Abstract: The invention concerns a novel 116 kDa polypeptide exhibiting homologies of sequences with RNA helicases (DEXH box) called RH116 and its fragments, the cloning of cDNA and the polynucleotides encoding said polypeptides, cloning and/or expression vectors including said polynucleotides, cells transformed by said vectors and specific antibodies directed against said polypeptides. The invention also concerns methods for detecting and/or assaying said polypeptides and polynucleotides, corresponding diagnosis kits, and a method for screening ligands, as well as compounds for use as medicine for preventing and/or therapeutic treatment.

Abstract: The invention concerns a novel SSA-56 kDA polypeptide and its fragments, cDNA cloning and polynucleotides encoding said polypeptides, cloning and/or expression vectors including said polynucleotides, cells transformed by said vectors and specific antibodies directed against said polypeptides. The invention also concerns methods for detecting and/or assaying said polypeptides and polynucleotides, corresponding diagnostic kits, a method for screening ligands, a method for detecting anti-Ro/SSA-like autoantibodies, a method for purifying a human biological fluid capable of containing anti-Ro/SSA-like autoantibodies, and compounds for use as medicines for preventing and/or treating viral pathologies such as AIDS and autoimmune diseases, in particular systemic lupus erythematosus (SLE)and Sjögren syndrome.