RNA-Seq of wild-type murine primary cortical neurons co-cultured in a transwell-based system with Mecp2 knock-out or wild-type cortical murine astrocytes
Rett syndrome (RTT; OMIM#312750) is a rare devastating neurodevelopmental disorder that represents the most common genetic cause of severe intellectual disability in girls. Mutations in the X-linked methyl-CpG-binding protein 2 (MECP2) gene have been reported in over 95% cases of classical forms of RTT. Although initial studies supported a role for MeCP2 exclusively in neurons, recent data indicate a function also in astrocytes, which emerged as critical players involved in RTT pathogenesis through non-cell autonomous effects. Indeed, Mecp2 knock-out (KO) astrocytes cannot properly support neuronal maturation of wilt-type (WT) neurons and our data demonstrated a detrimental effect also on synaptogenesis and synaptic maintainence. Nevertheless, the molecular mechanisms by which RTT astrocytes can impact on neuronal health remains unknown. In comparison to previous studies exploring the transcriptomic and proteomic profiles of KO astrocytes per se, we used an indirect strategy to unveil the molecular mechanisms responsible for their negative action on neurons. We thus analysed the molecular pathways deregulated in WT neurons cultivated under the influence of KO (n=8) versus WT (n=7) astrocytes, in a transwell-based co-culture system, that allows the exchange of paracrine signals preventing cell-to-cell contact. Astrocytes were seeded on transwell inserts and transferred on neurons at Div0; the co-cultures were maintained until Div14. WT cortical neurons cultivated alone were also included (n=5).