al analysis Quantitative results are expressed as means 6 standard errors. Student’s t-test was used to compare data, with p,0.05 considered significant. Supporting Information Supporting materials and methods. Author Contributions Conceived and designed the experiments: YO TT. Performed the experiments: YO CM TT. Analyzed the data: YO TT ET. Contributed reagents/materials/analysis tools: KK TM. Wrote the paper: YO TT. expression in wild-type and MeCP2-null astrocytes treated with Glutamate. The astrocytes of each group were References 1. Chahrour M, Zoghbi HY The story of Rett syndrome: from clinic to neurobiology. Neuron 56: 422437. 2. Matsuishi T, Yamashita Y, Takahashi T, Nagamitsu S Rett syndrome: The state of clinical and basic research, and future perspectives. Brain Dev 33: 623631. 3. Amir RE, Van den Veyver IB, Wan M, Tran CQ, Francke U, et al. Rett syndrome is caused by mutations in X-linked MECP2, encoding methyl-CpGbinding protein 2. Nat Genet 23: 185188. 4. Guy J, Hendrich B, Holmes M, Martin JE, Bird A A mouse Mecp2-null mutation causes neurological symptoms that mimic Rett syndrome. Nat Genet 27: 322326. 5. Chen RZ, Akbarian S, Tudor M, Jaenisch R Deficiency of methyl-CpG binding protein-2 in CNS neurons results in a Rett-like phenotype in mice. Nat 20688974 Genet 27: 327331. 6. Calfa G, Percy AK, Pozzo-Miller L Experimental models of Rett syndrome based on Mecp2 dysfunction. Exp Biol Med 236: 319. 7. Bienvenu T, Chelly J Molecular genetics of Rett syndrome: when DNA methylation goes unrecognized. Nat Rev Genet 7: 415426. 8. Saywell V, Viola A, Confort-Gouny S, Le Fur Y, Villard L, et al. Brain magnetic 606143-89-9 resonance study of Mecp2 deletion effects on anatomy and metabolism. Biochem Biophys Res Commun 340: 776783. 9. Ballas N, Lioy DT, Grunseich C, Mandel G Non-cell autonomous influence of MeCP2-deficient glia on neuronal dendritic morphology. Nat Neurosci 12: 311317. 10. Maezawa I, Swanberg S, Harvey D, LaSalle JM, Jin LW Rett syndrome astrocytes are abnormal and spread MeCP2 deficiency through gap junctions. J Neurosci 29: 50515061. 11. Maezawa I, Jin LW Rett syndrome microglia damage dendrites and synapses by the elevated release of glutamate. J Neurosci 30: 53465356. 12. Okabe Y, Kusaga A, Takahashi T, Mitsumasu C, Murai Y, et al. Neural development of 
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