PT - JOURNAL ARTICLE AU - Xu, Xia-Lian AU - Zong, Ruiting AU - Li, Zhaodong AU - Biswas, Md Helal Uddin AU - Fang, Zhe AU - Nelson, David L. AU - Gao, Fen-Biao TI - FXR1P But Not FMRP Regulates the Levels of Mammalian Brain-Specific microRNA-9 and microRNA-124 AID - 10.1523/JNEUROSCI.2827-11.2011 DP - 2011 Sep 28 TA - The Journal of Neuroscience PG - 13705--13709 VI - 31 IP - 39 4099 - http://www.jneurosci.org/content/31/39/13705.short 4100 - http://www.jneurosci.org/content/31/39/13705.full SO - J. Neurosci.2011 Sep 28; 31 AB - Mammalian brain-specific miR-9 and miR-124 have been implicated in several aspects of neuronal development and function. However, it is not known how their expression levels are regulated in vivo. We found that the levels of miR-9 and miR-124 are regulated by FXR1P but not by the loss of FXR2P or FMRP in vivo, a mouse model of fragile X syndrome. Surprisingly, the levels of miR-9 and miR-124 are elevated in fmr1/fxr2 double-knock-out mice, in part reflecting posttranscriptional upregulation of FXR1P. Indeed, FXR1P is required for efficient processing of pre-miR-9 and pre-miR-124 in vitro and forms a complex with Dicer and pre-miRNAs. These findings reveal differential roles of FMRP family proteins in controlling the expression levels of brain-specific miRNAs.