This domain family is found in eukaryotes, and is typically between 126 and 160 amino acids in length. The family is found in association with Pfam:PF05641, Pfam:PF00013. This family is the core C terminal region of the fragile X related 1 proteins FXR1P, FXR2 and FMR1. These different proteins have different regions at their very C-terminus. The Glutamine-arginine rich region facilitates protein interactions [3]. This family contains two blocks of RGG repeats that bind to G-quartet sequences in a wide variety of mRNAs [2].

1: The RNA-binding protein fragile X-related 1 regulates somite formation in Xenopus laevis. Huot ME, Bisson N, Davidovic L, Mazroui R, Labelle Y, Moss T, Khandjian EW; Mol Biol Cell. 2005;16:4350-4361. PMID:16000371

2: mRNPs, polysomes or granules: FMRP in neuronal protein synthesis. Zalfa F, Achsel T, Bagni C; Curr Opin Neurobiol. 2006;16:265-269. PMID:16707258

3: Short- and long-term memory are modulated by multiple isoforms of the fragile X mental retardation protein. Banerjee P, Schoenfeld BP, Bell AJ, Choi CH, Bradley MP, Hinchey P, Kollaros M, Park JH, McBride SM, Dockendorff TC; J Neurosci. 2010;30:6782-6792. PMID:20463240