guangdong, China (mainland)
| | - Huan Zhang
- Department of Applied Biology and Chemical Technology, Hong Kong Polytechnic University, Hong Kong, Hong Kong
| | - Jinde Zhang
- Department of Clinical Laboratory, Shenzhen Nanshan Center for Chronic Disease Control, Shenzhen, Guangdong, China (mainland)
| | - Yangfeng Xu
- Department of Clinical Laboratory, Shenzhen Nanshan Center for Chronic Disease Control, Shenzhen, Guangdong, China (mainland)
| | - Jian Wang
- Department of Clinical Laboratory, Shenzhen Nanshan Center for Chronic Disease Control, Shenzhen, Guangdong, China (mainland)
| | - Sheng-Yuan Liu
- Department of Clinical Laboratory, Shenzhen Nanshan Center for Chronic Disease Control, Shenzhen, China (mainland)
| |
Collapse
|
15
|
Kim M, Bezprozvanny I. Differences in Recycling of Apolipoprotein E3 and E4-LDL Receptor Complexes-A Mechanistic Hypothesis. Int J Mol Sci 2021; 22:5030. [PMID: 34068576 PMCID: PMC8126166 DOI: 10.3390/ijms22095030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 05/05/2021] [Accepted: 05/07/2021] [Indexed: 12/13/2022] Open
Abstract
Apolipoprotein E (ApoE) is a protein that plays an important role in the transport of fatty acids and cholesterol and in cellular signaling. On the surface of the cells, ApoE lipoparticles bind to low density lipoprotein receptors (LDLR) that mediate the uptake of the lipids and downstream signaling events. There are three alleles of the human ApoE gene. Presence of ApoE4 allele is a major risk factor for developing Alzheimer's disease (AD) and other disorders late in life, but the mechanisms responsible for biological differences between different ApoE isoforms are not well understood. We here propose that the differences between ApoE isoforms can be explained by differences in the pH-dependence of the association between ApoE3 and ApoE4 isoforms and LDL-A repeats of LDLR. As a result, the following endocytosis ApoE3-associated LDLRs are recycled back to the plasma membrane but ApoE4-containing LDLR complexes are trapped in late endosomes and targeted for degradation. The proposed mechanism is predicted to lead to a reduction in steady-state surface levels of LDLRs and impaired cellular signaling in ApoE4-expressing cells. We hope that this proposal will stimulate experimental research in this direction that allows the testing of our hypothesis.
Collapse
Affiliation(s)
- Meewhi Kim
- Department of Physiology, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ilya Bezprozvanny
- Department of Physiology, UT Southwestern Medical Center, Dallas, TX 75390, USA
- Laboratory of Molecular Neurodegeneration, Peter the Great St. Petersburg State Polytechnic University, 195251 St. Petersburg, Russia
| |
Collapse
|
16
|
Elzi DJ, Bauta WE, Sanchez JR, Das T, Mogare S, Zannes Fatland P, Iza M, Pertsemlidis A, Rebel VI. Identification of a novel mechanism for meso-tetra (4-carboxyphenyl) porphyrin (TCPP) uptake in cancer cells. FASEB J 2021; 35:e21427. [PMID: 33629776 DOI: 10.1096/fj.202000197r] [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] [Received: 01/27/2020] [Revised: 01/13/2021] [Accepted: 01/22/2021] [Indexed: 01/23/2023]
Abstract
Porphyrins are used for cancer diagnostic and therapeutic applications, but the mechanism of how porphyrins accumulate in cancer cells remains elusive. Knowledge of how porphyrins enter cancer cells can aid the development of more accurate cancer diagnostics and therapeutics. To gain insight into porphyrin uptake mechanisms in cancer cells, we developed a flow cytometry assay to quantify cellular uptake of meso-tetra (4-carboxyphenyl) porphyrin (TCPP), a porphyrin that is currently being developed for cancer diagnostics. We found that TCPP enters cancer cells through clathrin-mediated endocytosis. The LDL receptor, previously implicated in the cellular uptake of other porphyrins, only contributes modestly to uptake. We report that TCPP instead binds strongly ( K D = 42 nM ) to CD320, the cellular receptor for cobalamin/transcobalamin II (Cbl/TCN2). Additionally, TCPP competes with Cbl/TCN2 for CD320 binding, suggesting that CD320 is a novel receptor for TCPP. Knockdown of CD320 inhibits TCPP uptake by up to 40% in multiple cancer cell lines, including lung, breast, and prostate cell lines, which supports our hypothesis that CD320 both binds to and transports TCPP into cancer cells. Our findings provide some novel insights into why porphyrins concentrate in cancer cells. Additionally, our study describes a novel function for the CD320 receptor which has been reported to transport only Cbl/TCN2 complexes.
Collapse
Affiliation(s)
- David J Elzi
- BioAffinity Technologies, Inc., San Antonio, TX, USA
| | | | | | - Trisha Das
- BioAffinity Technologies, Inc., San Antonio, TX, USA
| | - Shweta Mogare
- BioAffinity Technologies, Inc., San Antonio, TX, USA
| | | | - Moises Iza
- BioAffinity Technologies, Inc., San Antonio, TX, USA
| | - Alexander Pertsemlidis
- Department of Pediatrics, The University of Texas Health Science Center, San Antonio, TX, USA.,Department of Cell Systems & Anatomy, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.,Greehey Children's Cancer Research Institute, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.,Mays Cancer Center, UT Health San Antonio MD Anderson, San Antonio, TX, USA
| | - Vivienne I Rebel
- BioAffinity Technologies, Inc., San Antonio, TX, USA.,Department of Cell Systems & Anatomy, The University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| |
Collapse
|
17
|
LDL receptors and their role in targeted therapy for glioma: a review. Drug Discov Today 2021; 26:1212-1225. [PMID: 33609780 DOI: 10.1016/j.drudis.2021.02.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 01/15/2021] [Accepted: 02/06/2021] [Indexed: 11/22/2022]
Abstract
Gliomas are highly lethal forms of cancers occurring in the brain. Delivering the drugs into the brain is a major challenge to the treatment of gliomas because of the highly selectively permeable blood-brain barrier (BBB). Tapping the potential of receptor-mediated drug delivery systems using targeted nanoparticles (NPs) is a sought-after step forward toward successful glioma treatment. Several receptors are the focus of research for application in drug delivery. Low-density lipoprotein receptors (LDLR) are abundantly expressed in both healthy brains and diseased brains with a disrupted BBB. In this review, we discuss the LDLR and the types of NPs that have been used to target the brain via this receptor.
Collapse
|
18
|
The Cholesterol-Lowering Effect of Capsella Bursa-Pastoris Is Mediated via SREBP2 and HNF-1α-Regulated PCSK9 Inhibition in Obese Mice and HepG2 Cells. Foods 2021; 10:foods10020408. [PMID: 33673187 PMCID: PMC7918551 DOI: 10.3390/foods10020408] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 02/06/2021] [Accepted: 02/09/2021] [Indexed: 12/14/2022] Open
Abstract
The objective of the present study was to investigate the mechanism by which capsella bursa-pastoris ethanol extract (CBE), containing 17.5 milligrams of icaritin per kilogram of the extract, and icaritin, mediate hypocholesterolemic activity via the low-density lipoprotein receptor (LDLR) and pro-protein convertase subtilisin/kexin type 9 (PCSK9) in obese mice and HepG2 cells. CBE significantly attenuated serum total and LDL cholesterol levels in obese mice, which was associated with significantly decreased PCSK9 gene expression. HepG2 cells were cultured using delipidated serum (DLPS), and CBE significantly reduced PCSK9 and maintained the LDLR level. CBE co-treatment with rosuvastatin attenuated statin-mediated PCSK9 expression, and further increased LDLR. The icaritin contained in CBE decreased intracellular PCSK9 and LDLR levels by suppressing transcription factors SREBP2 and HNF-1α. Icaritin also significantly suppressed the extracellular PCSK9 level, which likely contributed to post-translational stabilization of LDLR in the HepG2 cells. PCSK9 inhibition by CBE is actively attributed to icaritin, and the use of CBE and icaritin could be an alternative therapeutic approach in the treatment of hypercholesterolemia.
Collapse
|
19
|
Zanka K, Kawaguchi Y, Okada Y, Nagaoka S. Epigallocatechin Gallate Induces Upregulation of LDL Receptor via the 67 kDa Laminin Receptor-Independent Pathway in HepG2 Cells. Mol Nutr Food Res 2020; 64:e1901036. [PMID: 31978263 DOI: 10.1002/mnfr.201901036] [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: 10/02/2019] [Revised: 12/27/2019] [Indexed: 12/14/2022]
Abstract
SCOPE Epigallocatechin gallate (EGCG), an active polyphenol in green tea, exhibits various physiological effects, including activation of low-density lipoprotein receptors (LDLR). The previous studies have suggested that EGCG activates LDLR via extracellular signal-regulated kinase (ERK) pathway in HepG2 cells. However, the detailed molecular mechanism remains unclear. Recently, 67 kDa laminin receptor (67LR) is identified as a receptor for EGCG. Therefore, this study aims to determine whether 67LR is involved in the mechanism of LDLR activation by EGCG. METHODS AND RESULTS EGCG induces upregulation of LDLR when 67LR is knocked down in HepG2 cells. Similar effect is observed after the cells are treated with 67LR monoclonal antibody. The loss of antiallergic effect following 67LR siRNA knockdown and 67LR antibody treatment confirms the results since the antiallergic effect of EGCG is known to be mediated by 67LR. CONCLUSION EGCG activates LDLR expression via 67LR-independent pathway in HepG2 cells.
Collapse
Affiliation(s)
- Kumiko Zanka
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Yuya Kawaguchi
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Yudai Okada
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | - Satoshi Nagaoka
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| |
Collapse
|
20
|
Kubota S, Tanaka Y, Nagaoka S. Ellagic acid affects mRNA expression levels of genes that regulate cholesterol metabolism in HepG2 cells. Biosci Biotechnol Biochem 2019; 83:952-959. [PMID: 30741106 DOI: 10.1080/09168451.2019.1576498] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Ellagic acid has been shown to improve cholesterol metabolism in animal studies, but the molecular mechanisms underlying this function have not been fully understood. We performed DNA microarray analysis to elucidate the effects of ellagic acid on cholesterol metabolism in HepG2 hepatocytes. This revealed that the expression levels of several genes related to cholesterol metabolism, including the low-density lipoprotein receptor (LDLR), were changed by ellagic acid treatment. Using a real-time PCR and immunoblot we confirmed that ellagic acid treatment up-regulated mRNA and protein expression level of the LDLR. Moreover, In the presence of 25 μM ellagic acid, extracellular apoB protein and MTP mRNA levels were significantly decreased. These findings indicate that ellagic acid improves cholesterol metabolism through the up-regulation of LDLR, down-regulation of MTP mRNA and reduces extracellular apoB levels. The ellagic acid-induced up-regulation of LDLR occurred via the extracellular signal-regulated kinase (ERK) signaling pathway in HepG2 hepatocytes. Abbreviations: LDLR: low-density lipoprotein receptor; apoB: apolipoprotein B; PKC: diacylglycerol-protein kinase C; MAPK: mitogen-activated protein kinase; ERK: p42/44 extracellular signal-regulated kinase; JNK: c-Jun N-terminal kinase; VLDLR: very low density lipoprotein receptor; PPARδ: peroxisome proliferator-activated receptor δ; SREBPs: sterol regulatory element-binding proteins; MTP: microsomal triacylglycerol transfer protein; LPDS: lipoprotein-deficient serum.
Collapse
Affiliation(s)
- Shizuka Kubota
- a Department of Applied Life Science, Faculty of Applied Biological Sciences , Gifu University , Gifu , Japan
| | - Yuma Tanaka
- a Department of Applied Life Science, Faculty of Applied Biological Sciences , Gifu University , Gifu , Japan
| | - Satoshi Nagaoka
- a Department of Applied Life Science, Faculty of Applied Biological Sciences , Gifu University , Gifu , Japan
| |
Collapse
|
21
|
The Cholesterol-Modulating Effect of Methanol Extract of Pigeon Pea ( Cajanus cajan (L.) Millsp.) Leaves on Regulating LDLR and PCSK9 Expression in HepG2 Cells. Molecules 2019; 24:molecules24030493. [PMID: 30704067 PMCID: PMC6385019 DOI: 10.3390/molecules24030493] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 01/22/2019] [Accepted: 01/29/2019] [Indexed: 12/13/2022] Open
Abstract
Pigeon pea (Cajanus cajan (L.) Millsp.) is a legume crop consumed as an indigenous vegetable in the human diet and a traditional medicinal plant with therapeutic properties. The current study highlights the cholesterol-modulating effect and underlying mechanisms of the methanol extract of Cajanus cajan L. leaves (MECC) in HepG2 cells. We found that MECC increased the LDLR expression, the cell-surface LDLR levels and the LDL uptake activity in HepG2 cells. We further demonstrated that MECC suppressed the proprotein convertase subtilisin/kexin type 9 (PCSK9) mRNA and protein expression, but not affected the expression of other cholesterol or lipid metabolism-related genes including inducible degrader of LDLR (IDOL), HMG-CoA reductase (HMGCR), fatty acid synthase (FASN), acetyl-CoA carboxylase (ACC1), and liver X receptor-α (LXR-α) in HepG2 cells. Furthermore, we demonstrated that MECC down-regulated the PCSK9 gene expression through reducing the amount of nuclear hepatocyte nuclear factor-1α (HNF-1α), a major transcriptional regulator for activation of PCSK9 promoter, but not that of nuclear sterol-responsive element binding protein-2 (SREBP-2) in HepG2 cells. Finally, we identified the cajaninstilbene acid, a main bioactive stilbene component in MECC, which significantly modulated the LDLR and PCSK9 expression in HepG2 cells. Our current data suggest that the cajaninstilbene acid may contribute to the hypocholesterolemic activity of Cajanus cajan L. leaves. Our findings support that the extract of Cajanus cajan L. leaves may serve as a cholesterol-lowering agent.
Collapse
|
22
|
Basnet S, Palmenberg AC, Gern JE. Rhinoviruses and Their Receptors. Chest 2019; 155:1018-1025. [PMID: 30659817 DOI: 10.1016/j.chest.2018.12.012] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 12/14/2018] [Accepted: 12/28/2018] [Indexed: 01/14/2023] Open
Abstract
Human rhinoviruses (RVs) are picornaviruses that can cause a variety of upper and lower respiratory tract illnesses, including the common cold, bronchitis, pneumonia, and exacerbations of chronic respiratory diseases such as asthma. There are currently > 160 known types of RVs classified into three species (A, B, and C) that use three different cellular membrane glycoproteins expressed in the respiratory epithelium to enter the host cell. These viral receptors are intercellular adhesion molecule 1 (used by the majority of RV-A and all RV-B types), low-density lipoprotein receptor family members (used by 12 RV-A types), and cadherin-related family member 3 (CDHR3; used by RV-C). RV-A and RV-B interactions with intercellular adhesion molecule 1 and low-density lipoprotein receptor glycoproteins are well defined and their cellular functions have been described, whereas the mechanisms of the RV-C interaction with CDHR3 and its cellular functions are being studied. A single nucleotide polymorphism (rs6967330) in CDHR3 increases cell surface expression of this protein and, as a result, also promotes RV-C infections and illnesses. There are currently no approved vaccines or antiviral therapies available to treat or prevent RV infections, which is a major unmet medical need. Understanding interactions between RV and cellular receptors could lead to new insights into the pathogenesis of respiratory illnesses as well as lead to new approaches to control respiratory illnesses caused by RV infections.
Collapse
Affiliation(s)
- Sarmila Basnet
- Department of Pediatrics, University of Wisconsin-Madison, Madison, WI.
| | - Ann C Palmenberg
- Institute of Molecular Virology, University of Wisconsin-Madison, Madison, WI
| | - James E Gern
- Department of Pediatrics, University of Wisconsin-Madison, Madison, WI
| |
Collapse
|
23
|
|
24
|
Abstract
Rhabdoviruses are enveloped viruses with a negative-sense single strand RNA genome and are widespread among a great variety of organisms. In their membrane, they have a single glycoprotein (G) that mediates both virus attachment to cellular receptors and fusion between viral and endosomal membranes allowing viral genome release in the cytoplasm. We present structural and cellular aspects of Rhabdovirus entry into their host cell with a focus on vesicular stomatitis virus (VSV) and rabies virus (RABV) for which the early events of the viral cycle have been extensively studied. Recent data have shown that the only VSV receptors are the members of the LDL-R family. This is in contrast with RABV for which multiple receptors belonging to unrelated families have been identified. Despite having different receptors, after attachment, rhabdovirus internalization occurs through clathrin-mediated endocytosis (CME) in an actin-dependent manner. There are still debates about the exact endocytic pathway of VSV in the cell and on RABV transport in the neuronal axon. In any case, fusion is triggered in the endosomal vesicle via a low-pH induced structural rearrangement of G from its pre- to its postfusion conformation. Vesiculovirus G is one of the best characterized fusion glycoproteins as the previously reported crystal structures of the pre- and postfusion states have been recently completed by those of intermediates during the structural transition. Understanding the entry pathway of rhabdoviruses may have strong impact in biotechnologies as, for example, VSV G is used for pseudotyping lentiviruses to promote efficient transduction, and VSV is a promising oncolytic virus.
Collapse
|
25
|
Validation of LDLr Activity as a Tool to Improve Genetic Diagnosis of Familial Hypercholesterolemia: A Retrospective on Functional Characterization of LDLr Variants. Int J Mol Sci 2018; 19:ijms19061676. [PMID: 29874871 PMCID: PMC6032215 DOI: 10.3390/ijms19061676] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Revised: 05/28/2018] [Accepted: 06/04/2018] [Indexed: 12/11/2022] Open
Abstract
Familial hypercholesterolemia (FH) is an autosomal dominant disorder characterized by high blood-cholesterol levels mostly caused by mutations in the low-density lipoprotein receptor (LDLr). With a prevalence as high as 1/200 in some populations, genetic screening for pathogenic LDLr mutations is a cost-effective approach in families classified as ‘definite’ or ‘probable’ FH and can help to early diagnosis. However, with over 2000 LDLr variants identified, distinguishing pathogenic mutations from benign mutations is a long-standing challenge in the field. In 1998, the World Health Organization (WHO) highlighted the importance of improving the diagnosis and prognosis of FH patients thus, identifying LDLr pathogenic variants is a longstanding challenge to provide an accurate genetic diagnosis and personalized treatments. In recent years, accessible methodologies have been developed to assess LDLr activity in vitro, providing experimental reproducibility between laboratories all over the world that ensures rigorous analysis of all functional studies. In this review we present a broad spectrum of functionally characterized missense LDLr variants identified in patients with FH, which is mandatory for a definite diagnosis of FH.
Collapse
|
26
|
Choi HK, Hwang JT, Nam TG, Kim SH, Min DK, Park SW, Chung MY. Welsh onion extract inhibits PCSK9 expression contributing to the maintenance of the LDLR level under lipid depletion conditions of HepG2 cells. Food Funct 2018; 8:4582-4591. [PMID: 29130084 DOI: 10.1039/c7fo00562h] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Statins mediate the transactivation of PCSK9, which in turn limits their cholesterol-lowering effects via LDL receptor (LDLR) degradation. The objective of the present study was to investigate the mechanism of action by which Welsh onion (Allium fistulosum L. [family Amaryllidaceae]) extract (WOE) regulates LDLR and PCSK9. HepG2 cells were cultured under lipid depletion conditions using a medium supplemented with delipidated serum (DLPS). WOE (50, 100, 200, and 400 μg ml-1) significantly attenuated the DLPS-mediated increases in LDLR, PCSK9, and SREBP2 gene expression. While WOE treatment maintained the DLPS-mediated increases in LDLR protein expression, it dose-dependently and significantly attenuated the DLPS-mediated increases in the protein content of PCSK9. The suppression of PCSK9 was associated with the WOE-mediated reductions in SREBP2, but not HNF1α. WOE also dose-dependently reduced PCSK9 protein expression that was otherwise markedly induced by concomitant statin treatment. WOE-mediated PCSK9 inhibition contributed to LDLR lysosomal degradation suppression, and subsequent LDLR protein stabilization. HPLC analysis indicated that WOE contains kaempferol, quercetin, ferulic acid, and p-coumaric acid. Kaempferol and p-coumaric acid contributed to the maintenance of LDLR expression by inhibiting PCSK9 in lipid depleted HepG2 cells. Altogether, these findings suggest that WOE inhibits PCSK9 transcription and protein expression via the reduction of SREBP2, and decreased PCSK9 further contributes to LDLR degradation prevention and LDLR protein stabilization under conditions of lipoprotein deficiency. The PCSK9 inhibition-mediated mechanism of WOE was likely attributed to the action of kaempferol and p-coumaric acid present in WOE.
Collapse
Affiliation(s)
- Hyo-Kyoung Choi
- Korea Food Research Institute, Seongnam City, Republic of Korea.
| | | | | | | | | | | | | |
Collapse
|
27
|
Hernández Flores TDJ, González García JR, Colima Fausto AG, Vázquez Cárdenas NA, Sánchez López Y, Zarate Morales CA, Magaña Torres MT. Screening of LDLR and APOB gene mutations in Mexican patients with homozygous familial hypercholesterolemia. J Clin Lipidol 2018; 12:693-701. [PMID: 29576406 DOI: 10.1016/j.jacl.2018.02.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 02/20/2018] [Accepted: 02/24/2018] [Indexed: 12/21/2022]
Abstract
BACKGROUND Familial hypercholesterolemia (FH) is an autosomal dominant disorder that causes accumulation of serum low-density lipoprotein cholesterol and premature cardiovascular disease. It is mainly related to mutations in the LDLR gene. Homozygous FH (HoFH) patients have the most severe form of the disease accounting for a worldwide prevalence of 1:1,000,000. In Mexico, at least 5 cases of HoFH have been reported. OBJECTIVE The aim of this study was to describe the clinical, biochemical, and molecular data observed in patients with HoFH phenotype. METHODS We included 13 patients, belonging to 11 families, with clinical and biochemical diagnoses suggestive of HoFH. Molecular analyses of the LDLR and APOB genes were performed by means of polymerase chain reaction followed by Sanger sequencing. RESULTS The causal mutation of HoFH was found in 8 of 11 unrelated patients. Excepting 1, all were true homozygotes. Six different variants in LDLR were identified: c.-139delCTCCCCCTGC, p.Glu140Lys, p.Asp360His, p.Asn405Lys, p.Ala755Glyfs*7, and p.Leu759Serfs*6. Of these, p.Asp360His and p.Asn405Lys were detected for the first time in Mexico; p.Leu759Serfs*6 showed to be the most frequent (43.7% of the alleles 7/16), and c.-139delCTCCCCCTGC is a new variant located in the promoter region. CONCLUSIONS This work increases knowledge of biochemical and genetic features in Mexican patients with HoFH. A novel mutation in the LDLR gene promoter was detected: c.-139delCTCCCCCTGC, which possibly inhibits its expression.
Collapse
Affiliation(s)
- Teresita De Jesús Hernández Flores
- División de Genética, Centro de Investigación Biomédica de Occidente, Instituto Mexicano del Seguro Social, Guadalajara, Jalisco, México; Doctorado en Genética Humana, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Jalisco, México
| | - Juan Ramón González García
- División de Genética, Centro de Investigación Biomédica de Occidente, Instituto Mexicano del Seguro Social, Guadalajara, Jalisco, México
| | - Ana Gabriela Colima Fausto
- División de Genética, Centro de Investigación Biomédica de Occidente, Instituto Mexicano del Seguro Social, Guadalajara, Jalisco, México; Doctorado en Genética Humana, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Jalisco, México
| | | | - Yoaly Sánchez López
- División de Genética, Centro de Investigación Biomédica de Occidente, Instituto Mexicano del Seguro Social, Guadalajara, Jalisco, México; Doctorado en Genética Humana, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Jalisco, México
| | - César Augusto Zarate Morales
- Hospital "Presidente Juárez" del Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado (ISSSTE), Oaxaca, Oax, México
| | - María Teresa Magaña Torres
- División de Genética, Centro de Investigación Biomédica de Occidente, Instituto Mexicano del Seguro Social, Guadalajara, Jalisco, México; Doctorado en Genética Humana, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Jalisco, México.
| |
Collapse
|
28
|
Wang S, Mao Y, Narimatsu Y, Ye Z, Tian W, Goth CK, Lira-Navarrete E, Pedersen NB, Benito-Vicente A, Martin C, Uribe KB, Hurtado-Guerrero R, Christoffersen C, Seidah NG, Nielsen R, Christensen EI, Hansen L, Bennett EP, Vakhrushev SY, Schjoldager KT, Clausen H. Site-specific O-glycosylation of members of the low-density lipoprotein receptor superfamily enhances ligand interactions. J Biol Chem 2018; 293:7408-7422. [PMID: 29559555 DOI: 10.1074/jbc.m117.817981] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 02/27/2018] [Indexed: 11/06/2022] Open
Abstract
The low-density lipoprotein receptor (LDLR) and related receptors are important for the transport of diverse biomolecules across cell membranes and barriers. Their functions are especially relevant for cholesterol homeostasis and diseases, including neurodegenerative and kidney disorders. Members of the LDLR-related protein family share LDLR class A (LA) repeats providing binding properties for lipoproteins and other biomolecules. We previously demonstrated that short linker regions between these LA repeats contain conserved O-glycan sites. Moreover, we found that O-glycan modifications at these sites are selectively controlled by the GalNAc-transferase isoform, GalNAc-T11. However, the effects of GalNAc-T11-mediated O-glycosylation on LDLR and related receptor localization and function are unknown. Here, we characterized O-glycosylation of LDLR-related proteins and identified conserved O-glycosylation sites in the LA linker regions of VLDLR, LRP1, and LRP2 (Megalin) from both cell lines and rat organs. Using a panel of gene-edited isogenic cell line models, we demonstrate that GalNAc-T11-mediated LDLR and VLDLR O-glycosylation is not required for transport and cell-surface expression and stability of these receptors but markedly enhances LDL and VLDL binding and uptake. Direct ELISA-based binding assays with truncated LDLR constructs revealed that O-glycosylation increased affinity for LDL by ∼5-fold. The molecular basis for this observation is currently unknown, but these findings open up new avenues for exploring the roles of LDLR-related proteins in disease.
Collapse
Affiliation(s)
- Shengjun Wang
- Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine and School of Dentistry, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Yang Mao
- Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine and School of Dentistry, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Yoshiki Narimatsu
- Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine and School of Dentistry, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Zilu Ye
- Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine and School of Dentistry, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Weihua Tian
- Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine and School of Dentistry, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Christoffer K Goth
- Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine and School of Dentistry, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Erandi Lira-Navarrete
- Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine and School of Dentistry, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Nis B Pedersen
- Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine and School of Dentistry, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Asier Benito-Vicente
- Biofisika Institute, Centro Superior de Investigaciones Cientificas (CSIC), Universidad del Pais Vasco/Euskal Herriko Unibertsitatea (UPV/EHU), and Departamento de Bioquimica, Universidad del Pais Vasco, 48080 Bilbao, Spain
| | - Cesar Martin
- Biofisika Institute, Centro Superior de Investigaciones Cientificas (CSIC), Universidad del Pais Vasco/Euskal Herriko Unibertsitatea (UPV/EHU), and Departamento de Bioquimica, Universidad del Pais Vasco, 48080 Bilbao, Spain
| | - Kepa B Uribe
- Biofisika Institute, Centro Superior de Investigaciones Cientificas (CSIC), Universidad del Pais Vasco/Euskal Herriko Unibertsitatea (UPV/EHU), and Departamento de Bioquimica, Universidad del Pais Vasco, 48080 Bilbao, Spain
| | - Ramon Hurtado-Guerrero
- The Institute for Biocomputation and Physics of Complex Systems (BIFI), University of Zaragoza, BIFI-Instituto de Química Física Rocasolano (IQFR), CSIC Joint Unit, Mariano Esquillor s/n, Campus Rio Ebro, 50009 Zaragoza, Spain
| | - Christina Christoffersen
- Department of Clinical Biochemistry, Rigshospitalet and Department of Biomedical Sciences, University of Copenhagen, Copenhagen 2100, Denmark
| | - Nabil G Seidah
- Clinical Research Institute of Montreal, University of Montreal, Montreal, Quebec H2W 1R7, Canada
| | - Rikke Nielsen
- Department of Biomedicine, Aarhus University, DK-8000 Aarhus, Denmark
| | | | - Lars Hansen
- Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine and School of Dentistry, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Eric P Bennett
- Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine and School of Dentistry, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Sergey Y Vakhrushev
- Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine and School of Dentistry, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Katrine T Schjoldager
- Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine and School of Dentistry, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark.
| | - Henrik Clausen
- Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine and School of Dentistry, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark.
| |
Collapse
|
29
|
Abstract
Vesicular stomatitis virus (VSV) is an oncolytic rhabdovirus and its glycoprotein G is widely used to pseudotype other viruses for gene therapy. Low-density lipoprotein receptor (LDL-R) serves as a major entry receptor for VSV. Here we report two crystal structures of VSV G in complex with two distinct cysteine-rich domains (CR2 and CR3) of LDL-R, showing that their binding sites on G are identical. We identify two basic residues on G, which are essential for its interaction with CR2 and CR3. Mutating these residues abolishes VSV infectivity even though VSV can use alternative receptors, indicating that all VSV receptors are members of the LDL-R family. Collectively, our data suggest that VSV G has specifically evolved to interact with receptor CR domains. These structural insights into the interaction between VSV G and host cell receptors provide a basis for the design of recombinant viruses with an altered tropism.
Collapse
|
30
|
Ce O, Rs P, Ab W, S D, Cj W, Qm M, D L. Potential Link Between Proprotein Convertase Subtilisin/Kexin Type 9 and Alzheimer's Disease. ACTA ACUST UNITED AC 2018; 1. [PMID: 32352077 DOI: 10.31531/2581-4745.1000106] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Alzheimer's disease [AD] is not only the most common neurodegenerative disease but is also currently incurable. Proprotein convertase subtilisin/kexin-9 [PCSK9] is an indirect regulator of plasma low density lipoprotein [LDL] levels controlling LDL receptor expression at the plasma membrane. PCSK9 also appears to regulate the development of glucose intolerance, insulin resistance, abdominal obesity, inflammation, and hypertension, conditions that have been identified as risk factors for AD. PCSK9 levels also depend on age, sex, and ethnic background, factors associated with AD. Herein, we will review indirect evidence that suggests a link between PCSK9 levels and AD.
Collapse
Affiliation(s)
- Oldham Ce
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise [BRITE], College of Arts and Sciences, North Carolina Central University, Durham, USA
| | - Powell Rs
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise [BRITE], College of Arts and Sciences, North Carolina Central University, Durham, USA
| | - Williams Ab
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise [BRITE], College of Arts and Sciences, North Carolina Central University, Durham, USA
| | - Dixon S
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise [BRITE], College of Arts and Sciences, North Carolina Central University, Durham, USA
| | - Wooten Cj
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise [BRITE], College of Arts and Sciences, North Carolina Central University, Durham, USA
| | - Melendez Qm
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise [BRITE], College of Arts and Sciences, North Carolina Central University, Durham, USA
| | - Lopez D
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise [BRITE], College of Arts and Sciences, North Carolina Central University, Durham, USA
| |
Collapse
|
31
|
Yang T, Williams BO. Low-Density Lipoprotein Receptor-Related Proteins in Skeletal Development and Disease. Physiol Rev 2017; 97:1211-1228. [PMID: 28615463 DOI: 10.1152/physrev.00013.2016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 03/07/2017] [Accepted: 03/15/2017] [Indexed: 02/06/2023] Open
Abstract
The identification of the low-density lipoprotein receptor (LDLR) provided a foundation for subsequent studies in lipoprotein metabolism, receptor-mediated endocytosis, and many other fundamental biological functions. The importance of the LDLR led to numerous studies that identified homologous molecules and ultimately resulted in the description of the LDL-receptor superfamily, a group of proteins that contain domains also found in the LDLR. Subsequent studies have revealed that members of the LDLR-related protein family play roles in regulating many aspects of signal transduction. This review is focused on the roles of selected members of this protein family in skeletal development and disease. We present background on the identification of this subgroup of receptors, discuss the phenotypes associated with alterations in their function in human patients and mouse models, and describe the current efforts to therapeutically target these proteins to treat human skeletal disease.
Collapse
Affiliation(s)
- Tao Yang
- Program in Skeletal Disease and Tumor Microenvironment, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, Michigan
| | - Bart O Williams
- Program in Skeletal Disease and Tumor Microenvironment, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, Michigan
| |
Collapse
|
32
|
Hypercholesterolemia: The role of PCSK9. Arch Biochem Biophys 2017; 625-626:39-53. [DOI: 10.1016/j.abb.2017.06.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 05/29/2017] [Accepted: 06/02/2017] [Indexed: 01/06/2023]
|
33
|
Sultan Alvi S, Ansari IA, Khan I, Iqbal J, Khan MS. Potential role of lycopene in targeting proprotein convertase subtilisin/kexin type-9 to combat hypercholesterolemia. Free Radic Biol Med 2017; 108:394-403. [PMID: 28412198 DOI: 10.1016/j.freeradbiomed.2017.04.012] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 03/18/2017] [Accepted: 04/12/2017] [Indexed: 11/23/2022]
Abstract
Proprotein convertase subtilisin/kexin type 9 (PCSK-9) is a serine protease of the proprotien convertase (PC) family that has profound effects on plasma low density lipoprotein cholesterol (LDL-C) levels, the major risk factor for coronary heart disease (CHD), through its ability to mediate LDL receptor (LDL-R) protein degradation and reduced recycling to the surface of hepatocytes. Thus, the current study was premeditated not only to evaluate the role of lycopene in targeting the inhibition of PCSK-9 via modulation of genes involved in cholesterol homeostasis in HFD rats but also to examine a correlation between HFD induced inflammatory cascades and subsequent regulation of PCSK-9 expression. Besides the effect of lycopene on hepatic PCSK-9 gene expression, PPI studies for PCSK-9-Lycopene complex and EGF-A of LDL-R were also performed via molecular informatics approach to assess the dual mode of action of lycopene in LDL-R recycling and increased removal of circulatory LDL-C. We for the first time deciphered that lycopene treatment significantly down-regulates the expression of hepatic PCSK-9 and HMGR, whereas, hepatic LDL-R expression was significantly up-regulated. Furthermore, lycopene ameliorated inflammation stimulated expression of PCSK-9 via suppressing the expression of inflammatory markers. The results from our molecular informatics studies confirmed that lycopene, while occupying the active site of PCSK-9 crystal structure, reduces the affinity of PCSK-9 to complex with EGF-A of LDL-R, whereas, atorvastatin makes PCSK-9-EGF-A complex formation more feasible than both of PCSK-9-EGF-A alone and Lycopene-PCSK-9-EGF-A complex. Based on above results, it can be concluded that lycopene exhibits potent hypolipidemic activities via molecular mechanisms that are either identical (HMGR inhibition) or distinct from that of statins (down-regulation of PCSK-9 mRNA synthesis). To the best of our knowledge, this is the first report that lycopene has this specific biological property. Being a natural, safer and alternative therapeutic agent, lycopene could be used as a complete regulator of cholesterol homeostasis and ASCVD.
Collapse
Affiliation(s)
- Sahir Sultan Alvi
- Clinical Biochemistry & Natural Product Research Lab., Department of Biosciences, Integral University, Lucknow 226026, India
| | - Irfan A Ansari
- Clinical Biochemistry & Natural Product Research Lab., Department of Biosciences, Integral University, Lucknow 226026, India
| | - Imran Khan
- Clinical Biochemistry & Natural Product Research Lab., Department of Biosciences, Integral University, Lucknow 226026, India
| | - Johar Iqbal
- Department of Biochemistry, Faculty of Medicine, Jazan University, Jazan, Kingdom of Saudi Arabia
| | - M Salman Khan
- Clinical Biochemistry & Natural Product Research Lab., Department of Biosciences, Integral University, Lucknow 226026, India.
| |
Collapse
|
34
|
Kitamura K, Okada Y, Okada K, Kawaguchi Y, Nagaoka S. Epigallocatechin gallate induces an up-regulation of LDL receptor accompanied by a reduction of PCSK9 via the annexin A2-independent pathway in HepG2 cells. Mol Nutr Food Res 2017; 61. [PMID: 28181408 DOI: 10.1002/mnfr.201600836] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 12/23/2016] [Accepted: 01/25/2017] [Indexed: 11/11/2022]
Abstract
SCOPE In animal studies, epigallocatechin gallate (EGCG), the dominant catechin in green tea, has been shown to improve cholesterol metabolism. However, the molecular mechanisms of EGCG underlying these functions have not been fully understood. In this study, we aimed to clarify the molecular mechanisms of the effect of EGCG on cholesterol metabolism mainly in HepG2 cells. METHODS AND RESULTS We found that EGCG induced a reduction of the extracellular proprotein convertase subtilisin/kexin 9 (PCSK9) level accompanied by an up-regulation of the LDL receptor (LDLR) in HepG2 cells. The EGCG-induced up-regulation of LDLR occurred via the extracellular signal-regulated kinase (ERK) signaling pathway. Moreover, we showed that EGCG induced a significant early reduction of the extracellular PCSK9 protein level. However, there were no significant changes in the PCSK9 mRNA and the intracellular PCSK9 protein levels induced by EGCG. Annexin A2 knockdown affected the basal LDLR expression and did not affect the EGCG-induced reduction of the extracellular PCSK9 protein level or the up-regulation of LDLR. CONCLUSION Annexin A2 possesses an essential function for the basal LDLR expression in HepG2 cells. But, EGCG induces the suppression of PCSK9 accompanied by an up-regulation of LDLR in an annexin A2-independent manner. EGCG attenuates the statin-induced an increase in PCSK9 level.
Collapse
Affiliation(s)
- Kohei Kitamura
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, Japan
| | - Yudai Okada
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, Japan
| | - Kenji Okada
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, Japan
| | - Yuya Kawaguchi
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, Japan
| | - Satoshi Nagaoka
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu, Japan
| |
Collapse
|
35
|
Pohlkamp T, Wasser CR, Herz J. Functional Roles of the Interaction of APP and Lipoprotein Receptors. Front Mol Neurosci 2017; 10:54. [PMID: 28298885 PMCID: PMC5331069 DOI: 10.3389/fnmol.2017.00054] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 02/16/2017] [Indexed: 11/24/2022] Open
Abstract
The biological fates of the key initiator of Alzheimer’s disease (AD), the amyloid precursor protein (APP), and a family of lipoprotein receptors, the low-density lipoprotein (LDL) receptor-related proteins (LRPs) and their molecular roles in the neurodegenerative disease process are inseparably interwoven. Not only does APP bind tightly to the extracellular domains (ECDs) of several members of the LRP group, their intracellular portions are also connected through scaffolds like the one established by FE65 proteins and through interactions with adaptor proteins such as X11/Mint and Dab1. Moreover, the ECDs of APP and LRPs share common ligands, most notably Reelin, a regulator of neuronal migration during embryonic development and modulator of synaptic transmission in the adult brain, and Agrin, another signaling protein which is essential for the formation and maintenance of the neuromuscular junction (NMJ) and which likely also has critical, though at this time less well defined, roles for the regulation of central synapses. Furthermore, the major independent risk factors for AD, Apolipoprotein (Apo) E and ApoJ/Clusterin, are lipoprotein ligands for LRPs. Receptors and ligands mutually influence their intracellular trafficking and thereby the functions and abilities of neurons and the blood-brain-barrier to turn over and remove the pathological product of APP, the amyloid-β peptide. This article will review and summarize the molecular mechanisms that are shared by APP and LRPs and discuss their relative contributions to AD.
Collapse
Affiliation(s)
- Theresa Pohlkamp
- Department of Molecular Genetics, UT Southwestern Medical CenterDallas, TX, USA; Center for Translational Neurodegeneration Research, UT Southwestern Medical CenterDallas, TX, USA
| | - Catherine R Wasser
- Department of Molecular Genetics, UT Southwestern Medical CenterDallas, TX, USA; Center for Translational Neurodegeneration Research, UT Southwestern Medical CenterDallas, TX, USA
| | - Joachim Herz
- Department of Molecular Genetics, UT Southwestern Medical CenterDallas, TX, USA; Center for Translational Neurodegeneration Research, UT Southwestern Medical CenterDallas, TX, USA; Department of Neuroscience, UT Southwestern Medical CenterDallas, TX, USA; Department of Neurology and Neurotherapeutics, UT Southwestern Medical CenterDallas, TX, USA
| |
Collapse
|
36
|
Susan-Resiga D, Girard E, Kiss RS, Essalmani R, Hamelin J, Asselin MC, Awan Z, Butkinaree C, Fleury A, Soldera A, Dory YL, Baass A, Seidah NG. The Proprotein Convertase Subtilisin/Kexin Type 9-resistant R410S Low Density Lipoprotein Receptor Mutation: A NOVEL MECHANISM CAUSING FAMILIAL HYPERCHOLESTEROLEMIA. J Biol Chem 2016; 292:1573-1590. [PMID: 27998977 DOI: 10.1074/jbc.m116.769430] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 12/20/2016] [Indexed: 12/22/2022] Open
Abstract
Familial hypercholesterolemia (FH) is characterized by severely elevated low density lipoprotein (LDL) cholesterol. Herein, we identified an FH patient presenting novel compound heterozygote mutations R410S and G592E of the LDL receptor (LDLR). The patient responded modestly to maximum rosuvastatin plus ezetimibe therapy, even in combination with a PCSK9 monoclonal antibody injection. Using cell biology and molecular dynamics simulations, we aimed to define the underlying mechanism(s) by which these LDLR mutations affect LDL metabolism and lead to hypercholesterolemia. Our data showed that the LDLR-G592E is a class 2b mutant, because it mostly failed to exit the endoplasmic reticulum and was degraded. Even though LDLR-R410S and LDLR-WT were similar in levels of cell surface and total receptor and bound equally well to LDL or extracellular PCSK9, the LDLR-R410S was resistant to exogenous PCSK9-mediated degradation in endosomes/lysosomes and showed reduced LDL internalization and degradation relative to LDLR-WT. Evidence is provided for a tighter association of LDL with LDLR-R410S at acidic pH, a reduced LDL delivery to late endosomes/lysosomes, and an increased release in the medium of the bound/internalized LDL, as compared with LDLR-WT. These data suggested that LDLR-R410S recycles loaded with its LDL-cargo. Our findings demonstrate that LDLR-R410S represents an LDLR loss-of-function through a novel class 8 FH-causing mechanism, thereby rationalizing the observed phenotype.
Collapse
Affiliation(s)
- Delia Susan-Resiga
- From the Laboratory of Biochemical Neuroendocrinology, Montreal, Quebec H2W 1R7, Canada
| | - Emmanuelle Girard
- From the Laboratory of Biochemical Neuroendocrinology, Montreal, Quebec H2W 1R7, Canada
| | - Robert Scott Kiss
- the Department of Medicine, McGill University, Montreal, Quebec H3G 2M1, Canada
| | - Rachid Essalmani
- From the Laboratory of Biochemical Neuroendocrinology, Montreal, Quebec H2W 1R7, Canada
| | - Josée Hamelin
- From the Laboratory of Biochemical Neuroendocrinology, Montreal, Quebec H2W 1R7, Canada
| | - Marie-Claude Asselin
- From the Laboratory of Biochemical Neuroendocrinology, Montreal, Quebec H2W 1R7, Canada
| | - Zuhier Awan
- From the Laboratory of Biochemical Neuroendocrinology, Montreal, Quebec H2W 1R7, Canada
| | - Chutikarn Butkinaree
- From the Laboratory of Biochemical Neuroendocrinology, Montreal, Quebec H2W 1R7, Canada
| | - Alexandre Fleury
- the Laboratory of Supramolecular Chemistry, Department of Chemistry, University of Sherbrooke, Sherbrooke, Quebec J1K 2R1, Canada
| | - Armand Soldera
- the Laboratory of Supramolecular Chemistry, Department of Chemistry, University of Sherbrooke, Sherbrooke, Quebec J1K 2R1, Canada
| | - Yves L Dory
- the Laboratory of Supramolecular Chemistry, Department of Chemistry, University of Sherbrooke, Sherbrooke, Quebec J1K 2R1, Canada
| | - Alexis Baass
- Nutrition, Metabolism, and Atherosclerosis Clinic, Institut de Recherches Cliniques de Montréal, affiliated with University of Montreal, Montreal, Quebec H2W 1R7, Canada
| | - Nabil G Seidah
- From the Laboratory of Biochemical Neuroendocrinology, Montreal, Quebec H2W 1R7, Canada.
| |
Collapse
|
37
|
Chen HC, Chen PY, Wu MJ, Tai MH, Yen JH. Tanshinone IIA Modulates Low Density Lipoprotein Uptake via Down-Regulation of PCSK9 Gene Expression in HepG2 Cells. PLoS One 2016; 11:e0162414. [PMID: 27617748 PMCID: PMC5019481 DOI: 10.1371/journal.pone.0162414] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 08/22/2016] [Indexed: 01/12/2023] Open
Abstract
Tanshinone IIA, one of the most pharmacologically bioactive phytochemicals isolated from Salvia miltiorrhiza Bunge, possesses several biological activities such as anti-inflammation, anti-cancer, neuroprotection and hypolipidemic activities. In this study, we aim to investigate the hypocholesterolemic effect of tanshinone IIA in hepatic cells. We demonstrated that tanshinone IIA significantly increased the amount of low-density lipoprotein receptor (LDLR) and LDL uptake activity in HepG2 cells at the post-transcriptional regulation. We further demonstrated that tanshinone IIA inhibited the expression of proprotein convertase subtilisin/kexin type 9 (PCSK9) mRNA and mature protein, which may lead to an increase the cell-surface LDLR in hepatic cells. We further identified a regulatory DNA element involved in the tanshinone IIA-mediated PCSK9 down-regulation, which is located between the -411 and -336 positions of the PCSK9 promoter. Moreover, we found that tanshinone IIA markedly increased the nuclear forkhead box O3a (FoxO3a) level, enhanced FoxO3a/PCSK9 promoter complexes formation and decreased the PCSK9 promoter binding capacity of hepatocyte nuclear factor 1α (HNF-1α), resulting in suppression of PCSK9 gene expression. Finally, we found that the statin-induced PCSK9 overexpression was attenuated and the LDLR activity was elevated in a synergic manner by combination of tanshinone IIA treatment in HepG2 cells. Overall, our results reveal that the tanshinone IIA modulates LDLR level and activity via down-regulation of PCSK9 expression in hepatic cells. Our current findings provide a molecular basis of tanshinone IIA to develop PCSK9 inhibitors for cholesterol management.
Collapse
Affiliation(s)
- Hung-Chen Chen
- Department of Molecular Biology and Human Genetics, Tzu Chi University, Hualien, Taiwan
| | - Pei-Yi Chen
- Center of Medical Genetics, Buddhist Tzu Chi General Hospital, Hualien, Taiwan
| | - Ming-Jiuan Wu
- Department of Biotechnology, Chia-Nan University of Pharmacy and Science, Tainan, Taiwan
| | - Mi-Hsueh Tai
- Department of Molecular Biology and Human Genetics, Tzu Chi University, Hualien, Taiwan
| | - Jui-Hung Yen
- Department of Molecular Biology and Human Genetics, Tzu Chi University, Hualien, Taiwan
- * E-mail:
| |
Collapse
|
38
|
Structural basis of transcobalamin recognition by human CD320 receptor. Nat Commun 2016; 7:12100. [PMID: 27411955 PMCID: PMC4947154 DOI: 10.1038/ncomms12100] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 05/27/2016] [Indexed: 12/20/2022] Open
Abstract
Cellular uptake of vitamin B12 (cobalamin) requires capture of transcobalamin (TC) from the plasma by CD320, a ubiquitous cell surface receptor of the LDLR family. Here we present the crystal structure of human holo-TC in complex with the extracellular domain of CD320, visualizing the structural basis of the TC-CD320 interaction. The observed interaction chemistry can rationalize the high affinity of CD320 for TC and lack of haptocorrin binding. The in vitro affinity and complex stability of TC-CD320 were quantitated using a solid-phase binding assay and thermostability analysis. Stable complexes with TC were also observed for the disease-causing CD320ΔE88 mutant and for the isolated LDLR-A2 domain. We also determined the structure of the TC-CD320ΔE88 complex, which revealed only minor changes compared with the wild-type complex. Finally, we demonstrate significantly reduced in vitro affinity of TC for CD320 at low pH, recapitulating the proposed ligand release during the endocytic pathway. Cellular uptake of vitamin B12 (cobalamin) requires the binding of holo-transcobalamin (TC) from plasma by CD320. Here, the authors report the structure of a complex between CD320 and TC loaded with cyanocobalamin, alongside additional functional analysis.
Collapse
|
39
|
Bochkov YA, Gern JE. Rhinoviruses and Their Receptors: Implications for Allergic Disease. Curr Allergy Asthma Rep 2016; 16:30. [PMID: 26960297 DOI: 10.1007/s11882-016-0608-7] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Human rhinoviruses (RVs) are picornaviruses that can cause a variety of illnesses including the common cold, lower respiratory tract illnesses such as bronchitis and pneumonia, and exacerbations of asthma. RVs are classified into three species, RV-A, B, and C, which include over 160 types. They utilize three major types of cellular membrane glycoproteins to gain entry into the host cell: intercellular adhesion molecule 1 (ICAM-1) (the majority of RV-A and all RV-B), low-density lipoprotein receptor (LDLR) family members (12 RV-A types), and cadherin-related family member 3 (CDHR3) (RV-C). CDHR3 is a member of cadherin superfamily of transmembrane proteins with yet unknown biological function, and there is relatively little information available about the mechanisms of RV-C interaction with CDHR3. A coding single nucleotide polymorphism (rs6967330) in CDHR3 could promote RV-C infections and illnesses in infancy, which could in turn adversely affect the developing lung to increase the risk of asthma. Further studies are needed to determine how RV infections contribute to pathogenesis of asthma and to develop the optimal treatment approach to control asthma exacerbations.
Collapse
Affiliation(s)
- Yury A Bochkov
- Department of Pediatrics, School of Medicine and Public Health, University of Wisconsin-Madison, 600 Highland Ave, Madison, WI, 53792, USA.
| | - James E Gern
- Department of Pediatrics, School of Medicine and Public Health, University of Wisconsin-Madison, 600 Highland Ave, Madison, WI, 53792, USA.,Department of Medicine, School of Medicine and Public Health, University of Wisconsin-Madison, 600 Highland Ave, Madison, WI, 53792, USA
| |
Collapse
|
40
|
Very mild features of dysequilibrium syndrome associated with a novel VLDLR missense mutation. Neurogenetics 2016; 17:191-5. [PMID: 27251579 DOI: 10.1007/s10048-016-0488-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 05/29/2016] [Indexed: 10/21/2022]
Abstract
Dysequilibrium syndrome (DES) is a non-progressive congenital ataxia characterized by severe intellectual deficit, truncal ataxia and markedly delayed, quadrupedal or absent ambulation. Recessive loss-of-function mutations in the very low density lipoprotein receptor (VLDLR) gene represent the most common cause of DES. Only two families have been reported harbouring homozygous missense mutations, both with a similarly severe phenotype. We report an Italian girl with very mild DES caused by the novel homozygous VLDLR missense mutation p.(C419Y). This unusually benign phenotype possibly relates to a less disruptive effect of the mutation, falling within a domain (EGF-B) not predicted as crucial for the protein function.
Collapse
|
41
|
Blaas D. Viral entry pathways: the example of common cold viruses. Wien Med Wochenschr 2016; 166:211-26. [PMID: 27174165 PMCID: PMC4871925 DOI: 10.1007/s10354-016-0461-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2016] [Accepted: 04/12/2016] [Indexed: 02/02/2023]
Abstract
For infection, viruses deliver their genomes into the host cell. These nucleic acids are usually tightly packed within the viral capsid, which, in turn, is often further enveloped within a lipid membrane. Both protect them against the hostile environment. Proteins and/or lipids on the viral particle promote attachment to the cell surface and internalization. They are likewise often involved in release of the genome inside the cell for its use as a blueprint for production of new viruses. In the following, I shall cursorily discuss the early more general steps of viral infection that include receptor recognition, uptake into the cell, and uncoating of the viral genome. The later sections will concentrate on human rhinoviruses, the main cause of the common cold, with respect to the above processes. Much of what is known on the underlying mechanisms has been worked out by Renate Fuchs at the Medical University of Vienna.
Collapse
Affiliation(s)
- Dieter Blaas
- Max F. Perutz Laboratories, Department of Medical Biochemistry, Medical University of Vienna, Vienna Biocenter, Dr. Bohr Gasse 9/3, 1030, Vienna, Austria.
| |
Collapse
|
42
|
Pillay S, Meyer NL, Puschnik AS, Davulcu O, Diep J, Ishikawa Y, Jae LT, Wosen JE, Nagamine CM, Chapman MS, Carette JE. An essential receptor for adeno-associated virus infection. Nature 2016; 530:108-12. [PMID: 26814968 PMCID: PMC4962915 DOI: 10.1038/nature16465] [Citation(s) in RCA: 345] [Impact Index Per Article: 38.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 11/18/2015] [Indexed: 01/20/2023]
Affiliation(s)
- S Pillay
- Department of Microbiology and Immunology, Stanford University School of Medicine, 299 Campus Drive, Stanford, California 94305, USA
| | - N L Meyer
- Department of Biochemistry and Molecular Biology, School of Medicine, Oregon Health &Science University, 3181 Sam Jackson Park Road, Portland, Oregon 97239-3098, USA
| | - A S Puschnik
- Department of Microbiology and Immunology, Stanford University School of Medicine, 299 Campus Drive, Stanford, California 94305, USA
| | - O Davulcu
- Department of Biochemistry and Molecular Biology, School of Medicine, Oregon Health &Science University, 3181 Sam Jackson Park Road, Portland, Oregon 97239-3098, USA
| | - J Diep
- Department of Microbiology and Immunology, Stanford University School of Medicine, 299 Campus Drive, Stanford, California 94305, USA
| | - Y Ishikawa
- Department of Biochemistry and Molecular Biology, School of Medicine, Oregon Health &Science University, 3181 Sam Jackson Park Road, Portland, Oregon 97239-3098, USA.,Shriners Hospital for Children, 3101 Sam Jackson Park Road, Portland, Oregon 97239, USA
| | - L T Jae
- Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, Netherlands
| | - J E Wosen
- Department of Microbiology and Immunology, Stanford University School of Medicine, 299 Campus Drive, Stanford, California 94305, USA
| | - C M Nagamine
- Department of Comparative Medicine, Stanford University School of Medicine, 287 Campus Drive, Stanford, California 94305, USA
| | - M S Chapman
- Department of Biochemistry and Molecular Biology, School of Medicine, Oregon Health &Science University, 3181 Sam Jackson Park Road, Portland, Oregon 97239-3098, USA
| | - J E Carette
- Department of Microbiology and Immunology, Stanford University School of Medicine, 299 Campus Drive, Stanford, California 94305, USA
| |
Collapse
|
43
|
Angarica VE, Orozco M, Sancho J. Exploring the complete mutational space of the LDL receptor LA5 domain using molecular dynamics: linking SNPs with disease phenotypes in familial hypercholesterolemia. Hum Mol Genet 2016; 25:1233-46. [PMID: 26755827 PMCID: PMC4764198 DOI: 10.1093/hmg/ddw004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 01/05/2016] [Indexed: 11/18/2022] Open
Abstract
Familial hypercholesterolemia (FH), a genetic disorder with a prevalence of 0.2%, represents a high-risk factor to develop cardiovascular and cerebrovascular diseases. The majority and most severe FH cases are associated to mutations in the receptor for low-density lipoproteins receptor (LDL-r), but the molecular basis explaining the connection between mutation and phenotype is often unknown, which hinders early diagnosis and treatment of the disease. We have used atomistic simulations to explore the complete SNP mutational space (227 mutants) of the LA5 repeat, the key domain for interacting with LDL that is coded in the exon concentrating the highest number of mutations. Four clusters of mutants of different stability have been identified. The majority of the 50 FH known mutations (33) appear distributed in the unstable clusters, i.e. loss of conformational stability explains two-third of FH phenotypes. However, one-third of FH phenotypes (17 mutations) do not destabilize the LR5 repeat. Combining our simulations with available structural data from different laboratories, we have defined a consensus-binding site for the interaction of the LA5 repeat with LDL-r partner proteins and have found that most (16) of the 17 stable FH mutations occur at binding site residues. Thus, LA5-associated FH arises from mutations that cause either the loss of stability or a decrease in domain's-binding affinity. Based on this finding, we propose the likely phenotype of each possible SNP in the LA5 repeat and outline a procedure to make a full computational diagnosis for FH.
Collapse
Affiliation(s)
- Vladimir Espinosa Angarica
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain, Biocomputation and Complex Systems Physics Institute (BIFI), Joint Unit BIFI-IQFR (CSIC), Universidad de Zaragoza, Mariano Esquillor, Edificio I + D, 50018 Zaragoza, Spain
| | - Modesto Orozco
- Institut de Recerca Biomèdica (IRB Barcelona), Baldiri Reixac 10-12, 08028 Barcelona, Spain, Departament de Bioquímica i Biologia Molecular, Universitat de Barcelona, Diagonal 643, 08028 Barcelona, Spain, Joint BSC-CRG-IRB Program in Computational Biology, Baldiri Reixac 10-12, 08028 Barcelona, Spain, and
| | - Javier Sancho
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain, Biocomputation and Complex Systems Physics Institute (BIFI), Joint Unit BIFI-IQFR (CSIC), Universidad de Zaragoza, Mariano Esquillor, Edificio I + D, 50018 Zaragoza, Spain, Aragon Institute for Health Research (IIS Aragón), Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain
| |
Collapse
|
44
|
Martínez-Oliván J, Arias-Moreno X, Hurtado-Guerrero R, Carrodeguas JA, Miguel-Romero L, Marina A, Bruscolini P, Sancho J. The closed conformation of the LDL receptor is destabilized by the low Ca(++) concentration but favored by the high Mg(++) concentration in the endosome. FEBS Lett 2015; 589:3534-40. [PMID: 26526611 DOI: 10.1016/j.febslet.2015.10.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 10/06/2015] [Accepted: 10/14/2015] [Indexed: 10/22/2022]
Abstract
The LDL receptor (LDLR) internalizes LDL and VLDL particles. In the endosomes, it adopts a closed conformation important for recycling, by interaction of two modules of the ligand binding domain (LR4-5) and a β-propeller motif. Here, we investigate by SPR the interactions between those two modules and the β-propeller. Our results indicate that the two modules cooperate to bind the β-propeller. The binding is favored by low pH and by high [Ca(++)]. Our data show that Mg(++), at high concentration in the endosome, favors the formation of the closed conformation by replacing the structuring effect of Ca(++) in LR5. We propose a sequential model of LDL release where formation of the close conformation follows LDL release.
Collapse
Affiliation(s)
- Juan Martínez-Oliván
- Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Unit BIFI-IQFR (CSIC), Universidad de Zaragoza, Zaragoza, Spain; Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, Zaragoza, Spain; Aragon Health Research Institute (IIS Aragón), Universidad de Zaragoza, Zaragoza, Spain
| | - Xabier Arias-Moreno
- Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Unit BIFI-IQFR (CSIC), Universidad de Zaragoza, Zaragoza, Spain; Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, Zaragoza, Spain
| | - Ramón Hurtado-Guerrero
- Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Unit BIFI-IQFR (CSIC), Universidad de Zaragoza, Zaragoza, Spain; Aragon Health Research Institute (IIS Aragón), Universidad de Zaragoza, Zaragoza, Spain; Fundación ARAID, Diputación General de Aragón, Spain
| | - José Alberto Carrodeguas
- Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Unit BIFI-IQFR (CSIC), Universidad de Zaragoza, Zaragoza, Spain; Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, Zaragoza, Spain; Aragon Health Research Institute (IIS Aragón), Universidad de Zaragoza, Zaragoza, Spain
| | - Laura Miguel-Romero
- Instituto de Biomedicina de Valencia, Consejo Superior de Investigaciones Científicas (IBV-CSIC), Spain
| | - Alberto Marina
- Instituto de Biomedicina de Valencia, Consejo Superior de Investigaciones Científicas (IBV-CSIC), Spain
| | - Pierpaolo Bruscolini
- Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Unit BIFI-IQFR (CSIC), Universidad de Zaragoza, Zaragoza, Spain
| | - Javier Sancho
- Biocomputation and Complex Systems Physics Institute (BIFI)-Joint Unit BIFI-IQFR (CSIC), Universidad de Zaragoza, Zaragoza, Spain; Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, Zaragoza, Spain; Aragon Health Research Institute (IIS Aragón), Universidad de Zaragoza, Zaragoza, Spain.
| |
Collapse
|
45
|
Van der Horst DJ, Rodenburg KW. Lipoprotein assembly and function in an evolutionary perspective. Biomol Concepts 2015; 1:165-83. [PMID: 25961995 DOI: 10.1515/bmc.2010.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Circulatory fat transport in animals relies on members of the large lipid transfer protein (LLTP) superfamily, including mammalian apolipoprotein B (apoB) and insect apolipophorin II/I (apoLp-II/I). ApoB and apoLp-II/I, constituting the structural (non-exchangeable) basis for the assembly of various lipoproteins, acquire lipids through microsomal triglyceride-transfer protein, another LLTP family member, and bind them by means of amphipathic α-helical and β-sheet structural motifs. Comparative research reveals that LLTPs evolved from the earliest animals and highlights the structural adaptations in these lipid-binding proteins. Thus, in contrast to apoB, apoLp-II/I is cleaved post-translationally by a furin, resulting in the appearance of two non-exchangeable apolipoproteins in the single circulatory lipoprotein in insects, high-density lipophorin (HDLp). The remarkable structural similarities between mammalian and insect lipoproteins notwithstanding important functional differences relate to the mechanism of lipid delivery. Whereas in mammals, partial delipidation of apoB-containing lipoproteins eventually results in endocytic uptake of their remnants, mediated by members of the low-density lipoprotein receptor (LDLR) family, and degradation in lysosomes, insect HDLp functions as a reusable lipid shuttle capable of alternate unloading and reloading of lipid. Also, during muscular efforts (flight activity), an HDLp-based lipoprotein shuttle provides for the transport of lipid for energy generation. Although a lipophorin receptor - a homolog of LDLR - was identified that mediates endocytic uptake of HDLp during specific developmental periods, the endocytosed lipoprotein appears to be recycled in a transferrin-like manner. These data highlight that the functional adaptations in the lipoprotein lipid carriers in mammals and insects also emerge with regard to the functioning of their cognate receptors.
Collapse
|
46
|
Kitago Y, Nagae M, Nakata Z, Yagi-Utsumi M, Takagi-Niidome S, Mihara E, Nogi T, Kato K, Takagi J. Structural basis for amyloidogenic peptide recognition by sorLA. Nat Struct Mol Biol 2015; 22:199-206. [PMID: 25643321 DOI: 10.1038/nsmb.2954] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2014] [Accepted: 12/15/2014] [Indexed: 11/09/2022]
Abstract
SorLA is a neuronal sorting receptor considered to be a major risk factor for Alzheimer's disease. We have recently reported that it directs lysosomal targeting of nascent neurotoxic amyloid-β (Aβ) peptides by directly binding Aβ. Here, we determined the crystal structure of the human sorLA domain responsible for Aβ capture, Vps10p, in an unbound state and in complex with two ligands. Vps10p assumes a ten-bladed β-propeller fold with a large tunnel at the center. An internal ligand derived from the sorLA propeptide bound inside the tunnel to extend the β-sheet of one of the propeller blades. The structure of the sorLA Vps10p-Aβ complex revealed that the same site is used. Peptides are recognized by sorLA Vps10p in redundant modes without strict dependence on a particular amino acid sequence, thus suggesting a broad specificity toward peptides with a propensity for β-sheet formation.
Collapse
Affiliation(s)
- Yu Kitago
- Institute for Protein Research, Osaka University, Suita, Japan
| | - Masamichi Nagae
- Institute for Protein Research, Osaka University, Suita, Japan
| | | | - Maho Yagi-Utsumi
- 1] Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, Okazaki, Japan. [2] Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
| | | | - Emiko Mihara
- Institute for Protein Research, Osaka University, Suita, Japan
| | - Terukazu Nogi
- Graduate School of Medical Life Science, Yokohama City University, Yokohama, Japan
| | - Koichi Kato
- 1] Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, Okazaki, Japan. [2] Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
| | - Junichi Takagi
- Institute for Protein Research, Osaka University, Suita, Japan
| |
Collapse
|
47
|
Mehmedbasic A, Christensen SK, Nilsson J, Rüetschi U, Gustafsen C, Poulsen ASA, Rasmussen RW, Fjorback AN, Larson G, Andersen OM. SorLA complement-type repeat domains protect the amyloid precursor protein against processing. J Biol Chem 2014; 290:3359-76. [PMID: 25525276 DOI: 10.1074/jbc.m114.619940] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
SorLA is a neuronal sorting receptor that is genetically associated with Alzheimer disease. SorLA interacts directly with the amyloid precursor protein (APP) and affects the processing of the precursor, leading to a decreased generation of the amyloid-β peptide. The SorLA complement-type repeat (CR) domains associate in vitro with APP, but the precise molecular determinants of SorLA·APP complex formation and the mechanisms responsible for the effect of binding on APP processing have not yet been elucidated. Here, we have generated protein expression constructs for SorLA devoid of the 11 CR-domains and for two SorLA mutants harboring substitutions of the fingerprint residues in the central CR-domains. We generated SH-SY5Y cell lines that stably express these SorLA variants to study the binding and processing of APP using co-immunoprecipitation and Western blotting/ELISAs, respectively. We found that the SorLA CR-cluster is essential for interaction with APP and that deletion of the CR-cluster abolishes the protection against APP processing. Mutation of identified fingerprint residues in the SorLA CR-domains leads to changes in the O-linked glycosylation of APP when expressed in SH-SY5Y cells. Our results provide novel information on the mechanisms behind the influence of SorLA activity on APP metabolism by controlling post-translational glycosylation in the Golgi, suggesting new strategies against amyloidogenesis in Alzheimer disease.
Collapse
Affiliation(s)
- Arnela Mehmedbasic
- From the Lundbeck Foundation Research Center MIND, Danish Research Institute of Translational Neuroscience Nordic-EMBL Partnership (DANDRITE), Department of Biomedicine, Aarhus University, Ole Worms Allé 3, DK-8000 AarhusC, Denmark and
| | - Sofie K Christensen
- From the Lundbeck Foundation Research Center MIND, Danish Research Institute of Translational Neuroscience Nordic-EMBL Partnership (DANDRITE), Department of Biomedicine, Aarhus University, Ole Worms Allé 3, DK-8000 AarhusC, Denmark and
| | - Jonas Nilsson
- the Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, University of Gothenburg, SE-413 45 Gothenburg, Sweden
| | - Ulla Rüetschi
- the Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, University of Gothenburg, SE-413 45 Gothenburg, Sweden
| | - Camilla Gustafsen
- From the Lundbeck Foundation Research Center MIND, Danish Research Institute of Translational Neuroscience Nordic-EMBL Partnership (DANDRITE), Department of Biomedicine, Aarhus University, Ole Worms Allé 3, DK-8000 AarhusC, Denmark and
| | - Annemarie Svane Aavild Poulsen
- From the Lundbeck Foundation Research Center MIND, Danish Research Institute of Translational Neuroscience Nordic-EMBL Partnership (DANDRITE), Department of Biomedicine, Aarhus University, Ole Worms Allé 3, DK-8000 AarhusC, Denmark and
| | - Rikke W Rasmussen
- From the Lundbeck Foundation Research Center MIND, Danish Research Institute of Translational Neuroscience Nordic-EMBL Partnership (DANDRITE), Department of Biomedicine, Aarhus University, Ole Worms Allé 3, DK-8000 AarhusC, Denmark and
| | - Anja N Fjorback
- From the Lundbeck Foundation Research Center MIND, Danish Research Institute of Translational Neuroscience Nordic-EMBL Partnership (DANDRITE), Department of Biomedicine, Aarhus University, Ole Worms Allé 3, DK-8000 AarhusC, Denmark and
| | - Göran Larson
- the Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, University of Gothenburg, SE-413 45 Gothenburg, Sweden
| | - Olav M Andersen
- From the Lundbeck Foundation Research Center MIND, Danish Research Institute of Translational Neuroscience Nordic-EMBL Partnership (DANDRITE), Department of Biomedicine, Aarhus University, Ole Worms Allé 3, DK-8000 AarhusC, Denmark and
| |
Collapse
|
48
|
Tai MH, Chen PK, Chen PY, Wu MJ, Ho CT, Yen JH. Curcumin enhances cell-surface LDLR level and promotes LDL uptake through downregulation of PCSK9 gene expression in HepG2 cells. Mol Nutr Food Res 2014; 58:2133-45. [DOI: 10.1002/mnfr.201400366] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 07/30/2014] [Accepted: 08/19/2014] [Indexed: 01/06/2023]
Affiliation(s)
- Mi-Hsueh Tai
- Department of Molecular Biology and Human Genetics; Tzu Chi University; Hualien Taiwan
| | - Po-Kong Chen
- Department of Molecular Biology and Human Genetics; Tzu Chi University; Hualien Taiwan
| | - Pei-Yi Chen
- Center of Medical Genetics; Buddhist Tzu Chi General Hospital; Hualien Taiwan
| | - Ming-Jiuan Wu
- Department of Biotechnology; Chia Nan University of Pharmacy and Science; Tainan Taiwan
| | - Chi-Tang Ho
- Department of Food Science; Rutgers University; NJ USA
| | - Jui-Hung Yen
- Department of Molecular Biology and Human Genetics; Tzu Chi University; Hualien Taiwan
| |
Collapse
|
49
|
Martínez-Oliván J, Rozado-Aguirre Z, Arias-Moreno X, Angarica VE, Velázquez-Campoy A, Sancho J. Low-density lipoprotein receptor is a calcium/magnesium sensor - role of LR4 and LR5 ion interaction kinetics in low-density lipoprotein release in the endosome. FEBS J 2014; 281:2638-58. [PMID: 24720672 DOI: 10.1111/febs.12811] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 03/25/2014] [Accepted: 04/08/2014] [Indexed: 11/28/2022]
Abstract
The low-density lipoprotein receptor (LDLR) captures circulating lipoproteins and delivers them in the endosome for degradation. Its function is essential for cholesterol homeostasis, and mutations in the LDLR are the major cause of familiar hypercholesterolemia. The release of LDL is usually attributed to endosome acidification. As the pH drops, the affinity of the LDLR/LDL complex is reduced, whereas the strength of a self-complex formed between two domains of the receptor (i.e. the LDL binding domain and the β-propeller domain) increases. However, an alternative model states that, as a consequence of a drop in both pH and Ca(2+) concentration, the LDLR binding domain is destabilized in the endosome, which weakens the LDLR/LDL complex, thus liberating the LDL particles. In the present study, we test a key underlying assumption of the second model, namely that the lipoprotein binding repeats of the receptor (specifically repeats 4 and 5, LR4 and LR5) rapidly sense endosomal changes in Ca(2+) concentration. Our kinetic and thermodynamic analysis of Ca(2+) and Mg(2+) binding to LR4 and LR5, as well as to the tandem of the two (LR4-5), shows that both repeats spontaneously release Ca(2+) in a time scale much shorter than endosomal delivery of LDL, thus acting as Ca(2+) sensors that become unfolded under endosomal conditions. Our analysis additionally explains the lower Ca(2+) affinity of repeat LR4, compared to LR5, as arising from a very slow Ca(2+) binding reaction in the former, most likely related to the lower conformational stability of apolipoprotein LR4, compared to apolipoprotein LR5, as determined from thermal unfolding experiments and molecular dynamics simulations.
Collapse
Affiliation(s)
- Juan Martínez-Oliván
- Biocomputation and Complex Systems Physics Institute (BIFI) - Joint Unit BIFI-IQFR (CSIC), Universidad de Zaragoza, Spain; Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, Spain
| | | | | | | | | | | |
Collapse
|
50
|
Andersen OM, Dagil R, Kragelund BB. New horizons for lipoprotein receptors: communication by β-propellers. J Lipid Res 2013; 54:2763-74. [PMID: 23881912 DOI: 10.1194/jlr.m039545] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The lipoprotein receptor (LR) family constitutes a large group of structurally closely related receptors with broad ligand-binding specificity. Traditionally, ligand binding to LRs has been anticipated to involve merely the complement type repeat (CR)-domains omnipresent in the family. Recently, this dogma has transformed with the observation that β-propellers of some LRs actively engage in complex formation too. Based on an in-depth decomposition of current structures and sequences, we suggest that exploitation of the β-propellers as binding targets depends on receptor subgroups. In particular, we highlight the shutter mechanism of β-propellers as a general recognition motif for NxI-containing ligands, and we present indications that the generalized β-propeller-induced ligand release mechanism is not applicable for the larger LRs. For the giant LR members, we present evidence that their β-propellers may also actively engage in ligand binding. We therefore advocate for an increased focus on solving the structure-function relationship of this group of important biological receptors.
Collapse
Affiliation(s)
- Olav M Andersen
- Department of Biomedicine, Aarhus University, DK-8000 Aarhus C, Denmark; and
| | | | | |
Collapse
|