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Cosetta R, Michela C, Anna V, Mattia D, Elisabetta G, Stefania M. Alternative method to visualize receptor dynamics in cell membranes. PLoS One 2024; 19:e0304172. [PMID: 38861534 PMCID: PMC11166301 DOI: 10.1371/journal.pone.0304172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 05/08/2024] [Indexed: 06/13/2024] Open
Abstract
There is a close relation between membrane receptor dynamics and their behavior. Several microscopy techniques have been developed to study protein dynamics in live cells such as the Fluorescence Recovery After Photobleaching (FRAP) or the Single Particle Tracking (SPT). These methodologies require expensive instruments, are time consuming, allow the analysis of small portion of the cell or an extremely small number of receptors at a time. Here we propose a time-saving approach that allows to visualize the entire receptor pool and its localization in time. This protocol requires an epifluorescence microscope equipped for structured illuminated sectioning and for live cell imaging. It can be applied to characterize membrane receptor and multi protein complex and their response to activators or inhibitors. Image acquisition and analysis can be performed in two days, while cells and substratum preparation require a few minutes a day for three days.
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Affiliation(s)
- Ravelli Cosetta
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
- The Mechanobiology Research Center, UNIBS, Brescia, Italy
| | - Corsini Michela
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
- The Mechanobiology Research Center, UNIBS, Brescia, Italy
| | - Ventura Anna
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Domenichini Mattia
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Grillo Elisabetta
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
- The Mechanobiology Research Center, UNIBS, Brescia, Italy
| | - Mitola Stefania
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
- The Mechanobiology Research Center, UNIBS, Brescia, Italy
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2
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Benedetti A, Turco C, Gallo E, Daralioti T, Sacconi A, Pulito C, Donzelli S, Tito C, Dragonetti M, Perracchio L, Blandino G, Fazi F, Fontemaggi G. ID4-dependent secretion of VEGFA enhances the invasion capability of breast cancer cells and activates YAP/TAZ via integrin β3-VEGFR2 interaction. Cell Death Dis 2024; 15:113. [PMID: 38321003 PMCID: PMC10847507 DOI: 10.1038/s41419-024-06491-2] [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: 06/30/2023] [Revised: 01/19/2024] [Accepted: 01/23/2024] [Indexed: 02/08/2024]
Abstract
Understanding the mechanisms of breast cancer cell communication underlying cell spreading and metastasis formation is fundamental for developing new therapies. ID4 is a proto-oncogene overexpressed in the basal-like subtype of triple-negative breast cancer (TNBC), where it promotes angiogenesis, cancer stem cells, and BRACA1 misfunction. Here, we show that ID4 expression in BC cells correlates with the activation of motility pathways and promotes the production of VEGFA, which stimulates the interaction of VEGFR2 and integrin β3 in a paracrine fashion. This interaction induces the downstream focal adhesion pathway favoring migration, invasion, and stress fiber formation. Furthermore, ID4/ VEGFA/ VEGFR2/ integrin β3 signaling stimulates the nuclear translocation and activation of the Hippo pathway member's YAP and TAZ, two critical executors for cancer initiation and progression. Our study provides new insights into the oncogenic roles of ID4 in tumor cell migration and YAP/TAZ pathway activation, suggesting VEGFA/ VEGFR2/ integrin β3 axis as a potential target for BC treatment.
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Affiliation(s)
- Anna Benedetti
- Translational Oncology Research Unit, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Chiara Turco
- Translational Oncology Research Unit, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Enzo Gallo
- Department of Pathology, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Theodora Daralioti
- Department of Pathology, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Andrea Sacconi
- Biostatistics and Bioinformatics Unit, Clinical Trial Center, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Claudio Pulito
- Translational Oncology Research Unit, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Sara Donzelli
- Translational Oncology Research Unit, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Claudia Tito
- Department of Anatomical, Histological, Forensic & Orthopaedic Sciences, Section of Histology & Medical Embryology, Sapienza University of Rome, Rome, Italy
| | - Martina Dragonetti
- Translational Oncology Research Unit, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Letizia Perracchio
- Department of Pathology, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Giovanni Blandino
- Translational Oncology Research Unit, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Francesco Fazi
- Department of Anatomical, Histological, Forensic & Orthopaedic Sciences, Section of Histology & Medical Embryology, Sapienza University of Rome, Rome, Italy.
| | - Giulia Fontemaggi
- Translational Oncology Research Unit, IRCCS Regina Elena National Cancer Institute, Rome, Italy.
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3
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Serpelloni M, Arricca M, Ravelli C, Grillo E, Mitola S, Salvadori A. Mechanobiology of the relocation of proteins in advecting cells: in vitro experiments, multi-physics modeling, and simulations. Biomech Model Mechanobiol 2023:10.1007/s10237-023-01717-2. [PMID: 37067608 PMCID: PMC10366044 DOI: 10.1007/s10237-023-01717-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 03/29/2023] [Indexed: 04/18/2023]
Abstract
Cell motility-a cellular behavior of paramount relevance in embryonic development, immunological response, metastasis, or angiogenesis-demands a mechanical deformation of the cell membrane and influences the surface motion of molecules and their biochemical interactions. In this work, we develop a fully coupled multi-physics model able to capture and predict the protein flow on endothelial advecting plasma membranes. The model has been validated against co-designed in vitro experiments. The complete picture of the receptor dynamics has been understood, and limiting factors have been identified together with the laws that regulate receptor polarization. This computational approach might be insightful in the prediction of endothelial cell behavior in different tumoral environments, circumventing the time-consuming and expensive empirical characterization of each tumor.
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Affiliation(s)
- M Serpelloni
- The Mechanobiology research center, UNIBS, 25123, Brescia, Italy
- Department of Mechanical and Industrial Engineering, Università degli Studi di Brescia, 25123, Brescia, Italy
| | - M Arricca
- The Mechanobiology research center, UNIBS, 25123, Brescia, Italy
- Department of Mechanical and Industrial Engineering, Università degli Studi di Brescia, 25123, Brescia, Italy
| | - C Ravelli
- The Mechanobiology research center, UNIBS, 25123, Brescia, Italy
- Department of Molecular and Translational Medicine, Università degli Studi di Brescia, 25123, Brescia, Italy
| | - E Grillo
- The Mechanobiology research center, UNIBS, 25123, Brescia, Italy
- Department of Molecular and Translational Medicine, Università degli Studi di Brescia, 25123, Brescia, Italy
| | - S Mitola
- The Mechanobiology research center, UNIBS, 25123, Brescia, Italy
- Department of Molecular and Translational Medicine, Università degli Studi di Brescia, 25123, Brescia, Italy
| | - A Salvadori
- The Mechanobiology research center, UNIBS, 25123, Brescia, Italy.
- Department of Mechanical and Industrial Engineering, Università degli Studi di Brescia, 25123, Brescia, Italy.
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4
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Arricca M, Salvadori A, Bonanno C, Serpelloni M. Modeling Receptor Motility along Advecting Lipid Membranes. MEMBRANES 2022; 12:membranes12070652. [PMID: 35877855 PMCID: PMC9317916 DOI: 10.3390/membranes12070652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 06/21/2022] [Accepted: 06/21/2022] [Indexed: 11/24/2022]
Abstract
This work aims to overview multiphysics mechanobiological computational models for receptor dynamics along advecting cell membranes. Continuum and statistical models of receptor motility are the two main modeling methodologies identified in reviewing the state of the art. Within the former modeling class, a further subdivision based on different biological purposes and processes of proteins’ motion is recognized; cell adhesion, cell contractility, endocytosis, and receptor relocations on advecting membranes are the most relevant biological processes identified in which receptor motility is pivotal. Numerical and/or experimental methods and approaches are highlighted in the exposure of the reviewed works provided by the literature, pertinent to the topic of the present manuscript. With a main focus on the continuum models of receptor motility, we discuss appropriate multiphyisics laws to model the mass flux of receptor proteins in the reproduction of receptor relocation and recruitment along cell membranes to describe receptor–ligand chemical interactions, and the cell’s structural response. The mass flux of receptor modeling is further supported by a discussion on the methodology utilized to evaluate the protein diffusion coefficient developed over the years.
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Affiliation(s)
- Matteo Arricca
- The Mechanobiology Research Center, University of Brescia (UNIBS), 25123 Brescia, Italy; (M.A.); (C.B.); (M.S.)
- Department of Mechanical and Industrial Engineering, Università degli Studi di Brescia, via Branze 38, 25123 Brescia, Italy
| | - Alberto Salvadori
- The Mechanobiology Research Center, University of Brescia (UNIBS), 25123 Brescia, Italy; (M.A.); (C.B.); (M.S.)
- Department of Mechanical and Industrial Engineering, Università degli Studi di Brescia, via Branze 38, 25123 Brescia, Italy
- Correspondence:
| | - Claudia Bonanno
- The Mechanobiology Research Center, University of Brescia (UNIBS), 25123 Brescia, Italy; (M.A.); (C.B.); (M.S.)
- Department of Civil, Environmental, Architectural Engineering and Mathematics, Università degli Studi di Brescia, via Branze 43, 25123 Brescia, Italy
| | - Mattia Serpelloni
- The Mechanobiology Research Center, University of Brescia (UNIBS), 25123 Brescia, Italy; (M.A.); (C.B.); (M.S.)
- Department of Mechanical and Industrial Engineering, Università degli Studi di Brescia, via Branze 38, 25123 Brescia, Italy
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Ingram N, McVeigh LE, Abou-Saleh RH, Batchelor DVB, Loadman PM, McLaughlan JR, Markham AF, Evans SD, Coletta PL. A Single Short 'Tone Burst' Results in Optimal Drug Delivery to Tumours Using Ultrasound-Triggered Therapeutic Microbubbles. Pharmaceutics 2022; 14:pharmaceutics14030622. [PMID: 35335995 PMCID: PMC8953493 DOI: 10.3390/pharmaceutics14030622] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/04/2022] [Accepted: 03/09/2022] [Indexed: 12/10/2022] Open
Abstract
Advanced drug delivery systems, such as ultrasound-mediated drug delivery, show great promise for increasing the therapeutic index. Improvements in delivery by altering the ultrasound parameters have been studied heavily in vitro but relatively little in vivo. Here, the same therapeutic microbubble and tumour type are used to determine whether altering ultrasound parameters can improve drug delivery. Liposomes were loaded with SN38 and attached via avidin: biotin linkages to microbubbles. The whole structure was targeted to the tumour vasculature by the addition of anti-vascular endothelial growth factor receptor 2 antibodies. Tumour drug delivery and metabolism were quantified in SW480 xenografts after application of an ultrasound trigger to the tumour region. Increasing the trigger duration from 5 s to 2 min or increasing the number of 5 s triggers did not improve drug delivery, nor did changing to a chirp trigger designed to stimulate a greater proportion of the microbubble population, although this did show that the short tone trigger resulted in greater release of free SN38. Examination of ultrasound triggers in vivo to improve drug delivery is justified as there are multiple mechanisms at play that may not allow direct translation from in vitro findings. In this setting, a short tone burst gives the best ultrasound parameters for tumoural drug delivery.
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Affiliation(s)
- Nicola Ingram
- Leeds Institute of Medical Research, Faculty of Medicine and Health, St James’s University Hospital, Beckett Street, Leeds LS9 7TF, UK; (L.E.M.); (J.R.M.); (A.F.M.)
- Correspondence: (N.I.); (P.L.C.)
| | - Laura E. McVeigh
- Leeds Institute of Medical Research, Faculty of Medicine and Health, St James’s University Hospital, Beckett Street, Leeds LS9 7TF, UK; (L.E.M.); (J.R.M.); (A.F.M.)
| | - Radwa H. Abou-Saleh
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK; (R.H.A.-S.); (D.V.B.B.); (S.D.E.)
- Nanoscience and Technology Group, Faculty of Science, Galala University, Galala 43711, Egypt
- Department of Physics, Mansoura University, Mansoura 35516, Egypt
| | - Damien V. B. Batchelor
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK; (R.H.A.-S.); (D.V.B.B.); (S.D.E.)
| | - Paul M. Loadman
- Institute of Cancer Therapeutics, University of Bradford, Bradford BD7 1DP, UK;
| | - James R. McLaughlan
- Leeds Institute of Medical Research, Faculty of Medicine and Health, St James’s University Hospital, Beckett Street, Leeds LS9 7TF, UK; (L.E.M.); (J.R.M.); (A.F.M.)
- School of Electronic and Electrical Engineering, University of Leeds, Leeds LS2 9JT, UK
| | - Alexander F. Markham
- Leeds Institute of Medical Research, Faculty of Medicine and Health, St James’s University Hospital, Beckett Street, Leeds LS9 7TF, UK; (L.E.M.); (J.R.M.); (A.F.M.)
| | - Stephen D. Evans
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK; (R.H.A.-S.); (D.V.B.B.); (S.D.E.)
| | - P. Louise Coletta
- Leeds Institute of Medical Research, Faculty of Medicine and Health, St James’s University Hospital, Beckett Street, Leeds LS9 7TF, UK; (L.E.M.); (J.R.M.); (A.F.M.)
- Correspondence: (N.I.); (P.L.C.)
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6
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Li Z, Li JN, Li Q, Liu C, Zhou LH, Zhang Q, Xu Y. miR-25-5p regulates endothelial progenitor cell differentiation in response to shear stress through targeting ABCA1. Cell Biol Int 2021; 45:1876-1886. [PMID: 33945659 DOI: 10.1002/cbin.11621] [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: 12/02/2020] [Revised: 04/07/2021] [Accepted: 05/01/2021] [Indexed: 11/10/2022]
Abstract
The importance of flow shear stress (SS) on the differentiation of endothelial progenitor cells (EPCs) has been demonstrated in various studies. Cholesterol retention and microRNA regulation have been also proposed as relevant factors involved in this process, though evidence regarding their regulatory roles in the differentiation of EPCs is currently lacking. In the present study on high shear stress (HSS)-induced differentiation of EPCs, we investigated the importance of ATP-binding cassette transporter 1 (ABCA1), an important regulator in cholesterol efflux, and miR-25-5p, a potential regulator of endothelial reconstruction. We first revealed an inverse correlation between miR-25-5p and ABCA1 expression levels in EPCs under HSS treatment; their direct interaction was subsequently validated by a dual-luciferase reporter assay. Further studies using flow cytometry and quantitative polymerase chain reaction demonstrated that both miR-25-5p overexpression and ABCA1 inhibition led to elevated levels of specific markers of endothelial cells, with concomitant downregulation of smooth muscle cell markers. Finally, knockdown of ABCA1 in EPCs significantly promoted tube formation, which confirmed our conjecture. Our current results suggest that miR-25-5p might regulate the differentiation of EPCs partially through targeting ABCA1, and such a mechanism might account for HSS-induced differentiation of EPCs.
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Affiliation(s)
- Zhe Li
- Department of Cerebrovascular Diseases, Blue Cross Brain Hospital affiliated to Tongji University, Shanghai, China
| | - Jia-Nan Li
- Department of Neurosurgery, General Hospital of Northern Theater Command, Shenyang, Liaoning, China
| | - Qiang Li
- Department of Neurosurgery, Changhai Hospital of Shanghai affiliated to Naval Military Medical University, Shanghai, China
| | - Chun Liu
- Department of Cerebrovascular Diseases, Blue Cross Brain Hospital affiliated to Tongji University, Shanghai, China
| | - Lin-Hua Zhou
- Department of Cerebrovascular Diseases, Blue Cross Brain Hospital affiliated to Tongji University, Shanghai, China
| | - Qi Zhang
- Department of Cerebrovascular Diseases, Blue Cross Brain Hospital affiliated to Tongji University, Shanghai, China
| | - Yi Xu
- Department of Neurosurgery, Changhai Hospital of Shanghai affiliated to Naval Military Medical University, Shanghai, China
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7
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Quantifying the adhesive strength between the SARS-CoV-2 S-proteins and human receptor and its effect in therapeutics. Sci Rep 2020; 10:17538. [PMID: 33067518 PMCID: PMC7568573 DOI: 10.1038/s41598-020-74189-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 09/21/2020] [Indexed: 12/21/2022] Open
Abstract
The binding affinity and adhesive strength between the spike (S) glycoproteins of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and the human angiotensin-converting enzyme 2 (ACE2) receptor is computed using molecular dynamics (MD) simulations. The calculations indicate that the binding affinity is [Formula: see text] [Formula: see text] with a maximum adhesive force of [Formula: see text] pN. Our analysis suggests that only 27 (13 in S-protein, 14 in ACE2) residues are active during the initial fusion process between the S-protein and ACE2 receptor. With these insights, we investigated the effect of possible therapeutics in the size and wrapping time of virus particles by reducing the binding energy. Our analysis indicates that this energy has to be reduced significantly, around 50% or more, to block SARS-CoV-2 particles with radius in the order of [Formula: see text] nm. Our study provides concise target residues and target binding energy reduction between S-proteins and receptors for the development of new therapeutics treatments for COVID-19 guided by computational design.
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8
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Grillo E, Corsini M, Ravelli C, di Somma M, Zammataro L, Monti E, Presta M, Mitola S. A novel variant of VEGFR2 identified by a pan-cancer screening of recurrent somatic mutations in the catalytic domain of tyrosine kinase receptors enhances tumor growth and metastasis. Cancer Lett 2020; 496:84-92. [PMID: 33035615 DOI: 10.1016/j.canlet.2020.09.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/18/2020] [Accepted: 09/25/2020] [Indexed: 01/10/2023]
Abstract
In cancer genomics, recurrence of mutations in gene families that share homologous domains has recently emerged as a reliable indicator of functional impact and can be exploited to reveal the pro-oncogenic effect of previously uncharacterized variants. Pan-cancer analyses of mutation hotspots in the catalytic domain of a subset of tyrosine kinase receptors revealed that two infrequent mutations of VEGFR2 (R1051Q and D1052N) recur in analogous proteins and correlate with reduced patient survival. Functional validation showed that both R1051Q and D1052N mutations increase the enzymatic activity of VEGFR2. The expression of VEGFR2R1051Q potentiates the PI3K/Akt signaling axis in cancer cells, increasing their tumorigenic potential in vitro and in vivo. In addition, it confers to cancer cells an increased sensitivity to the VEGFR2-targeted tyrosine kinase inhibitor Linifanib. In the context of an efficacious application of anti-cancer targeted therapies, these findings indicate that the screening for uncharacterized mutations, like VEGFR2R1051Q, may help to predict patient prognosis and drug response, with significant clinical implications.
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Affiliation(s)
- Elisabetta Grillo
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, 25123, Italy.
| | - Michela Corsini
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, 25123, Italy
| | - Cosetta Ravelli
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, 25123, Italy; Laboratory for Preventive and Personalized Medicine (MPP Lab), University of Brescia, 25123, Italy
| | - Margherita di Somma
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, 25123, Italy
| | - Luca Zammataro
- Department of Obstetrics, Gynecology and Reproductive Sciences, Yale School of Medicine, New Haven, CT 06510, USA
| | - Eugenio Monti
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, 25123, Italy
| | - Marco Presta
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, 25123, Italy
| | - Stefania Mitola
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, 25123, Italy; Laboratory for Preventive and Personalized Medicine (MPP Lab), University of Brescia, 25123, Italy.
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9
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Amodeo R, Convertino D, Calvello M, Ceccarelli L, Bonsignore F, Ravelli C, Cattaneo A, Martini C, Luin S, Mitola S, Signore G, Marchetti L. Fluorolabeling of the PPTase-Related Chemical Tags: Comparative Study of Different Membrane Receptors and Different Fluorophores in the Labeling Reactions. Front Mol Biosci 2020; 7:195. [PMID: 32850976 PMCID: PMC7426934 DOI: 10.3389/fmolb.2020.00195] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 07/22/2020] [Indexed: 11/13/2022] Open
Abstract
The set-up of an advanced imaging experiment requires a careful selection of suitable labeling strategies and fluorophores for the tagging of the molecules of interest. Here we provide an experimental workflow to allow evaluation of fluorolabeling performance of the chemical tags target of phosphopantetheinyl transferase enzymes (PPTases), once inserted in the sequence of different proteins of interest. First, S6 peptide tag was fused to three different single-pass transmembrane proteins (the tyrosine receptor kinases TrkA and VEGFR2 and the tumor necrosis factor receptor p75NTR), providing evidence that all of them can be conveniently albeit differently labeled. Moreover, we chose the S6-tagged TrkA construct to test eight different organic fluorophores for the PPTase labeling of membrane receptors in living cells. We systematically compared their non-specific internalization when added to a S6-tag negative cell culture, the percentage of S6-TrkA expressing cells effectively labeled and the relative mean fluorescence intensity, their photostability upon conjugation, and ratio of specific (cellular) versus background (glass-adhered) signal. This allowed to identify which fluorophores are actually recommended for these labeling reactions. Finally, we compared the PPTase labeling of a purified, YBBR-tagged Nerve Growth Factor with two differently charged organic dyes. We detected some batch-to-batch variability in the labeling yield, regardless of the fluorophore used. However, upon purification of the fluorescent species and incubation with living primary DRG neurons, no significant difference could be appreciated in both internalization and axonal transport of the labeled neurotrophins.
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Affiliation(s)
- Rosy Amodeo
- NEST, Scuola Normale Superiore, Pisa, Italy.,Center for Nanotechnology Innovation @NEST, Istituto Italiano di Tecnologia, Pisa, Italy
| | - Domenica Convertino
- NEST, Scuola Normale Superiore, Pisa, Italy.,Center for Nanotechnology Innovation @NEST, Istituto Italiano di Tecnologia, Pisa, Italy
| | | | - Lorenzo Ceccarelli
- Center for Nanotechnology Innovation @NEST, Istituto Italiano di Tecnologia, Pisa, Italy.,Dipartimento di Farmacia, Università di Pisa, Pisa, Italy
| | | | - Cosetta Ravelli
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | | | | | - Stefano Luin
- NEST, Scuola Normale Superiore, Pisa, Italy.,CNR-NANO, Pisa, Italy
| | - Stefania Mitola
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Giovanni Signore
- NEST, Scuola Normale Superiore, Pisa, Italy.,Fondazione Pisana per la Scienza Onlus, Pisa, Italy
| | - Laura Marchetti
- Center for Nanotechnology Innovation @NEST, Istituto Italiano di Tecnologia, Pisa, Italy.,Dipartimento di Farmacia, Università di Pisa, Pisa, Italy
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