The hnRNP F protein: unique primary structure, nucleic acid-binding properties, and subcellular localization

摘要: More than 20 different heterogeneous nuclear ribonucleoproteins (hnRNPs) are associated with pre-mRNAs in the nucleus of mammalian cells and these proteins appear to influence pre-mRNA processing other aspects mRNA metabolism transport. The arrangement hnRNP on is likely be unique for each RNA may determined by RNA-binding preferences proteins. F (M(r) = 53 kD, pI 6.1) H 56 6.7-7.1) abundant components immunopurified complexes they have distinct nucleic acid binding properties. Unlike which display a varying range affinities ribonucleotidehomopolymers ssDNA, bind only poly(rG) vitro. were purified from HeLa affinity chromatography oligonucleotides derived peptide sequences used isolate cDNA encoding F. predicted amino sequence revealed novel protein three repeated domains related RNP consensus domain. Monoclonal antibodies produced against bacterially expressed specific both recognized divergent organisms, including yeast Saccharomyces cerevisiae. thus highly immunologically share identical peptides. Interestingly, immunofluorescence microscopy that concentrated discrete regions nucleoplasm, contrast general nucleoplasmic distribution previously characterized properties, intranuclear localization make them important RNAs containing guanosine-rich sequences.