TY - JOUR AU - Thalwieser, Zsófia AU - Fonódi, Márton AU - Király, Nikolett AU - Csortos, Csilla AU - Boratkó, Anita TI - PP2A Affects Angiogenesis via Its Interaction with a Novel Phosphorylation Site of TSP1 JF - INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES J2 - INT J MOL SCI VL - 25 PY - 2024 IS - 3 SP - 1844 SN - 1661-6596 DO - 10.3390/ijms25031844 UR - https://m2.mtmt.hu/api/publication/34573513 ID - 34573513 AB - Alterations in angiogenic properties play a pivotal role in the manifestation and onset of various pathologies, including vascular diseases and cancer. Thrombospondin-1 (TSP1) protein is one of the master regulators of angiogenesis. This study unveils a novel aspect of TSP1 regulation through reversible phosphorylation. The silencing of the B55α regulatory subunit of protein phosphatase 2A (PP2A) in endothelial cells led to a significant decrease in TSP1 expression. Direct interaction between TSP1 and PP2A-B55α was confirmed via various methods. Truncated TSP1 constructs were employed to identify the phosphorylation site and the responsible kinase, ultimately pinpointing PKC as the enzyme phosphorylating TSP1 on Ser93. The biological effects of B55α–TSP1 interaction were also analyzed. B55α silencing not only counteracted the increase in TSP1 expression during wound closure but also prolonged wound closure time. Although B55α silenced cells initiated tube-like structures earlier than control cells, their spheroid formation was disrupted, leading to disintegration. Cells transfected with phosphomimic TSP1 S93D exhibited smaller spheroids and reduced effectiveness in tube formation, revealing insights into the effects of TSP1 phosphorylation on angiogenic properties. In this paper, we introduce a new regulatory mechanism of angiogenesis by reversible phosphorylation on TSP1 S93 by PKC and PP2A B55α. LA - English DB - MTMT ER - TY - JOUR AU - Fonódi, Márton AU - Thalwieser, Zsófia AU - Csortos, Csilla AU - Boratkó, Anita TI - TIMAP, a Regulatory Subunit of Protein Phosphatase 1, Inhibits In Vitro Neuronal Differentiation JF - INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES J2 - INT J MOL SCI VL - 24 PY - 2023 IS - 24 SN - 1661-6596 DO - 10.3390/ijms242417360 UR - https://m2.mtmt.hu/api/publication/34430018 ID - 34430018 AB - TIMAP (TGF-β-inhibited membrane associated protein) is abundant in endothelial cells, and it has been regarded as a member of the myosin phosphatase targeting protein (MYPT) family. Our workgroup previously identified several interacting protein partners of TIMAP and proved its regulatory subunit role for protein phosphatase 1 catalytic subunit (PP1c). TIMAP is also expressed in neuronal cells, but details of its function have not been studied yet. Therefore, we aimed to explore the role of TIMAP in neuronal cells, especially during differentiation. Expression of TIMAP was proved both at mRNA and protein levels in SH-SY5Y human neuroblastoma cells. Differentiation of SH-SY5Y cells was optimized and proved by the detection of neuronal differentiation markers, such as β3-tubulin, nestin and inhibitor of differentiation 1 (ID1) using qPCR and Western blot. We found downregulation of TIMAP during differentiation. In accordance with this, overexpression of recombinant TIMAP attenuated the differentiation of neuronal cells. Moreover, the subcellular localization of TIMAP has changed during differentiation as it translocated from the plasma membrane into the nucleus. The nuclear interactome of TIMAP revealed more than 50 proteins, offering the possibility to further investigate the role of TIMAP in several key physiological pathways of neuronal cells. LA - English DB - MTMT ER - TY - JOUR AU - Király, Nikolett AU - Thalwieser, Zsófia AU - Fonódi, Márton AU - Csortos, Csilla AU - Boratkó, Anita TI - Dephosphorylation of annexin A2 by protein phosphatase 1 regulates endothelial cell barrier JF - IUBMB LIFE J2 - IUBMB LIFE VL - 2021 PY - 2021 IS - 73 SP - 1257 EP - 1268 PG - 12 SN - 1521-6543 DO - 10.1002/iub.2538 UR - https://m2.mtmt.hu/api/publication/32124402 ID - 32124402 LA - English DB - MTMT ER - TY - JOUR AU - Király, Nikolett AU - Csortos, Csilla AU - Boratkó, Anita TI - Ser69 phosphorylation of TIMAP affects endothelial cell migration JF - EXPERIMENTAL LUNG RESEARCH J2 - EXP LUNG RES VL - 47 PY - 2021 IS - 7 SP - 334 EP - 343 PG - 10 SN - 0190-2148 DO - 10.1080/01902148.2021.1960651 UR - https://m2.mtmt.hu/api/publication/32124398 ID - 32124398 AB - TIMAP (TGF-β-inhibited membrane-associated protein) is a regulatory subunit of protein phosphatase 1 (PP1). The N-terminal region contains a binding motif for the catalytic subunit of PP1 (PP1c) and a nuclear localization signal (NLS). Phosphorylation of TIMAP on Ser331, Ser333 and Ser337 side chains was shown to regulate the activity of the TIMAP-PP1c complex. Several studies, however, reported an additional side chain of TIMAP. Ser69 is located near to the PP1c binding motif and NLS, therefore, we hypothesized that the phosphorylation of this side chain perhaps may regulate the interaction between TIMAP and PP1c, or may affect the nuclear transport of TIMAP. Materials and Methods: To study the significance of Ser69 phosphorylation, GST-tagged or c-myc-tagged wild type, phosphomimic S69D and phosphonull S69A recombinant TIMAP proteins were expressed in bacteria or endothelial cells, respectively. Protein-protein interactions of the wild type or mutant forms of TIMAP were studied by pull-down and Western blot. Localization of TIMAP S69 mutants in pulmonary artery endothelial cells was detected by immunofluorescent staining and expression and localization of the recombinants were investigated by subcellular fractionation and Western blot. Results: Modifications of Ser69 of TIMAP had no effect on binding of PP1c, ERM or RACK1. However, S69D TIMAP showed enhanced membrane localization and an increased number of membrane protrusions were observed in the cells overexpressing this phosphomimic mutant. Furthermore, significantly faster wound healing and migration rate of the S69D mutant overexpressing cells were detected by endothelial barrier resistance measurements (ECIS). Specific interaction was shown between TIMAP and polo-like kinase 4 (PLK4), a potential kinase to phosphorylate Ser69. Conclusions: Altogether, our results indicate that Ser69 phosphorylation by PLK4 may evoke an enrichment of TIMAP in the plasma membrane region and may play an important role in endothelial cell migration without affecting the PP1c binding ability of TIMAP. LA - English DB - MTMT ER - TY - JOUR AU - Thalwieser, Zsófia AU - Király, Nikolett AU - Fonódi, Márton AU - Csortos, Csilla AU - Boratkó, Anita TI - Protein phosphatase 2A-mediated flotillin-1 dephosphorylation up-regulates endothelial cell migration and angiogenesis regulation JF - JOURNAL OF BIOLOGICAL CHEMISTRY J2 - J BIOL CHEM VL - 294 PY - 2019 IS - 52 SP - 20196 EP - 20206 PG - 11 SN - 0021-9258 DO - 10.1074/jbc.RA119.007980 UR - https://m2.mtmt.hu/api/publication/30929385 ID - 30929385 LA - English DB - MTMT ER - TY - JOUR AU - Boratkó, Anita AU - Csortos, Csilla TI - TIMAP, the versatile protein phosphatase 1 regulator in endothelial cells JF - IUBMB LIFE J2 - IUBMB LIFE VL - 69 PY - 2017 IS - 12 SP - 918 EP - 928 PG - 11 SN - 1521-6543 DO - 10.1002/iub.1695 UR - https://m2.mtmt.hu/api/publication/3291997 ID - 3291997 LA - English DB - MTMT ER - TY - JOUR AU - Boratkó, Anita AU - Csortos, Csilla TI - PKC mediated phosphorylation of TIMAP regulates PP1c activity and endothelial barrier function JF - BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH J2 - BBA-MOL CELL RES VL - 1864 PY - 2017 SP - 431 EP - 439 PG - 9 SN - 0167-4889 DO - 10.1016/j.bbamcr.2016.12.001 UR - https://m2.mtmt.hu/api/publication/3152378 ID - 3152378 LA - English DB - MTMT ER - TY - JOUR AU - Boratkó, Anita AU - Péter, Margit AU - Csortos, Csilla TI - Regulation of merlin by protein phosphataswe 1-TIMAP and EBP50 in endothelial cells JF - INTERNATIONAL JOURNAL OF BIOCHEMISTRY & CELL BIOLOGY J2 - INT J BIOCHEM CELL B VL - 82 PY - 2017 SP - 10 EP - 17 PG - 8 SN - 1357-2725 DO - 10.1016/j.biocel.2016.11.010 UR - https://m2.mtmt.hu/api/publication/3144986 ID - 3144986 N1 - Megosztott első szerző Boratkó A. és Péter M. LA - English DB - MTMT ER - TY - JOUR AU - Veréb, Zoltán AU - Póliska, Szilárd AU - Albert, Réka AU - Olstad, OK AU - Boratkó, Anita AU - Csortos, Csilla AU - Moe, MC AU - Facskó, Andrea AU - Petrovski, Goran TI - Role of human corneal stroma-derived mesenchymal-like stem cells in corneal immunity and wound healing JF - SCIENTIFIC REPORTS J2 - SCI REP VL - 6 PY - 2016 PG - 17 SN - 2045-2322 DO - 10.1038/srep26227 UR - https://m2.mtmt.hu/api/publication/3068290 ID - 3068290 LA - English DB - MTMT ER - TY - JOUR AU - Boratkó, Anita AU - Veréb, Zoltán AU - Petrovski, Goran AU - Csortos, Csilla TI - TIMAP-protein phosphatase 1-complex controls endothelin-1 production via ECE-1 dephosphorylation JF - INTERNATIONAL JOURNAL OF BIOCHEMISTRY & CELL BIOLOGY J2 - INT J BIOCHEM CELL B VL - 73 PY - 2016 SP - 11 EP - 18 PG - 8 SN - 1357-2725 DO - 10.1016/j.biocel.2016.01.016 UR - https://m2.mtmt.hu/api/publication/3015616 ID - 3015616 N1 - Besorolás Név: JOUR idéző Cím: TIMAP-protein phosphatase 1-complex controls endothelin-1 production via ECE-1 dephosphorylation idéző Cím: International Journal of Biochemistry and Cell Biology idéző Folyóirat/Könyv cím/Szabadalmi szám: International Journal of Biochemistry and Cell Biology idéző Kötet: 73 Jelleg Műfaj: JOUR LA - English DB - MTMT ER -