TY - JOUR AU - Mózner, Orsolya AU - Zámbó, Boglárka AU - Bartos, Zsuzsa AU - Gergely, Anna AU - Szabó, Kata Sára AU - Jezsó, Bálint AU - Telbisz, Ágnes Mária AU - Várady, György AU - Homolya, László AU - Hegedűs, Tamás AU - Sarkadi, Balázs TI - Expression, Function and Trafficking of the Human ABCG2 Multidrug Transporter Containing Mutations in an Unstructured Cytoplasmic Loop JF - MEMBRANES (BASEL) J2 - MEMBRANES-BASEL VL - 13 PY - 2023 IS - 10 PG - 14 SN - 2077-0375 DO - 10.3390/membranes13100822 UR - https://m2.mtmt.hu/api/publication/34175360 ID - 34175360 AB - The human ABCG2 multidrug transporter plays a crucial role in the absorption and excretion of xeno- and endobiotics, contributes to cancer drug resistance and the development of gout. In this work, we have analyzed the effects of selected variants, residing in a structurally unresolved cytoplasmic region (a.a. 354–367) of ABCG2 on the function and trafficking of this protein. A cluster of four lysines (K357–360) and the phosphorylation of a threonine (T362) residue in this region have been previously suggested to significantly affect the cellular fate of ABCG2. Here, we report that the naturally occurring K360del variant in human cells increased ABCG2 plasma membrane expression and accelerated cellular trafficking. The variable alanine replacements of the neighboring lysines had no significant effect on transport function, and the apical localization of ABCG2 in polarized cells has not been altered by any of these mutations. Moreover, in contrast to previous reports, we found that the phosphorylation-incompetent T362A, or the phosphorylation-mimicking T362E variants in this loop had no measurable effects on the function or expression of ABCG2. Molecular dynamics simulations indicated an increased mobility of the mutant variants with no major effects on the core structure of the protein. These results may help to decipher the potential role of this unstructured region within this transporter. LA - English DB - MTMT ER - TY - JOUR AU - Pálinkás, Márton AU - Szabó, Edit Zsuzsanna AU - Kulin, Anna AU - Mózner, Orsolya AU - Rásonyi, R. AU - Juhász, Péter AU - Nagy, K. AU - Várady, György AU - Vörös, D. AU - Zámbó, Boglárka AU - Sarkadi, Balázs AU - Poór, Gyula TI - Genetic polymorphisms and decreased protein expression of ABCG2 urate transporters are associated with susceptibility to gout, disease severity and renal-overload hyperuricemia JF - CLINICAL AND EXPERIMENTAL MEDICINE J2 - CLIN EXP MED VL - 23 PY - 2023 IS - 4 SP - 1277 EP - 1284 PG - 8 SN - 1591-8890 DO - 10.1007/s10238-022-00848-7 UR - https://m2.mtmt.hu/api/publication/33061607 ID - 33061607 N1 - National Institute of Locomotor Diseases and Disabilities, Frankel Leo str. 38-40, Budapest, 1023, Hungary Doctoral School of Molecular Medicine, Semmelweis University, Budapest, Hungary Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary Section of Rheumatology and Physiotherapy, Department of Internal Medicine and Haematology, Semmelweis University, Budapest, Hungary Export Date: 9 February 2023 CODEN: CEMLB Correspondence Address: Pálinkás, M.; National Institute of Locomotor Diseases and Disabilities, Frankel Leo str. 38-40, Hungary; email: mrpalinkas@gmail.com Correspondence Address: Poór, G.; Section of Rheumatology and Physiotherapy, Hungary; email: poor.gyula@orfi.hu Funding details: Semmelweis Egyetem, EFOP-3.6.3, VEKOP-16–2017-00009 Funding details: Nemzeti Kutatási Fejlesztési és Innovációs Hivatal, NKFIH, K-128011 Funding details: Nemzeti Kutatási, Fejlesztési és Innovaciós Alap, NKFIA Funding details: Innovációs és Technológiai Minisztérium Funding text 1: Open access funding provided by Semmelweis University. This study has been supported by grants from Hungarian National Development and Innovation Office (NKFIH K-128011 to Gy.V.), FIEK_16-1-2016-0005 (B.S.), and VEKOP-2.1.1-15-2016-00117 (Gy.V.). O.M. was supported by the KDP doctoral scholarship from the Ministry for Innovation and Technology (National Research, Development and Innovation Fund). B.Z. was supported by the Predoctoral Fellowship Grant of Semmelweis University (EFOP-3.6.3.-VEKOP-16–2017-00009). AB - Gout is a common crystal induced disease of high personal and social burden, characterised by severe arthritis and comorbidity if untreated. Impaired function of ABCG2 transporter is causative in gout and may be responsible for renal-overload type hyperuricemia. Despite its importance, there is limited information on how clinical parameters correlate with protein expression and that with genetic changes. Urate and clinical parameters of 78 gouty patients and healthy controls were measured among standardised circumstances from a Hungarian population. ABCG2 membrane expression of red blood cells was determined by flow cytometry-based method and SNPs of this protein were analysed by TaqMan-based qPCR. The prevalence of ABCG2 functional polymorphisms in gouty and control patients were 32.1 and 13.7%, respectively. Most common SNP was Q141K while one sample with R236X, R383C and the lately described M71V were found in the gouty population. These polymorphisms showed strong linkage with decreased protein expression while the latter was also associated with higher fractional urate excretion (FUE) and urinary urate excretion (UUE). This study firstly evaluated ABCG2 protein expression in a clinically defined gouty population while also proving its associations between ABCG2 genetic changes and renal-overload hyperuricemia. The paper also highlighted relations between ABCG2 SNPs, gout susceptibility and disease severity characterised by an early onset disease with frequent flares and tophi formation. LA - English DB - MTMT ER - TY - JOUR AU - Mózner, Orsolya AU - Zámbó, Boglárka AU - Sarkadi, Balázs TI - Modulation of the Human Erythroid Plasma Membrane Calcium Pump (PMCA4b) Expression by Polymorphic Genetic Variants JF - MEMBRANES (BASEL) J2 - MEMBRANES-BASEL VL - 11 PY - 2021 IS - 8 PG - 10 SN - 2077-0375 DO - 10.3390/membranes11080586 UR - https://m2.mtmt.hu/api/publication/32156982 ID - 32156982 AB - In the human ATP2B4 gene, coding for the plasma membrane calcium pump PMCA4b, a minor haplotype results in the decreased expression of this membrane protein in erythroid cells. The presence of this haplotype and the consequently reduced PMCA4b expression have been suggested to affect red blood cell hydration and malaria susceptibility. By using dual-luciferase reporter assays, we have localized the erythroid-specific regulatory region within the haplotype of the ATP2B4 gene, containing predicted GATA1 binding sites that are affected by SNPs in the minor haplotype. Our results show that, in human erythroid cells, the regulation of ATP2B4 gene expression is significantly affected by GATA1 expression, and we document the role of specific SNPs involved in predicted GATA1 binding. Our findings provide a mechanistic explanation at the molecular level for the reduced erythroid-specific PMCA4b expression in carriers of ATP2B4 gene polymorphic variants. LA - English DB - MTMT ER - TY - JOUR AU - Hegedűs, L. AU - Zámbó, Boglárka AU - Pászty, Katalin AU - Padányi, Rita AU - Varga, Karolina AU - Penniston, J.T. AU - Enyedi, Ágnes TI - Molecular Diversity of Plasma Membrane Ca2+ Transporting ATPases: Their Function Under Normal and Pathological Conditions JF - ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY J2 - ADV EXP MED BIOL VL - 1131 PY - 2020 SP - 93 EP - 129 PG - 37 SN - 0065-2598 DO - 10.1007/978-3-030-12457-1_5 UR - https://m2.mtmt.hu/api/publication/30924863 ID - 30924863 AB - Plasma membrane Ca2+ transport ATPases (PMCA1-4, ATP2B1-4) are responsible for removing excess Ca2+ from the cell in order to keep the cytosolic Ca2+ ion concentration at the low level essential for normal cell function. While these pumps take care of cellular Ca2+ homeostasis they also change the duration and amplitude of the Ca2+ signal and can create Ca2+ gradients across the cell. This is accomplished by generating more than twenty PMCA variants each having the character – fast or slow response, long or short memory, distinct interaction partners and localization signals – that meets the specific needs of the particular cell-type in which they are expressed. It has become apparent that these pumps are essential to normal tissue development and their malfunctioning can be linked to different pathological conditions such as certain types of neurodegenerative and heart diseases, hearing loss and cancer. In this chapter we summarize the complexity of PMCA regulation and function under normal and pathological conditions with particular attention to recent developments of the field. © Springer Nature Switzerland AG 2020. LA - English DB - MTMT ER - TY - JOUR AU - Kovacsics, Daniella AU - Brózik, Anna AU - Tihanyi, Borbála AU - Matula, Zsolt AU - Borsy, Adrienn AU - Mészáros, Nikolett AU - Szabó, Edit Zsuzsanna AU - Németh, Eszter AU - Fóthi, Ábel AU - Zámbó, Boglárka AU - Szüts, Dávid AU - Várady, György AU - Orbán, Tamás I. AU - Apáti, Ágota AU - Sarkadi, Balázs TI - Precision-engineered reporter cell lines reveal ABCG2 regulation in live lung cancer cells JF - BIOCHEMICAL PHARMACOLOGY J2 - BIOCHEMIC PHARMACOL VL - 175 PY - 2020 PG - 14 SN - 0006-2952 DO - 10.1016/j.bcp.2020.113865 UR - https://m2.mtmt.hu/api/publication/31240593 ID - 31240593 N1 - Research Centre for Natural Sciences, Institute of Enzymology, Budapest, Hungary South-Pest Hospital Centre, National Institute of Hematology and Infectious Diseases, Laboratory of Molecular and Cytogenetics, Budapest, Hungary Cited By :9 Export Date: 20 October 2022 CODEN: BCPCA Correspondence Address: Sarkadi, B.; Research Centre for Natural Sciences, Rm. D2.03A, Magyar tudósok körútja 2., Hungary; email: sarkadi.balazs@ttk.hu Chemicals/CAS: cisplatin, 15663-27-1, 26035-31-4, 96081-74-2; clemastine, 15686-51-8; cobalt chloride, 1332-82-7, 7646-79-9; colchicine, 64-86-8; dexamethasone, 50-02-2; docetaxel, 114977-28-5; etoposide, 33419-42-0, 433304-61-1; flavopiridol, 131740-09-5, 146426-40-6; gemcitabine, 103882-84-4; hydrocortisone, 50-23-7; methylprednisolone, 6923-42-8, 83-43-2; mitoxantrone, 65271-80-9, 70476-82-3; paclitaxel, 33069-62-4; sodium ion, 17341-25-2; valproic acid, 1069-66-5, 99-66-1; vinblastine, 865-21-4; vorinostat, 149647-78-9; epidermal growth factor receptor, 79079-06-4; ABCG2 protein, human; Antineoplastic Agents; ATP Binding Cassette Transporter, Subfamily G, Member 2; CRISPR-Associated Protein 9; EGFR protein, human; ErbB Receptors; Neoplasm Proteins AB - Expression of the ABCG2 multidrug transporter is a marker of cancer stem cells and a predictor of recurrent malignant disease. Understanding how human ABCG2 expression is modulated by pharmacotherapy is crucial in guiding therapeutic recommendations and may aid rational drug development. Genome edited reporter cells are useful in investigating gene regulation and visualizing protein activity in live cells but require precise targeting to preserve native regulatory regions. Here, we describe a fluorescent reporter assay that allows the noninvasive assessment of ABCG2 regulation in human lung adenocarcinoma cells. Using CRISPR-Cas9 gene editing coupled with homology-directed repair, we targeted an eGFP coding sequence to the translational start site of ABCG2, generating ABCG2 knock-out and in situ tagged ABCG2 reporter cells. Using the engineered cell lines, we show that ABCG2 is upregulated by a number of anti-cancer medications, HDAC inhibitors, hypoxia-mimicking agents and glucocorticoids, supporting a model in which ABCG2 is under the control of a general stress response. To our knowledge, this is the first description of a fluorescent reporter assay system designed to follow the endogenous regulation of a human ABC transporter in live cells. The information gained may guide therapy recommendations and aid rational drug design. LA - English DB - MTMT ER - TY - JOUR AU - Zámbó, Boglárka AU - Mózner, Orsolya AU - Bartos, Zsuzsa AU - Török, György AU - Várady, György AU - Telbisz, Ágnes Mária AU - Homolya, László AU - Orbán, Tamás I. AU - Sarkadi, Balázs TI - Cellular expression and function of naturally occurring variants of the human ABCG2 multidrug transporter JF - CELLULAR AND MOLECULAR LIFE SCIENCES J2 - CELL MOL LIFE SCI VL - 77 PY - 2020 IS - 2 SP - 365 EP - 378 PG - 14 SN - 1420-682X DO - 10.1007/s00018-019-03186-2 UR - https://m2.mtmt.hu/api/publication/30745945 ID - 30745945 N1 - Institute of Enzymology, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar Tudosok krt. 2, Budapest, 1117, Hungary Department of Biophysics and Radiation Biology, Semmelweis University, Tuzolto u. 37-47, Budapest, 1094, Hungary Cited By :16 Export Date: 10 February 2024 CODEN: CMLSF Correspondence Address: Sarkadi, B.; Institute of Enzymology, Magyar Tudosok krt. 2, Hungary; email: sarkadi@biomembrane.hu Chemicals/CAS: adenosine triphosphatase, 37289-25-1, 9000-83-3; ABCG2 protein, human; Adenosine Triphosphatases; ATP Binding Cassette Transporter, Subfamily G, Member 2; Neoplasm Proteins AB - The human ABCG2 multidrug transporter plays a crucial role in the absorption and excretion of xeno- and endobiotics; thus the relatively frequent polymorphic and mutant ABCG2 variants in the population may significantly alter disease conditions and pharmacological effects. Low-level or non-functional ABCG2 expression may increase individual drug toxicity, reduce cancer drug resistance, and result in hyperuricemia and gout. In the present work we have studied the cellular expression, trafficking, and function of nine naturally occurring polymorphic and mutant variants of ABCG2. A comprehensive analysis of the membrane localization, transport, and ATPase activity, as well as retention and degradation in intracellular compartments was performed. Among the examined variants, R147W and R383C showed expression and/or protein folding defects, indicating that they could indeed contribute to ABCG2 functional deficiency. These studies and the applied methods should significantly promote the exploration of the medical effects of these personal variants, promote potential therapies, and help to elucidate the specific role of the affected regions in the folding and function of the ABCG2 protein. © 2019, The Author(s). LA - English DB - MTMT ER - TY - JOUR AU - Mózner, Orsolya AU - Bartos, Zsuzsa AU - Zámbó, Boglárka AU - Homolya, László AU - Hegedűs, Tamás AU - Sarkadi, Balázs TI - Cellular Processing of the ABCG2 Transporter-Potential Effects on Gout and Drug Metabolism. JF - CELLS J2 - CELLS-BASEL VL - 8 PY - 2019 IS - 10 PG - 15 SN - 2073-4409 DO - 10.3390/cells8101215 UR - https://m2.mtmt.hu/api/publication/30924895 ID - 30924895 N1 - Funding Agency and Grant Number: National Research, Development, and Innovation Office [NKFI-127961]; OTKA/NKFIHOrszagos Tudomanyos Kutatasi Alapprogramok (OTKA) [K 128123, NK 115375, FIEK_16-1-2016-0005]; Hungarian Ministry for Innovation and Technology [UNKP-19-3-I-SE-15, UNKP-19-2-I-BME-380] Funding text: This research was funded by National Research, Development, and Innovation Office, grant number NKFI-127961, (T.H.) OTKA/NKFIH grant_K 128123 (L.H.), OTKA/NKFIH grant NK 115375 (B.S.) and FIEK_16-1-2016-0005 (B.S. and L.H.). Z.B. and O.M. were supported by grants UNKP-19-3-I-SE-15 (Z.B.) and UNKP-19-2-I-BME-380 (O.M.) from the Hungarian Ministry for Innovation and Technology. AB - The human ABCG2 is an important plasma membrane multidrug transporter, involved in uric acid secretion, modulation of absorption of drugs, and in drug resistance of cancer cells. Variants of the ABCG2 transporter, affecting cellular processing and trafficking, have been shown to cause gout and increased drug toxicity. In this paper, we overview the key cellular pathways involved in the processing and trafficking of large membrane proteins, focusing on ABC transporters. We discuss the information available for disease-causing polymorphic variants and selected mutations of ABCG2, causing increased degradation and impaired travelling of the transporter to the plasma membrane. In addition, we provide a detailed in silico analysis of an as yet unrecognized loop region of the ABCG2 protein, in which a recently discovered mutation may actually promote ABCG2 membrane expression. We suggest that post-translational modifications in this unstructured loop at the cytoplasmic surface of the protein may have special influence on ABCG2 processing and trafficking. LA - English DB - MTMT ER - TY - JOUR AU - Várady, György AU - Szabó, Edit Zsuzsanna AU - Kulin, Anna AU - Zámbó, Boglárka AU - Mózner, Orsolya AU - Pálinkás, Márton AU - Poór, Gyula AU - Sarkadi, Balázs TI - Potential Diagnostic Application of the Quantitative Assessment of Red Blood Cell Membrane Protein Expression JF - THROMBOSIS AND HAEMOSTASIS: RESEARCH J2 - THROMBOSIS HAEMOSTASIS RES VL - 3 PY - 2019 IS - 2 PG - 5 SN - 2689-9663 UR - https://m2.mtmt.hu/api/publication/31432864 ID - 31432864 LA - English DB - MTMT ER - TY - THES AU - Zámbó, Boglárka TI - Membránfehérjék vizsgálata vörösvértesteken, a kapcsolódó genetikai variánsok azonosítása és jellemzése PY - 2019 DO - 10.14753/SE.2019.2259 UR - https://m2.mtmt.hu/api/publication/30764866 ID - 30764866 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Zámbó, Boglárka AU - Bartos, Zsuzsa AU - Mózner, Orsolya AU - Szabó, Edit Zsuzsanna AU - Várady, György AU - Poór, Gyula AU - Pálinkás, Márton AU - Andrikovics, Hajnalka AU - Hegedűs, Tamás AU - Homolya, László AU - Sarkadi, Balázs TI - Clinically relevant mutations in the ABCG2 transporter uncovered by genetic analysis linked to erythrocyte membrane protein expression JF - SCIENTIFIC REPORTS J2 - SCI REP VL - 8 PY - 2018 IS - 1 PG - 13 SN - 2045-2322 DO - 10.1038/s41598-018-25695-z UR - https://m2.mtmt.hu/api/publication/3370208 ID - 3370208 N1 - Boglárka Zámbó, Zsuzsa Bartos, László Homolya and Balázs Sarkadi contributed equally to this work. AB - The ABCG2 membrane protein is a key xeno- and endobiotic transporter, modulating the absorption and metabolism of pharmacological agents and causing multidrug resistance in cancer. ABCG2 is also involved in uric acid elimination and its impaired function is causative in gout. Analysis of ABCG2 expression in the erythrocyte membranes of healthy volunteers and gout patients showed an enrichment of lower expression levels in the patients. By genetic screening based on protein expression, we found a relatively frequent, novel ABCG2 mutation (ABCG2-M71V), which, according to cellular expression studies, causes reduced protein expression, although with preserved transporter capability. Molecular dynamics simulations indicated a stumbled dynamics of the mutant protein, while ABCG2-M71V expression in vitro could be corrected by therapeutically relevant small molecules. These results suggest that personalized medicine should consider this newly discovered ABCG2 mutation, and genetic analysis linked to protein expression provides a new tool to uncover clinically important mutations in membrane proteins. © 2018 The Author(s). LA - English DB - MTMT ER -