A transcriptional repressor MeCP2 causing Rett syndrome is expressed in embryonic non-neuronal cells and controls their growth.

An epigenetic key protein MeCP2 is thought to be expressed exclusively in mature neurons. Here, we show that MeCP2 is expressed in embryonic non-neuronal cells by immunocytochemistry and Western blotting, and that knockdown of MeCP2 levels using RNA interference reduces their proliferation. These findings suggest that MeCP2 is essential to non-neuronal cell growth during brain development, which may be associated with microcephaly of Rett syndrome patients with MeCP2 mutations.