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RNA and microRNAs in fragile X mental retardation

Abstract

Fragile X syndrome is caused by the loss of an RNA-binding protein called FMRP (for fragile X mental retardation protein). FMRP seems to influence synaptic plasticity through its role in mRNA transport and translational regulation. Recent advances include the identification of mRNA ligands, FMRP-mediated mRNA transport and the neuronal consequence of FMRP deficiency. FMRP was also recently linked to the microRNA pathway. These advances provide mechanistic insight into this disorder, and into learning and memory in general.

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Figure 1: Model of fragile X mental retardation protein (FMRP) function in the neuron.
Figure 2: Model for RNAi-mediated methylation of expanded CGG repeats in individuals with fragile X syndrome.

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Acknowledgements

We would like to thank the members of the Warren and Jin laboratories for input, and J. Clark, C. Gilman and K. Garber for assistance. We were supported, in part, by grants from the Rett Syndrome Research Foundation (P.J.), the FRAXA Research Foundation (R.S.A.) and National Institute of Health (S.T.W).

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Correspondence to Stephen T. Warren.

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Jin, P., Alisch, R. & Warren, S. RNA and microRNAs in fragile X mental retardation. Nat Cell Biol 6, 1048–1053 (2004). https://doi.org/10.1038/ncb1104-1048

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