HNRNP-G - SEQUENCE AND CHARACTERIZATION OF A GLYCOSYLATED RNA-BINDINGPROTEIN

The autoantigen p43 is a nuclear protein initially identified with aut oantibodies from dogs with a lupus-like syndrome. Here we show that p4 3 is an RNA-binding protein, and identify it as hnRNP G, a previously described component of heterogeneous nuclear ribonucleoprotein complex es. We demonstrate that p43/hnRNP G is glycosylated, and identify the modification as O-linked N-acetylglucosamine. A full-length cDNA clone for hnRNP G has been isolated and sequenced, and the predicted amino acid sequence for hnRNP G shows that it contains one RNP-consensus RNA binding domain (RBD) at the amino terminus and a carboxyl domain rich in serines, arginines and glycines. The RBD of human hnRNP G shows st riking similarities with the RBDs of several plant RNA-binding protein s.