Structural changes of human RNase L upon homodimerization investigated by Raman spectroscopy

► Structural response of binding of different pA3X, including natural one, is uniform. ► Homodimer formation increases β-sheet and decreases α-helical content. ► α-β structural switch probably fixes domain positions during the homodimer formation. ► At least 3 Tyr, 5 Phe and 2 Trp participate in homodimer formation upon 2-5A binding.