Binds single-stranded RNA. Has a high affinity for G-rich and U-rich regions of hnRNA. Also binds to APOB mRNA transcripts around the RNA editing site. Identified in a IGF2BP1-dependent mRNP granule complex containing untranslated mRNAs. Interacts with APOBEC1. Localized in cytoplasmic mRNP granules containing untranslated mRNAs. Ubiquitous. Dimethylation at Arg-322 is probably asymmetric.