A 40-year-old woman presents with muscle weakness, fatigue, and joint pain. Laboratory tests reveal elevated levels of antinuclear antibodies (ANA), and a diagnosis of systemic lupus erythematosus (SLE) is made. Her physician explains that SLE involves the formation of autoantibodies against nuclear antigens, including intrinsically disordered proteins (IDPs). Which of the following nuclear proteins is an example of an intrinsically disordered protein (IDP) often targeted by autoantibodies in systemic lupus erythematosus (SLE)?
