Methyl-CpG Binding Protein 2 (MeCP2) is Expressed in Embryonic Non-Neuronal Cells and Regulates the Cell Growth
T.Kubota; M.Kunio; N.Kaoru.
Abstract
MeCP2 is a transcriptional repressor protein that binds specifically to methylated CpG sequences on genomic DNA. Heterozygous mutations of this gene cause an autistic child disease, Rett syndrome. MeCP2 has been thought to be expressed exclusively in neurons in the adult brains. Here, we show that MeCP2 is also expressed in non-neuronal (mostly glial) cells in both primary cultured and acutely dissociated cells derived from the embryonic mouse brain. Moreover, siRNA-induced Mecp2 knock-down resulted in the reduction of the living glial cell number in embryonic primary culture detected by MTT assay and the reduction of the cell division rate examined by BrdU incorporation assay. These results suggest that Mecp2 may play important roll for glial cell growth during brain development, and further indicate that defect of MeCP2 in glial cells may contribute to the some features of Rett syndrome, such as microcephaly and mental retardation.
Lay Summary
Glial cells, also know as neuroglia or glia, are non-neuronal cells that provide support and nutrition, provide "housekeeping" duties, and assist in cell-to-cell communication in the nervous system. They are estimated to outnumber neurons by as much as 50 to 1 in the human brain. It has been thought that MeCP2 is expressed exclusively in neurons in the adult brains. Here, contrasting previously published studies, the authors show that MeCP2 is also expressed in embryonic mouse glial cells. Furthermore, they suggest a novel role for MeCP2 - that is, MeCP2 may play important roll for glial cell growth during brain development.