TABLE 4.

Altered homeostatic plasticity in Rett syndrome and Fragile X syndrome.

Source	Region/Sample	Experiment	Findings	References
Mecp2–/y by shRNA	Hippocampus	Whole cell voltage clamp	Mecp2 downregulation prevents activity-dependent synaptic scaling	Qiu et al., 2012
Mecp2 knockdown by shRNA	Rat visual cortex neurons	Whole cell patch clamp	MeCP2 is necessary for cell-autonomous scaling up	Blackman et al., 2012
Mecp2 tm1.1Jae	Hippocampal neurons	Whole cell patch clamp and molecular analysis	↑ EEA1 expression re-establishes synaptic scaling in Mecp2 mutant mice	Xu and Pozzo-Miller, 2017
Mecp2S421A; S424A/y and Mecp2–/y	Hippocampal neurons	Whole cell patch clamp and molecular analysis	MeCP2 phosphorylation is necessary for synaptic scaling	Zhong et al., 2012
Fmr1–/Y	Hippocampal slice/cultures	Patch Clamp	FMRP is necessary postsynaptically to mediate the RA mediated synaptic scaling	Soden and Chen, 2010
Fmr1–/Y	Hippocampal neurons	Patch Clamp	GluA1 ubiquitination synaptic downscaling is prevented in Fmr1 knockout mice	Lee et al., 2018

Main findings of studies reporting homeostatic plasticity in Rett syndrome and Fragile X syndrome. Mecp2, methyl-CpG binding protein 2 gene; Fmr1, fragile X mental retardation 1 gene, FRMP, fragile X mental retardation protein EEA1, early endosome antigen 1, RA, retinoic acid.