Modeling RTT Syndrome by iPSC-Derived Neurons from Male and Female Patients with Heterogeneously Severe Hot-Spot MECP2 Variants
Rett syndrome caused by <i>MECP2</i> variants is characterized by a heterogenous clinical spectrum accounted for in 60% of cases by hot-spot variants. Focusing on the most frequent variants, we generated in vitro iPSC-neurons from the blood of RTT girls with p.Arg133Cys and p.Arg255*, as...
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| Format: | Article |
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MDPI AG
2022-11-01
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| Series: | International Journal of Molecular Sciences |
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| Online Access: | https://www.mdpi.com/1422-0067/23/22/14491 |
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| author | Sara Perego Valentina Alari Gianluca Pietra Andrea Lamperti Alessandro Vimercati Nicole Camporeale Maria Garzo Francesca Cogliati Donatella Milani Aglaia Vignoli Angela Peron Lidia Larizza Tommaso Pizzorusso Silvia Russo |
| author_facet | Sara Perego Valentina Alari Gianluca Pietra Andrea Lamperti Alessandro Vimercati Nicole Camporeale Maria Garzo Francesca Cogliati Donatella Milani Aglaia Vignoli Angela Peron Lidia Larizza Tommaso Pizzorusso Silvia Russo |
| author_sort | Sara Perego |
| collection | DOAJ |
| description | Rett syndrome caused by <i>MECP2</i> variants is characterized by a heterogenous clinical spectrum accounted for in 60% of cases by hot-spot variants. Focusing on the most frequent variants, we generated in vitro iPSC-neurons from the blood of RTT girls with p.Arg133Cys and p.Arg255*, associated to mild and severe phenotype, respectively, and of an RTT male harboring the close to p.Arg255*, p.Gly252Argfs*7 variant. Truncated MeCP2 proteins were revealed by Western blot and immunofluorescence analysis. We compared the mutant versus control neurons at 42 days for morphological parameters and at 120 days for electrophysiology recordings, including girls’ isogenic clones. A precocious reduced morphological complexity was evident in neurons with truncating variants, while in p.Arg133Cys neurons any significant differences were observed in comparison with the isogenic wild-type clones. Reduced nuclear size and branch number show up as the most robust biomarkers. Patch clamp recordings on mature neurons allowed the assessment of cell biophysical properties, V-gated currents, and spiking pattern in the mutant and control cells. Immature spiking, altered cell capacitance, and membrane resistance of RTT neurons, were particularly pronounced in the Arg255* and Gly252Argfs*7 mutants. The overall results indicate that the specific markers of in vitro cellular phenotype mirror the clinical severity and may be amenable to drug testing for translational purposes. |
| first_indexed | 2024-03-09T18:16:09Z |
| format | Article |
| id | doaj.art-e58b92889f014013ad53eaa750f24e97 |
| institution | Directory Open Access Journal |
| issn | 1661-6596 1422-0067 |
| language | English |
| last_indexed | 2024-03-09T18:16:09Z |
| publishDate | 2022-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | International Journal of Molecular Sciences |
| spelling | doaj.art-e58b92889f014013ad53eaa750f24e972023-11-24T08:45:17ZengMDPI AGInternational Journal of Molecular Sciences1661-65961422-00672022-11-0123221449110.3390/ijms232214491Modeling RTT Syndrome by iPSC-Derived Neurons from Male and Female Patients with Heterogeneously Severe Hot-Spot MECP2 VariantsSara Perego0Valentina Alari1Gianluca Pietra2Andrea Lamperti3Alessandro Vimercati4Nicole Camporeale5Maria Garzo6Francesca Cogliati7Donatella Milani8Aglaia Vignoli9Angela Peron10Lidia Larizza11Tommaso Pizzorusso12Silvia Russo13Experimental Research Laboratory of Medical Cytogenetics and Molecular Genetics, IRCCS Istituto Auxologico Italiano, Via Ariosto 13, 20145 Milan, ItalyExperimental Research Laboratory of Medical Cytogenetics and Molecular Genetics, IRCCS Istituto Auxologico Italiano, Via Ariosto 13, 20145 Milan, ItalyLaboratory of Biology BIO@SNS, Scuola Normale Superiore, Piazza dei Cavalieri, 7, 56126 Pisa, ItalyExperimental Research Laboratory of Medical Cytogenetics and Molecular Genetics, IRCCS Istituto Auxologico Italiano, Via Ariosto 13, 20145 Milan, ItalyExperimental Research Laboratory of Medical Cytogenetics and Molecular Genetics, IRCCS Istituto Auxologico Italiano, Via Ariosto 13, 20145 Milan, ItalyExperimental Research Laboratory of Medical Cytogenetics and Molecular Genetics, IRCCS Istituto Auxologico Italiano, Via Ariosto 13, 20145 Milan, ItalyExperimental Research Laboratory of Medical Cytogenetics and Molecular Genetics, IRCCS Istituto Auxologico Italiano, Via Ariosto 13, 20145 Milan, ItalyExperimental Research Laboratory of Medical Cytogenetics and Molecular Genetics, IRCCS Istituto Auxologico Italiano, Via Ariosto 13, 20145 Milan, ItalyFondazione IRCCS Ca Granda Ospedale Maggiore, Policlinico, Via Francesco Sforza, 28, 20122 Milan, ItalyDepartment of Health Sciences, Università degli Studi di Milano, Struttura Complessa di Neuropsichiatria dell’Infazia e Adolescenza ASST GOM Niguarda, Piazza Ospedale Maggiore, 3, 20162 Milan, ItalyChild Neuropsychiatry Unit—Epilepsy Center, Department of Health Sciences, ASST Santi Paolo e Carlo, San Paolo Hospital, Università Degli Studi di Milano, 20142 Milan, ItalyExperimental Research Laboratory of Medical Cytogenetics and Molecular Genetics, IRCCS Istituto Auxologico Italiano, Via Ariosto 13, 20145 Milan, ItalyLaboratory of Biology BIO@SNS, Scuola Normale Superiore, Piazza dei Cavalieri, 7, 56126 Pisa, ItalyExperimental Research Laboratory of Medical Cytogenetics and Molecular Genetics, IRCCS Istituto Auxologico Italiano, Via Ariosto 13, 20145 Milan, ItalyRett syndrome caused by <i>MECP2</i> variants is characterized by a heterogenous clinical spectrum accounted for in 60% of cases by hot-spot variants. Focusing on the most frequent variants, we generated in vitro iPSC-neurons from the blood of RTT girls with p.Arg133Cys and p.Arg255*, associated to mild and severe phenotype, respectively, and of an RTT male harboring the close to p.Arg255*, p.Gly252Argfs*7 variant. Truncated MeCP2 proteins were revealed by Western blot and immunofluorescence analysis. We compared the mutant versus control neurons at 42 days for morphological parameters and at 120 days for electrophysiology recordings, including girls’ isogenic clones. A precocious reduced morphological complexity was evident in neurons with truncating variants, while in p.Arg133Cys neurons any significant differences were observed in comparison with the isogenic wild-type clones. Reduced nuclear size and branch number show up as the most robust biomarkers. Patch clamp recordings on mature neurons allowed the assessment of cell biophysical properties, V-gated currents, and spiking pattern in the mutant and control cells. Immature spiking, altered cell capacitance, and membrane resistance of RTT neurons, were particularly pronounced in the Arg255* and Gly252Argfs*7 mutants. The overall results indicate that the specific markers of in vitro cellular phenotype mirror the clinical severity and may be amenable to drug testing for translational purposes.https://www.mdpi.com/1422-0067/23/22/14491Rett syndromehot-spot <i>MECP2</i> pathogenic variantsX inactivation mosaicismgenotype-phenotype correlationiPSC-neuronsearly morphological neuronal biomarkers |
| spellingShingle | Sara Perego Valentina Alari Gianluca Pietra Andrea Lamperti Alessandro Vimercati Nicole Camporeale Maria Garzo Francesca Cogliati Donatella Milani Aglaia Vignoli Angela Peron Lidia Larizza Tommaso Pizzorusso Silvia Russo Modeling RTT Syndrome by iPSC-Derived Neurons from Male and Female Patients with Heterogeneously Severe Hot-Spot MECP2 Variants International Journal of Molecular Sciences Rett syndrome hot-spot <i>MECP2</i> pathogenic variants X inactivation mosaicism genotype-phenotype correlation iPSC-neurons early morphological neuronal biomarkers |
| title | Modeling RTT Syndrome by iPSC-Derived Neurons from Male and Female Patients with Heterogeneously Severe Hot-Spot MECP2 Variants |
| title_full | Modeling RTT Syndrome by iPSC-Derived Neurons from Male and Female Patients with Heterogeneously Severe Hot-Spot MECP2 Variants |
| title_fullStr | Modeling RTT Syndrome by iPSC-Derived Neurons from Male and Female Patients with Heterogeneously Severe Hot-Spot MECP2 Variants |
| title_full_unstemmed | Modeling RTT Syndrome by iPSC-Derived Neurons from Male and Female Patients with Heterogeneously Severe Hot-Spot MECP2 Variants |
| title_short | Modeling RTT Syndrome by iPSC-Derived Neurons from Male and Female Patients with Heterogeneously Severe Hot-Spot MECP2 Variants |
| title_sort | modeling rtt syndrome by ipsc derived neurons from male and female patients with heterogeneously severe hot spot mecp2 variants |
| topic | Rett syndrome hot-spot <i>MECP2</i> pathogenic variants X inactivation mosaicism genotype-phenotype correlation iPSC-neurons early morphological neuronal biomarkers |
| url | https://www.mdpi.com/1422-0067/23/22/14491 |
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