Component of ribonucleosomes, which are complexes of at least 20 other different heterogeneous nuclear ribonucleoproteins (hnRNP). hnRNP play an important role in processing of precursor mRNA in the nucleus. Identified in the spliceosome C complex. Identified in a IGF2BP1-dependent mRNP granule complex containing untranslated mRNAs. Interacts with GTPBP1. Localized in cytoplasmic mRNP granules containing untranslated mRNAs. The tyrosine phosphorylated form bound to RNA is found in microsomes (By similarity). Expression is low and neural-specific.