[On the supramolecular structure of eye lens crystalline. A study by small-angle x-ray scattering]

The supramolecular structure of clystallins from bovine and frog eye lens tissues was studied by small-angle X-ray scattering. The measurements were carried out at different orientations of the lens tissue on a diffractometer equipped with a coordinate detector with point collimation of the X-ray beam. The results indicate that crystallins occur in the lens in different structural states. One state is characterized by a small-angle diffraction maximum in the range of Bragg's distances D-15-22 nm, which is explained by a near order of macromolecular complexes of crystallins (alpha-crystallin), whereas for the other state, small-angle diffraction maxima in the range D-15-22 nm are not observed. The assumption is made that the second state is related to a homogeneous distribution of crystallin polypeptides in the lens and that the transition from this state to the state with the near order of macromolecular complexes may be due to the chaperone activity of these proteins.