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Wang L, Xie Z, Wu M, Chen Y, Wang X, Li X, Liu F. The role of taurine through endoplasmic reticulum in physiology and pathology. Biochem Pharmacol 2024; 226:116386. [PMID: 38909788 DOI: 10.1016/j.bcp.2024.116386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2024] [Revised: 06/17/2024] [Accepted: 06/20/2024] [Indexed: 06/25/2024]
Abstract
Taurine is a sulfur-containing amino acid found in many cell organelles that plays a wide range of biological roles, including bile salt production, osmoregulation, oxidative stress reduction, and neuromodulation. Taurine treatments have also been shown to ameliorate the onset and development of many diseases, including hypertension, fatty liver, neurodegenerative diseases and ischemia-reperfusion injury, by exerting antioxidant, anti-inflammatory, and antiapoptotic effects. The endoplasmic reticulum (ER) is a dynamic organelle involved in a wide range of cellular functions, including lipid metabolism, calcium storage and protein stabilization. Under stress, the disruption of the ER environment leads to the accumulation of misfolded proteins and a characteristic stress response called the unfolded protein response (UPR). The UPR protects cells from stress and helps to restore cellular homeostasis, but its activation promotes cell death under prolonged ER stress. Recent studies have shown that ER stress is closely related to the onset and development of many diseases. This article reviews the beneficial effects and related mechanisms of taurine by regulating the ER in different physiological and pathological states, with the aim of providing a reference for further research and clinical applications.
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Affiliation(s)
- Linfeng Wang
- Institute of Microbial Engineering, School of Life Sciences, Henan University, Kaifeng 475004, China; Engineering Research Center for Applied Microbiology of Henan Province, Kaifeng, 475004, China
| | - Zhenxing Xie
- School of Basic Medical Sciences, Henan University, Kaifeng 475004, China
| | - Mengxian Wu
- Institute of Microbial Engineering, School of Life Sciences, Henan University, Kaifeng 475004, China; Engineering Research Center for Applied Microbiology of Henan Province, Kaifeng, 475004, China
| | - Yunayuan Chen
- Institute of Microbial Engineering, School of Life Sciences, Henan University, Kaifeng 475004, China; Engineering Research Center for Applied Microbiology of Henan Province, Kaifeng, 475004, China
| | - Xin Wang
- Institute of Microbial Engineering, School of Life Sciences, Henan University, Kaifeng 475004, China; Engineering Research Center for Applied Microbiology of Henan Province, Kaifeng, 475004, China
| | - Xingke Li
- Institute of Microbial Engineering, School of Life Sciences, Henan University, Kaifeng 475004, China; Engineering Research Center for Applied Microbiology of Henan Province, Kaifeng, 475004, China.
| | - Fangli Liu
- College of Nursing and Health, Henan University, Kaifeng 475004, China.
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Jakobsen S, Nielsen CU. Exploring Amino Acid Transporters as Therapeutic Targets for Cancer: An Examination of Inhibitor Structures, Selectivity Issues, and Discovery Approaches. Pharmaceutics 2024; 16:197. [PMID: 38399253 PMCID: PMC10893028 DOI: 10.3390/pharmaceutics16020197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 01/18/2024] [Accepted: 01/28/2024] [Indexed: 02/25/2024] Open
Abstract
Amino acid transporters are abundant amongst the solute carrier family and have an important role in facilitating the transfer of amino acids across cell membranes. Because of their impact on cell nutrient distribution, they also appear to have an important role in the growth and development of cancer. Naturally, this has made amino acid transporters a novel target of interest for the development of new anticancer drugs. Many attempts have been made to develop inhibitors of amino acid transporters to slow down cancer cell growth, and some have even reached clinical trials. The purpose of this review is to help organize the available information on the efforts to discover amino acid transporter inhibitors by focusing on the amino acid transporters ASCT2 (SLC1A5), LAT1 (SLC7A5), xCT (SLC7A11), SNAT1 (SLC38A1), SNAT2 (SLC38A2), and PAT1 (SLC36A1). We discuss the function of the transporters, their implication in cancer, their known inhibitors, issues regarding selective inhibitors, and the efforts and strategies of discovering inhibitors. The goal is to encourage researchers to continue the search and development within the field of cancer treatment research targeting amino acid transporters.
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Affiliation(s)
- Sebastian Jakobsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark
| | - Carsten Uhd Nielsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark
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Khan MZ, Huang B, Kou X, Chen Y, Liang H, Ullah Q, Khan IM, Khan A, Chai W, Wang C. Enhancing bovine immune, antioxidant and anti-inflammatory responses with vitamins, rumen-protected amino acids, and trace minerals to prevent periparturient mastitis. Front Immunol 2024; 14:1290044. [PMID: 38259482 PMCID: PMC10800369 DOI: 10.3389/fimmu.2023.1290044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 12/05/2023] [Indexed: 01/24/2024] Open
Abstract
Mastitis, the inflammatory condition of mammary glands, has been closely associated with immune suppression and imbalances between antioxidants and free radicals in cattle. During the periparturient period, dairy cows experience negative energy balance (NEB) due to metabolic stress, leading to elevated oxidative stress and compromised immunity. The resulting abnormal regulation of reactive oxygen species (ROS) and reactive nitrogen species (RNS), along with increased non-esterified fatty acids (NEFA) and β-hydroxybutyric acid (BHBA) are the key factors associated with suppressed immunity thereby increases susceptibility of dairy cattle to infections, including mastitis. Metabolic diseases such as ketosis and hypocalcemia indirectly contribute to mastitis vulnerability, exacerbated by compromised immune function and exposure to physical injuries. Oxidative stress, arising from disrupted balance between ROS generation and antioxidant availability during pregnancy and calving, further contributes to mastitis susceptibility. Metabolic stress, marked by excessive lipid mobilization, exacerbates immune depression and oxidative stress. These factors collectively compromise animal health, productive efficiency, and udder health during periparturient phases. Numerous studies have investigated nutrition-based strategies to counter these challenges. Specifically, amino acids, trace minerals, and vitamins have emerged as crucial contributors to udder health. This review comprehensively examines their roles in promoting udder health during the periparturient phase. Trace minerals like copper, selenium, and calcium, as well as vitamins; have demonstrated significant impacts on immune regulation and antioxidant defense. Vitamin B12 and vitamin E have shown promise in improving metabolic function and reducing oxidative stress followed by enhanced immunity. Additionally, amino acids play a pivotal role in maintaining cellular oxidative balance through their involvement in vital biosynthesis pathways. In conclusion, addressing periparturient mastitis requires a holistic understanding of the interplay between metabolic stress, immune regulation, and oxidative balance. The supplementation of essential amino acids, trace minerals, and vitamins emerges as a promising avenue to enhance udder health and overall productivity during this critical phase. This comprehensive review underscores the potential of nutritional interventions in mitigating periparturient bovine mastitis and lays the foundation for future research in this domain.
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Affiliation(s)
- Muhammad Zahoor Khan
- Liaocheng Research Institute of Donkey High-efficiency Breeding and Ecological Feeding, Liaocheng University, Liaocheng, China
| | - Bingjian Huang
- Liaocheng Research Institute of Donkey High-efficiency Breeding and Ecological Feeding, Liaocheng University, Liaocheng, China
- College of Life Sciences, Liaocheng University, Liaocheng, China
| | - Xiyan Kou
- Liaocheng Research Institute of Donkey High-efficiency Breeding and Ecological Feeding, Liaocheng University, Liaocheng, China
| | - Yinghui Chen
- Liaocheng Research Institute of Donkey High-efficiency Breeding and Ecological Feeding, Liaocheng University, Liaocheng, China
| | - Huili Liang
- Liaocheng Research Institute of Donkey High-efficiency Breeding and Ecological Feeding, Liaocheng University, Liaocheng, China
| | - Qudrat Ullah
- Faculty of Veterinary and Animal Sciences, University of Agriculture, Dera Ismail Khan, Pakistan
| | | | - Adnan Khan
- Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Wenqiong Chai
- Liaocheng Research Institute of Donkey High-efficiency Breeding and Ecological Feeding, Liaocheng University, Liaocheng, China
| | - Changfa Wang
- Liaocheng Research Institute of Donkey High-efficiency Breeding and Ecological Feeding, Liaocheng University, Liaocheng, China
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Lintao RCV, Kammala AK, Vora N, Yaklic JL, Menon R. Fetal membranes exhibit similar nutrient transporter expression profiles to the placenta. Placenta 2023; 135:33-42. [PMID: 36913807 DOI: 10.1016/j.placenta.2023.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 03/03/2023] [Accepted: 03/06/2023] [Indexed: 03/09/2023]
Abstract
INTRODUCTION During pregnancy, the growth of the fetus is supported by the exchange of nutrients, waste, and other molecules between maternal and fetal circulations in the utero-placental unit. Nutrient transfer, in particular, is mediated by solute transporters such as solute carrier (SLC) and adenosine triphosphate-binding cassette (ABC) proteins. While nutrient transport has been extensively studied in the placenta, the role of human fetal membranes (FM), which was recently reported to have a role in drug transport, in nutrient uptake remains unknown. OBJECTIVES This study determined nutrient transport expression in human FM and FM cells and compared expression with placental tissues and BeWo cells. METHODS RNA sequencing (RNA-Seq) of placental and FM tissues and cells was done. Genes of major solute transporter groups, such as SLC and ABC, were identified. Proteomic analysis of cell lysates was performed via nano-liquid chromatography-tandem mass spectrometry (nanoLC-MS/MS) to confirm expression at a protein level. RESULTS We determined that FM tissues and cells derived from the fetal membrane tissues express nutrient transporter genes, and their expression is similar to that seen in the placenta or BeWo cells. In particular, transporters involved in macronutrient and micronutrient transfer were identified in both placental and FM cells. Consistent with RNA-Seq findings, carbohydrate transporters (3), vitamin transport-related proteins (8), amino acid transporters (21), fatty acid transport-related proteins (9), cholesterol transport-related proteins (6) and nucleoside transporters (3) were identified in BeWo and FM cells, with both groups sharing similar nutrient transporter expression. CONCLUSION This study determined the expression of nutrient transporters in human FMs. This knowledge is the first step in improving our understanding of nutrient uptake kinetics during pregnancy. Functional studies are required to determine the properties of nutrient transporters in human FMs.
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Affiliation(s)
- Ryan C V Lintao
- Division of Basic Science and Translational Research, Department of Obstetrics & Gynecology, The University of Texas Medical Branch at Galveston, 301 University Blvd., Galveston, TX, 77555-1062, USA; College of Medicine, University of the Philippines Manila, 547 Pedro Gil St., Manila, 1000, Philippines
| | - Ananth Kumar Kammala
- Division of Basic Science and Translational Research, Department of Obstetrics & Gynecology, The University of Texas Medical Branch at Galveston, 301 University Blvd., Galveston, TX, 77555-1062, USA.
| | - Natasha Vora
- Division of Basic Science and Translational Research, Department of Obstetrics & Gynecology, The University of Texas Medical Branch at Galveston, 301 University Blvd., Galveston, TX, 77555-1062, USA; John Sealy School of Medicine, University of Texas Medical Branch at Galveston, 301 University Blvd., Galveston, TX, 77555-1062, USA
| | - Jerome L Yaklic
- Department of Obstetrics & Gynecology, The University of Texas Medical Branch at Galveston, 301 University Blvd., Galveston, TX, 77555-1062, USA
| | - Ramkumar Menon
- Division of Basic Science and Translational Research, Department of Obstetrics & Gynecology, The University of Texas Medical Branch at Galveston, 301 University Blvd., Galveston, TX, 77555-1062, USA.
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Creighton JV, de Souza Gonçalves L, Artioli GG, Tan D, Elliott-Sale KJ, Turner MD, Doig CL, Sale C. Physiological Roles of Carnosine in Myocardial Function and Health. Adv Nutr 2022; 13:1914-1929. [PMID: 35689661 PMCID: PMC9526863 DOI: 10.1093/advances/nmac059] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 04/25/2022] [Accepted: 06/08/2022] [Indexed: 01/28/2023] Open
Abstract
Carnosine is a pleiotropic histidine-containing dipeptide synthesized from β-alanine and l-histidine, with the intact dipeptide and constituent amino acids being available from the diet. The therapeutic application of carnosine in myocardial tissue is promising, with carnosine playing a potentially beneficial role in both healthy and diseased myocardial models. This narrative review discusses the role of carnosine in myocardial function and health, including an overview of the metabolic pathway of carnosine in the myocardial tissue, the roles carnosine may play in the myocardium, and a critical analysis of the literature, focusing on the effect of exogenous carnosine and its precursors on myocardial function. By so doing, we aim to identify current gaps in the literature, thereby identifying considerations for future research.
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Affiliation(s)
- Jade V Creighton
- Musculoskeletal Physiology Research Group, Sport, Health, and Performance Enhancement (SHAPE) Research Centre, School of Science and Technology, Nottingham Trent University, Clifton, Nottingham, United Kingdom
| | | | - Guilherme G Artioli
- Department of Life Sciences, Manchester Metropolitan University, Manchester, United Kingdom
| | - Di Tan
- Natural Alternatives International, Inc., Carlsbad, CA, USA
| | - Kirsty J Elliott-Sale
- Musculoskeletal Physiology Research Group, Sport, Health, and Performance Enhancement (SHAPE) Research Centre, School of Science and Technology, Nottingham Trent University, Clifton, Nottingham, United Kingdom,Department of Sport and Exercise Sciences, Institute of Sport, Manchester Metropolitan University, Manchester, United Kingdom
| | - Mark D Turner
- Centre for Diabetes, Chronic Diseases, and Ageing, School of Science and Technology, Nottingham Trent University, Clifton, Nottingham, United Kingdom
| | - Craig L Doig
- Centre for Diabetes, Chronic Diseases, and Ageing, School of Science and Technology, Nottingham Trent University, Clifton, Nottingham, United Kingdom
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Zhang X, Jiang B, Ji C, Li H, Yang L, Jiang G, Wang Y, Liu G, Liu G, Min L, Zhao F. Quantitative Label-Free Proteomic Analysis of Milk Fat Globule Membrane in Donkey and Human Milk. Front Nutr 2021; 8:670099. [PMID: 34239890 PMCID: PMC8258387 DOI: 10.3389/fnut.2021.670099] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 05/21/2021] [Indexed: 12/11/2022] Open
Abstract
Previous studies have found donkey milk (DM) has the similar compositions with human milk (HM) and could be used as a potential hypoallergenic replacement diet for babies suffering from cow's milk allergy. Milk fat globule membrane (MFGM) proteins are involved in many biological functions, behaving as important indicators of the nutritional quality of milk. In this study, we used label-free proteomics to quantify the differentially expressed MFGM proteins (DEP) between DM (in 4-5 months of lactation) and HM (in 6-8 months of lactation). In total, 293 DEP were found in these two groups. Gene Ontology (GO) enrichment analysis revealed that the majority of DEP participated in regulation of immune system process, membrane invagination and lymphocyte activation. Several significant Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were determined for the DEP, such as lysosome, galactose metabolism and peroxisome proliferator-activated receptor (PPAR) signaling pathway. Our study may provide valuable information in the composition of MFGM proteins in DM and HM, and expand our knowledge of different biological functions between DM and HM.
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Affiliation(s)
- Xinhao Zhang
- College of Animal Science and Technology, Shandong Agricultural University, Taian, China.,National Engineering Research Center for Gelatin-Based Traditional Chinese Medicine, Dong-E E-Jiao Co., Ltd, Liaocheng, China
| | - Bo Jiang
- Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agricultural and Forestry Sciences, Beijing, China
| | - Chuanliang Ji
- National Engineering Research Center for Gelatin-Based Traditional Chinese Medicine, Dong-E E-Jiao Co., Ltd, Liaocheng, China
| | - Haijing Li
- National Engineering Research Center for Gelatin-Based Traditional Chinese Medicine, Dong-E E-Jiao Co., Ltd, Liaocheng, China
| | - Li Yang
- National Engineering Research Center for Gelatin-Based Traditional Chinese Medicine, Dong-E E-Jiao Co., Ltd, Liaocheng, China
| | - Guimiao Jiang
- National Engineering Research Center for Gelatin-Based Traditional Chinese Medicine, Dong-E E-Jiao Co., Ltd, Liaocheng, China
| | - Yantao Wang
- National Engineering Research Center for Gelatin-Based Traditional Chinese Medicine, Dong-E E-Jiao Co., Ltd, Liaocheng, China
| | - Guangyuan Liu
- National Engineering Research Center for Gelatin-Based Traditional Chinese Medicine, Dong-E E-Jiao Co., Ltd, Liaocheng, China
| | - Guiqin Liu
- Shandong Donkey Industry, Technology Collaborative Innovation Center, Liaocheng University, Liaocheng, China
| | - Lingjiang Min
- College of Animal Science and Technology, Qingdao Agricultural University, Qingdao, China
| | - Fuwei Zhao
- National Engineering Research Center for Gelatin-Based Traditional Chinese Medicine, Dong-E E-Jiao Co., Ltd, Liaocheng, China
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Nielsen MMK, Aryal E, Safari E, Mojsoska B, Jenssen H, Prabhala BK. Current State of SLC and ABC Transporters in the Skin and Their Relation to Sweat Metabolites and Skin Diseases. Proteomes 2021; 9:proteomes9020023. [PMID: 34065737 PMCID: PMC8163169 DOI: 10.3390/proteomes9020023] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/11/2021] [Accepted: 05/13/2021] [Indexed: 01/02/2023] Open
Abstract
With a relatively large surface area (2 m2) and 15% of total body mass, the skin forms the largest organ of the human body. The main functions of the skin include regulation of body temperature by insulation or sweating, regulation of the nervous system, regulation of water content, and protection against external injury. To perform these critical functions, the skin encodes genes for transporters responsible for the cellular trafficking of essential nutrients and metabolites to maintain cellular hemostasis. However, the knowledge on the expression, regulation, and function of these transporters is very limited and needs more work to elucidate how these transporters play a role both in disease progression and in healing. Furthermore, SLC and ABC transporters are understudied, and even less studied in skin. There are sparse reports on relation between transporters in skin and sweat metabolites. This mini review focuses on the current state of SLC and ABC transporters in the skin and their relation to sweat metabolites and skin diseases.
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Affiliation(s)
- Marcus M. K. Nielsen
- Institute of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark; (M.M.K.N.); (E.A.)
| | - Eva Aryal
- Institute of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark; (M.M.K.N.); (E.A.)
| | - Elnaz Safari
- Department of Organic Chemistry, Faculty of Chemistry, Urmia University, Urmia 5756151818, Iran;
| | - Biljana Mojsoska
- Institute of Science and Environment, Roskilde University, Universitetsvej 1, 4000 Roskilde, Denmark; (B.M.); (H.J.)
| | - Håvard Jenssen
- Institute of Science and Environment, Roskilde University, Universitetsvej 1, 4000 Roskilde, Denmark; (B.M.); (H.J.)
| | - Bala Krishna Prabhala
- Institute of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark; (M.M.K.N.); (E.A.)
- Correspondence:
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Du J, Zhu S, Lim RR, Chao JR. Proline metabolism and transport in retinal health and disease. Amino Acids 2021; 53:1789-1806. [PMID: 33871679 PMCID: PMC8054134 DOI: 10.1007/s00726-021-02981-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 04/10/2021] [Indexed: 12/11/2022]
Abstract
The retina is one of the most energy-demanding tissues in the human body. Photoreceptors in the outer retina rely on nutrient support from the neighboring retinal pigment epithelium (RPE), a monolayer of epithelial cells that separate the retina and choroidal blood supply. RPE dysfunction or cell death can result in photoreceptor degeneration, leading to blindness in retinal degenerative diseases including some inherited retinal degenerations and age-related macular degeneration (AMD). In addition to having ready access to rich nutrients from blood, the RPE is also supplied with lactate from adjacent photoreceptors. Moreover, RPE can phagocytose lipid-rich outer segments for degradation and recycling on a daily basis. Recent studies show RPE cells prefer proline as a major metabolic substrate, and they are highly enriched for the proline transporter, SLC6A20. In contrast, dysfunctional or poorly differentiated RPE fails to utilize proline. RPE uses proline to fuel mitochondrial metabolism, synthesize amino acids, build the extracellular matrix, fight against oxidative stress, and sustain differentiation. Remarkably, the neural retina rarely imports proline directly, but it uptakes and utilizes intermediates and amino acids derived from proline catabolism in the RPE. Mutations of genes in proline metabolism are associated with retinal degenerative diseases, and proline supplementation is reported to improve RPE-initiated vision loss. This review will cover proline metabolism in RPE and highlight the importance of proline transport and utilization in maintaining retinal metabolism and health.
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Affiliation(s)
- Jianhai Du
- Department of Ophthalmology and Visual Sciences, West Virginia University, Morgantown, WV, 26506, USA. .,Department of Biochemistry, West Virginia University, Morgantown, WV, 26506, USA. .,One Medical Center Dr, WVU Eye Institute, PO Box 9193, Morgantown, WV, 26505, USA.
| | - Siyan Zhu
- Department of Ophthalmology and Visual Sciences, West Virginia University, Morgantown, WV, 26506, USA.,Department of Biochemistry, West Virginia University, Morgantown, WV, 26506, USA
| | - Rayne R Lim
- Department of Ophthalmology, University of Washington, Seattle, WA, 98109, USA
| | - Jennifer R Chao
- Department of Ophthalmology, University of Washington, Seattle, WA, 98109, USA
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Nielsen CU, Pedersen M, Müller S, Kæstel T, Bjerg M, Ulaganathan N, Nielsen S, Carlsen KL, Nøhr MK, Holm R. Inhibitory Effects of 17-α-Ethinyl-Estradiol and 17-β-Estradiol on Transport Via the Intestinal Proton-Coupled Amino Acid Transporter (PAT1) Investigated In Vitro and In Vivo. J Pharm Sci 2020; 110:354-364. [PMID: 32835702 DOI: 10.1016/j.xphs.2020.08.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 08/12/2020] [Accepted: 08/18/2020] [Indexed: 11/24/2022]
Abstract
The proton-coupled amino acid transporter, PAT1, is known to be responsible for intestinal absorption drug substances such as gaboxadol and vigabatrin. The aim of the present study was to investigate, if 17-α-ethinyl-estradiol (E-E2) and 17-β-estradiol (E) inhibit PAT1-mediated intestinal absorption of proline and taurine in vitro in Caco-2 cells and in vivo using Sprague-Dawley rats to assess the potential for taurine-drug interactions. E and E-E2 inhibited the PAT1-mediated uptake of proline and taurine in Caco-2 cells with IC50 values of 10.0-50.0 μM without major effect on other solute carriers such as the taurine transporter (TauT), di/tri-peptide transporter (PEPT1), and serotonin transporter (SERT1). In PAT1-expressing oocytes E and E-E2 were non-translocated inhibitors. In Caco-2 cells, E and E-E2 lowered the maximal uptake capacity of PAT1 in a non-competitive manner. Likewise, the transepithelial permeability of proline and taurine was reduced in presence of E and E-E2. In male Sprague Dawley rats pre-dosed with E-E2 a decreased maximal plasma concentration (Cmax) of taurine and increased the time (tmax) to reach this was indicated, suggesting the possibility for an in vivo effect on the absorption of PAT1 substrates. In conclusion, 17-α-ethinyl-estradiol and 17-β-estradiol were identified as non-translocated and non-competitive inhibitors of PAT1.
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Affiliation(s)
- Carsten Uhd Nielsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
| | - Maria Pedersen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Stefanie Müller
- Department of Pharmacy, Faculty of Health and Medical Sciences, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Thea Kæstel
- Department of Pharmacy, Faculty of Health and Medical Sciences, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Maria Bjerg
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Nithiya Ulaganathan
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Salli Nielsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Krestine Lundgaard Carlsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Martha Kampp Nøhr
- Department of Pharmacy, Faculty of Health and Medical Sciences, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - René Holm
- Drug Product Development, Janssen R&D, Johnson & Johnson, Turnhoutseweg 30, 2340 Beerse, Belgium; Department of Science and Environment, Roskilde University, 4000 Roskilde, Denmark
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Baliou S, Kyriakopoulos AM, Goulielmaki M, Panayiotidis MI, Spandidos DA, Zoumpourlis V. Significance of taurine transporter (TauT) in homeostasis and its layers of regulation (Review). Mol Med Rep 2020; 22:2163-2173. [PMID: 32705197 PMCID: PMC7411481 DOI: 10.3892/mmr.2020.11321] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 07/09/2020] [Indexed: 11/05/2022] Open
Abstract
Taurine (2‑aminoethanesulfonic acid) contributes to homeostasis, mainly through its antioxidant and osmoregulatory properties. Taurine's influx and efflux are mainly mediated through the ubiquitous expression of the sodium/chloride‑dependent taurine transporter, located on the plasma membrane. The significance of the taurine transporter has been shown in various organ malfunctions in taurine‑transporter‑null mice. The taurine transporter differentially responds to various cellular stimuli including ionic environment, electrochemical charge, and pH changes. The renal system has been used as a model to evaluate the factors that significantly determine the regulation of taurine transporter regulation.
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Affiliation(s)
- Stella Baliou
- National Hellenic Research Foundation, 11635 Athens, Greece
| | | | | | - Michalis I Panayiotidis
- Department of Electron Microscopy and Molecular Pathology, The Cyprus Institute of Neurology and Genetics, 2371 Nicosia, Cyprus
| | - Demetrios A Spandidos
- Laboratory of Clinical Virology, Medical School, University of Crete, 71003 Heraklion, Greece
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Dai H, Coleman DN, Hu L, Martinez-Cortés I, Wang M, Parys C, Shen X, Loor JJ. Methionine and arginine supplementation alter inflammatory and oxidative stress responses during lipopolysaccharide challenge in bovine mammary epithelial cells in vitro. J Dairy Sci 2019; 103:676-689. [PMID: 31733877 DOI: 10.3168/jds.2019-16631] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 09/24/2019] [Indexed: 12/13/2022]
Abstract
Mastitis, inflammation of the udder, is one of the most common diseases hampering milk yield of dairy cows. Methionine (Met) and arginine (Arg) are key nutrients with potential to regulate inflammation and oxidative stress. The aim of this study was to evaluate the effect of increased supply of Met and Arg on mRNA and protein abundance associated with innate immune response and redox balance during lipopolysaccharide (LPS) stimulation in primary bovine mammary epithelial cells (BMEC). Primary BMEC (n = 4 replicates per treatment) were pre-incubated for 12 h in media with the following amino acid combinations: ideal profile of amino acids (control; Con), increased Met supply (incMet), increased Arg supply (incArg), and increased supply of Met and Arg (incMetArg). Subsequently, cells were challenged with or without LPS (1 µg/mL) and incubated for 6 h. Data were analyzed as a 2 × 2 × 2 factorial using the MIXED procedure of SAS 9.4 (SAS Institute Inc., Cary, NC). The downregulation of SLC36A1 and SLC7A1 mRNA abundance induced by LPS was attenuated in the incArg cultures. Although challenge with LPS led to lower abundance of proteins related to the antioxidant response (NFE2L2, NQO1, GPX1), lower levels of ATG7, and lower mRNA abundance of GPX3, we found little effect in cultures with incMet or incArg. Cultures with incMet, incArg, or incMetArg led to attenuation of the upregulation of SOD2 and NOS2 induced by LPS. Abundance of phosphorylated p65 (RELA) was greater after LPS stimulation, but the response was attenuated in cultures with incMet. The greater ratio of pRELA to total RELA in responses to LPS was also attenuated in cultures with incMetArg. The greater mRNA abundance of the proinflammatory cytokine IL1B induced by LPS was attenuated in cultures with incMet, and the same trend induced by LPS on CXCL2 was also alleviated in cultures with incArg. Overall, the data suggest that greater supply of Met and Arg alleviated the proinflammatory responses triggered by LPS through controlling the abundance of proinflammatory cytokines and chemokines and activity of NF-κB. Little benefit on oxidative stress induced by LPS challenge in BMEC was detected with greater supply of Met and Arg.
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Affiliation(s)
- H Dai
- College of Veterinary Medicine, Nanjing Agricultural University, 210095 P. R. China; Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois, Urbana 61801
| | - D N Coleman
- Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois, Urbana 61801
| | - L Hu
- Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois, Urbana 61801; College of Animal Science and Technology, Yangzhou University, 225009 P. R. China
| | - I Martinez-Cortés
- Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois, Urbana 61801; Agricultural and Animal Production Department, UAM-Xochimilco, Mexico City 04960
| | - M Wang
- College of Animal Science and Technology, Yangzhou University, 225009 P. R. China
| | - C Parys
- Evonik Nutrition and Care GmbH, Hanau-Wolfgang, 63457, Germany
| | - X Shen
- College of Veterinary Medicine, Nanjing Agricultural University, 210095 P. R. China
| | - J J Loor
- Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois, Urbana 61801.
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12
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Dietary supplementation with arginine and glutamic acid alters the expression of amino acid transporters in skeletal muscle of growing pigs. Amino Acids 2019; 51:1081-1092. [DOI: 10.1007/s00726-019-02748-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Accepted: 05/26/2019] [Indexed: 01/06/2023]
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13
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Zeng N, Prodhan U, D'Souza RF, Ramzan F, Mitchell SM, Sharma P, Knowles SO, Roy NC, Sjödin A, Wagner KH, Milan AM, Cameron-Smith D, Mitchell CJ. Regulation of Amino Acid Transporters and Sensors in Response to a High protein Diet: A Randomized Controlled Trial in Elderly Men. J Nutr Health Aging 2019; 23:354-363. [PMID: 30932134 DOI: 10.1007/s12603-019-1171-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND The mammalian target of rapamycin complex 1 (mTORC1) is fundamental for many cellular processes, yet it is often dysregulated with aging. Increased amino acid (AA) availability is correlated with the expression of AA transporters (AAT) and mTORC1 activity. Although many AA sensors and mediators have been proposed to relay the AA signal to mTORC1, it has not yet been determined if chronic dietary intervention affects the expression of AAT, sensors and mediators and their relationships with mTORC1 activity. OBJECTIVE AND DESIGN This study investigated whether the consumption of a diet containing either the current recommended daily allowance (RDA) of protein intake (0.8 g/kg/d) or twice the RDA (2RDA) for ten weeks affected the expression of targets associated with AA transport, sensing and mTORC1 regulation in 26 older men (70-81 years). METHOD Muscle biopsies were collected before and after the intervention under fasting conditions. Diets were controlled by providing fully prepared meals and snacks. Western blot and quantitative polymerase chain reaction were used to measure protein and gene expression respectively. RESULTS Consumption of 2RDA reduced the protein expression of L-type amino acid transporter 1 (LAT1). However, plasma leucine concentration and basal mTORC1 activity were unaltered. The downregulation of LAT1 did not affect the expression of AA sensors and mediators, including leucyl tRNA synthetase (LRS), cytosolic arginine sensor for mTORC1 (CASTOR1), Sestrin2 and Rag proteins. Instead, total ribosomal protein S6 (RPS6) was upregulated with 2RDA. CONCLUSION Ten weeks of 2RDA diet did not affect the fasting mTORC1 signaling, but increased total RPS6 might suggest improved muscular translational capacity to maintain muscular mass.
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Affiliation(s)
- N Zeng
- Dr. Cameron Mitchell Faculty of Education | School of Kinesiology, The University of British Columbia | Vancouver Campus, 2553 Wesbrook Mall | Vancouver British Columbia | V6T 1Z3 Canada, Phone 604 827 2072| Cell 604 790 3815,
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14
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Zhao L, Ji X, Zhang X, Li L, Jin Y, Liu W. FLCN is a novel Rab11A-interacting protein that is involved in the Rab11A-mediated recycling transport. J Cell Sci 2018; 131:jcs.218792. [PMID: 30446510 DOI: 10.1242/jcs.218792] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 11/02/2018] [Indexed: 12/23/2022] Open
Abstract
The Birt-Hogg-Dubé (BHD) syndrome related protein FLCN has recently been implicated in the vesicular trafficking processes by interacting with several Rab family GTPases. In the previous studies, we have shown that FLCN could inhibit the binding of overexpressed PAT1, which is a membrane-bound amino acid transporter, to the lysosome in human embryonic kidney 293 cells. This tends to stabilize the lysosomal amino acid pool that is a critical signal to activate the mTORC1 signaling pathway. However, the mechanisms of FLCN during this process remain unexplored. Here we report that FLCN can bind through its C-terminal DENN-like domain to the recycling transport regulator, Rab11A. Suppression of either Rab11A or FLCN facilitated the localization of the overexpressed PAT1 to the lysosome and inhibited its targeting on the plasma membrane. As a consequence, the mTORC1 was down-regulated. The in vitro GEF activity assay does not support FLCN modifies the Rab11A activity directly. Instead, we found FLCN promoted the loading of PAT1 on Rab11A. Our data uncover a function of FLCN in the Rab11A-mediated recycling pathway and might provide new clues to understand BHD.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Lingling Zhao
- Key Laboratory of Animal Biotechnology, the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China 712100
| | - Xin Ji
- Key Laboratory of Animal Biotechnology, the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China 712100
| | - Xiangxiang Zhang
- Key Laboratory of Animal Biotechnology, the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China 712100
| | - Lin Li
- Key Laboratory of Animal Biotechnology, the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China 712100
| | - Yaping Jin
- Key Laboratory of Animal Biotechnology, the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China 712100
| | - Wei Liu
- Key Laboratory of Animal Biotechnology, the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China 712100
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15
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Zhao L, Zhang X, Ji X, Jin Y, Liu W. The amino acid transporter PAT1 regulates mTORC1 in a nutrient-sensitive manner that requires its transport activity. Cell Signal 2018; 53:59-67. [PMID: 30253187 DOI: 10.1016/j.cellsig.2018.09.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 09/17/2018] [Accepted: 09/21/2018] [Indexed: 10/28/2022]
Abstract
The proton-coupled amino acid transporter PAT1 has been postulated to regulate the amino acid-stimulated mTORC1 through two different mechanisms, either it activates mTORC1 by sensing and transducing the lysosomal amino acid signal to mTORC1, or it inhibits mTORC1 by decreasing the signal level, as increased PAT1 has been shown to either activate or inactivate mTORC1 in the human embryonic kidney HEK293 cells. The current study aims to clarify the cause of these controversial observations, which is promoted by the recent discovery that the lysosomal PAT1 can be induced by starvation. Here, we show that under the normal culture condition, overexpression of PAT1 did not apparently change the mTORC1 activity in the fast proliferating cells. However when these cells were synchronized by starvation, followed by nutrient replenishment for a short period of time, the mTORC1 activity was decreased by PAT1 overexpression; if the nutrient stimulation lasted for longer time, the mTORC1 activities could be recovered in the PAT1-overexpressing cells. In addition, we showed the starvation-induced lysosomal PAT1 was gradually decreased during the nutrient replenishment. These results reveal that the influence of PAT1 on mTORC1 seems to be affected by the nutrient condition and the level of lysosomal PAT1. We further demonstrate that suppressing the transport activity of PAT1 abolished its inhibitory effect on mTORC1. Our data support a mechanism that PAT1 can negatively regulate mTORC1 by controlling the cellular nutrient signal level.
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Affiliation(s)
- Lingling Zhao
- Key Laboratory of Animal Biotechnology, the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Xiangxiang Zhang
- Key Laboratory of Animal Biotechnology, the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Xin Ji
- Key Laboratory of Animal Biotechnology, the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling 712100, Shaanxi, China
| | - Yaping Jin
- Key Laboratory of Animal Biotechnology, the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling 712100, Shaanxi, China.
| | - Wei Liu
- Key Laboratory of Animal Biotechnology, the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling 712100, Shaanxi, China.
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Ji X, Zhao L, Luo H, Zhang X, Jin Y, Liu W. Amino acids suppress the expression of PAT1 on lysosomes via inducing the cleavage of a targeting signal. FEBS Lett 2017; 591:2279-2289. [PMID: 28670736 DOI: 10.1002/1873-3468.12738] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 06/19/2017] [Accepted: 06/21/2017] [Indexed: 11/11/2022]
Abstract
The lysosome-associated transporter proton-coupled amino acid transporter 1 (PAT1) promotes nutrient recycling through releasing luminal amino acids into the cytosol. Using HEK293 cells expressing an EGFP-tagged PAT1 (EGFP-PAT1) as a model, we identified a consensus tyrosine-based targeting signal in the cytosolic N-terminal region of PAT1, which facilitates its expression on the lysosome. Interestingly, this signal can be removed via protein cleavage in an amino acid-sensitive manner. The cleavage is suppressed upon amino acid starvation and is induced by amino acid replenishment. However, amino acid deficiency does not suppress the cleavage of amino acid-binding mutants of EGFP-PAT1. Our data support a mechanism, whereby amino acid binding induces PAT1 cleavage to remove a targeting signal, thus suppressing the expression of PAT1 on the lysosome.
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Affiliation(s)
- Xin Ji
- Key Laboratory of Animal Biotechnology, the Ministry of Agriculture, College of Veterinary Medicine, Northwest Agriculture & Forest University, Yangling, Shaanxi, China
| | - Lingling Zhao
- Key Laboratory of Animal Biotechnology, the Ministry of Agriculture, College of Veterinary Medicine, Northwest Agriculture & Forest University, Yangling, Shaanxi, China
| | - Hongjie Luo
- Key Laboratory of Animal Biotechnology, the Ministry of Agriculture, College of Veterinary Medicine, Northwest Agriculture & Forest University, Yangling, Shaanxi, China
| | - Xiangxiang Zhang
- Key Laboratory of Animal Biotechnology, the Ministry of Agriculture, College of Veterinary Medicine, Northwest Agriculture & Forest University, Yangling, Shaanxi, China
| | - Yaping Jin
- Key Laboratory of Animal Biotechnology, the Ministry of Agriculture, College of Veterinary Medicine, Northwest Agriculture & Forest University, Yangling, Shaanxi, China
| | - Wei Liu
- Key Laboratory of Animal Biotechnology, the Ministry of Agriculture, College of Veterinary Medicine, Northwest Agriculture & Forest University, Yangling, Shaanxi, China
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17
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Luo H, Zhao L, Ji X, Zhang X, Jin Y, Liu W. Glycosylation affects the stability and subcellular distribution of human PAT1 protein. FEBS Lett 2017; 591:613-623. [PMID: 28117901 DOI: 10.1002/1873-3468.12567] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 01/13/2017] [Accepted: 01/18/2017] [Indexed: 01/12/2023]
Abstract
The amino acid transporter PAT1 is typically expressed on the lysosome and plasma membranes in various human tissues. Glycosylation has been shown to be critical for the cell surface expression of PAT1, but not for its stability, in Xenopus oocytes. Here, we report that the glycosylation-deficient mutant of PAT1 (PAT13NQ ) is unstable and is degraded mainly via the endoplasmic reticulum-associated degradation pathway in HEK293 cells. Interestingly, PAT13NQ binds preferentially to the plasma membrane rather than to the lysosome. Consistent with this altered distribution, overexpression of PAT13NQ fails to inhibit the mechanistic target of rapamycin complex 1 (mTORC1). Our data suggest that glycosylation affects the stability and localization of PAT1 in HEK293 cells and the subcellular distribution of PAT1 is a factor affecting mTORC1 activity.
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Affiliation(s)
- Hongjie Luo
- Key Laboratory of Animal Biotechnology, College of Veterinary Medicine, The Ministry of Agriculture, Northwest Agriculture & Forest University, Yangling, China
| | - Lingling Zhao
- Key Laboratory of Animal Biotechnology, College of Veterinary Medicine, The Ministry of Agriculture, Northwest Agriculture & Forest University, Yangling, China
| | - Xin Ji
- Key Laboratory of Animal Biotechnology, College of Veterinary Medicine, The Ministry of Agriculture, Northwest Agriculture & Forest University, Yangling, China
| | - Xiangxiang Zhang
- Key Laboratory of Animal Biotechnology, College of Veterinary Medicine, The Ministry of Agriculture, Northwest Agriculture & Forest University, Yangling, China
| | - Yaping Jin
- Key Laboratory of Animal Biotechnology, College of Veterinary Medicine, The Ministry of Agriculture, Northwest Agriculture & Forest University, Yangling, China
| | - Wei Liu
- Key Laboratory of Animal Biotechnology, College of Veterinary Medicine, The Ministry of Agriculture, Northwest Agriculture & Forest University, Yangling, China
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18
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Lambert IH, Kristensen DM, Holm JB, Mortensen OH. Physiological role of taurine--from organism to organelle. Acta Physiol (Oxf) 2015; 213:191-212. [PMID: 25142161 DOI: 10.1111/apha.12365] [Citation(s) in RCA: 214] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 08/01/2014] [Accepted: 08/13/2014] [Indexed: 12/21/2022]
Abstract
Taurine is often referred to as a semi-essential amino acid as newborn mammals have a limited ability to synthesize taurine and have to rely on dietary supply. Taurine is not thought to be incorporated into proteins as no aminoacyl tRNA synthetase has yet been identified and is not oxidized in mammalian cells. However, taurine contributes significantly to the cellular pool of organic osmolytes and has accordingly been acknowledged for its role in cell volume restoration following osmotic perturbation. This review describes taurine homeostasis in cells and organelles with emphasis on taurine biophysics/membrane dynamics, regulation of transport proteins involved in active taurine uptake and passive taurine release as well as physiological processes, for example, development, lung function, mitochondrial function, antioxidative defence and apoptosis which seem to be affected by a shift in the expression of the taurine transporters and/or the cellular taurine content.
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Affiliation(s)
- I. H. Lambert
- Section of Cellular and Developmental Biology; Department of Biology; University of Copenhagen; Copenhagen Ø Denmark
| | - D. M. Kristensen
- Section of Genomics and Molecular Biomedicine; Department of Biology; University of Copenhagen; Copenhagen Denmark
- Cellular and Metabolic Research Section; Department of Biomedical Sciences; Panum Institute; University of Copenhagen; Copenhagen N Denmark
| | - J. B. Holm
- Section of Genomics and Molecular Biomedicine; Department of Biology; University of Copenhagen; Copenhagen Denmark
| | - O. H. Mortensen
- Cellular and Metabolic Research Section; Department of Biomedical Sciences; Panum Institute; University of Copenhagen; Copenhagen N Denmark
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