title: P62 association with RNA is regulated by tyrosine phosphorylation.
abstract: The ras-GAP associated protein, p62, is a major tyrosine phosphoprotein in transformed and growth factor treated cells. Although its exact function is not known, it can bind directly to src-family tyrosine kinases and has been implicated as a linker protein bridging activated src family tyrosine kinases with downstream effectors. One novel feature of p62, revealed by its predicted amino acid sequence, is the presence of an RNA-binding region, the KH domain. As p62 becomes tyrosine phosphorylated when src-kinases become activated, we compared the RNA binding ability of p62 in both its phosphorylated and unphosphorylated state. The ability of p62 to bind RNA was severely impaired when p62 was tyrosine phosphorylated. This suggests that the ability of p62 to bind RNA is regulated by tyrosine phosphorylation and implicates the regulation of RNA as a component of tyrosine kinase signaling pathways.
authors.affiliation: Center for Immunology, Washington University School of Medicine, St. Louis, Missouri 63110.
authors.forename: L L
authors.initials: LL
authors.lastname: Wang
authors.forename: S
authors.initials: S
authors.lastname: Richard
authors.forename: A S
authors.initials: AS
authors.lastname: Shaw
mesh_terms: D001483:Base Sequence; D017931:DNA Primers / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000378:metabolism; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D010750:Phosphoproteins / Q000378:metabolism; D019000:Phosphotyrosine; D011485:Protein Binding; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051076:Proto-Oncogene Proteins c-fyn; D012313:RNA / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D011994:Recombinant Proteins; D015398:Signal Transduction; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000378:metabolism
chemical_list: D017931:DNA Primers; D004268:DNA-Binding Proteins; C074561:GAP-associated protein p62; D010750:Phosphoproteins; D011518:Proto-Oncogene Proteins; D016601:RNA-Binding Proteins; D011994:Recombinant Proteins; D019000:Phosphotyrosine; D014443:Tyrosine; D012313:RNA; D051076:Proto-Oncogene Proteins c-fyn