Downregulation of CNPase in a MeCP2 deficient mouse model of Rett syndrome.

OBJECTIVES: To investigate the possible target genes of methyl-CpG-binding protein 2 (MeCP2) that contribute to Rett syndrome (RTT).

METHODS: Brain tissues were taken from Mecp2(308/Y) mice or control mice and then subjected to real-time quantitative reverse transcriptase polymerase chain reaction (RT-PCR), immunohistochemical staining, and Western blot analysis for connexin (Cx)43, Cx45, Cx40, Cx32, 2,3-cyclic nucleotide 3-phosphohydrolase (CNPase), and glial fibrillary acidic protein (GFAP).

RESULTS: The expression of CNPase in subcortical white matter and hippocampi was lower in RTT mice compared to control mice at both mRNA and protein levels. In contrast, the expression of Cx43, Cx40, Cx45, Cx32, or GFAP was not altered in RTT mice compared to control mice.

CONCLUSION: The downregulation of CNPase expression in the brain may be a possible consequence of Mecp2 gene mutation, and the indicated dysfunction of the oligodendrocytes in the subcortical white matter and hippocampi may be involved in RTT pathogenesis.