Type A fibril of the mouse tectorial membrane shows D-periodicity: an atomic force microscopic examination.

This study demonstrated that type A fibrils of the mouse tectorial membrane showed a morphology characteristic of collagen, as demonstrated using an atomic force microscope. In the topographical imaging mode, the surface of the type A fibrils showed a periodic pattern, consisting of alternating grooves and ridges. The periodicity of the type A fibrils was 69.1 +/- 0.6 nm, which is in accordance with characteristic collagen D-periodicity. The difference in height between grooves and ridges was 1.6 +/- 0.3 nm. In the variable deflection imaging mode, the type A fibrils showed a clear banding pattern, which consisted of alternating light and dark zones, with D-periodicity. In addition, the type A fibrils exhibited one minor dark band in the light zone and one minor light band in the dark zone.