Mecp2, or methyl-CpG binding protein 2, is a transcriptional regulator that binds to methylated genomic DNA. It plays a crucial role in regulating gene expression, neuronal development, and adult synaptic plasticity [1,3,6]. It is also involved in chromatin organization in neurons, with its mutations linked to severe neurodevelopmental disorders [5]. Mouse models have been instrumental in studying Mecp2 functions.

Mutations in Mecp2 are the primary cause of Rett syndrome (RTT), a severe neurological disorder mainly affecting young females [1]. In RTT mouse models, restoring Mecp2 function can reverse neuronal dysfunction, indicating that neurons need the appropriate Mecp2 dose to function properly [4]. Moreover, Mecp2 directly interacts with RNA polymerase II at CpG-rich promoter-proximal regions of many neuronal genes, and patient mutations lead to reduced gene expression, suggesting RTT may be due in part to loss of activity of these genes [2].

In conclusion, Mecp2 is essential for normal neuronal development and function. Studies using mouse models, especially those with Mecp2 knockout or conditional knockout, have provided valuable insights into its role in RTT and other neurodevelopmental disorders, highlighting its potential as a therapeutic target for these conditions.