first type I K homology (KH) RNA-binding domain found in fragile X mental retardation protein 1 (FMR1) and similar proteins
FMR1, also called FMRP, or synaptic functional regulator FMR1, is a multifunctional polyribosome-associated RNA-binding protein that plays a central role in neuronal development and synaptic plasticity through the regulation of alternative mRNA splicing, mRNA stability, mRNA dendritic transport and postsynaptic local protein synthesis of a subset of mRNAs. It also plays a role in the alternative splicing of its own mRNA. FMR1 contains three K-homology (KH) RNA-binding domains. The model corresponds to the first one. Members in this subfamily contain a divergent KH domain that lacks the RNA-binding GXXG motif.