Generation and Characterization of a Human Neuronal In Vitro Model for Rett Syndrome Using a Direct Reprogramming...

Area of Science:

• Neuroscience
• Genetics
• Cell Biology

Background:

• Rett Syndrome (RTT) is a severe neurodevelopmental disorder caused by mutations in the methyl-CpG-binding protein gene (MECP2).
• Human brain samples from RTT patients are scarce, necessitating in vitro models for studying pathological neuronal changes.
• Direct reprogramming offers a method to generate patient-specific neuronal models.

Purpose of the Study:

• To establish a direct reprogramming method for generating neuronal cells from MeCP2-deficient and wild-type human fibroblasts.
• To validate the neuronal identity and RTT-specific pathological features in the generated cells.
• To assess the therapeutic potential of MeCP2 delivery in the RTT neuronal model.

Main Methods:

• Direct reprogramming of human dermal fibroblasts using SOX2 and PAX6 transcription factors.
• Generation of MeCP2-deficient and wild-type neuronal cells.
• RNA-sequencing to confirm neuronal identity.
• Assessment of dendritic arborization and histone acetylation.
• Treatment with TAT-conjugated MeCP2 to evaluate therapeutic effects.

Main Results:

• Successfully generated functional neurons from MeCP2-deficient and wild-type fibroblasts.
• MeCP2-deficient neurons exhibited diminished dendritic arborization and histone hyperacetylation (H3, H4).
• Treatment with TAT-MeCP2 ameliorated H4K16 hyperacetylation in MeCP2-deficient neurons.
• The model accurately reflects RTT pathophysiology in vitro.

Conclusions:

• Direct reprogramming provides a powerful tool for creating patient-derived neuronal models of Rett Syndrome.
• This in vitro model facilitates the study of RTT disease mechanisms.
• The model is valuable for investigating novel therapeutic strategies for RTT.