 However, hnRNPs also have their own nuclear localization sequences (NLS) and are therefore found mainly in the nucleus.Though it is known that a few hnRNPs shuttle between the cytoplasm and nucleus, immunofluorescence microscopy with hnRNP-specific antibodies shows nucleoplasmic localization of these proteins with little staining in the nucleolus or cytoplasm.This is likely because of its major role in binding to newly transcribed RNAs.