It has been suggested that some retinal degenerations are the result of malfunction of the connecting cilium of the photoreceptor cell. We have reported the case history of an individual with retinal degeneration in whom the acetylation of stable microtubules is greatly reduced. We are at present studying the characteristics of the acetylation activity associated with stable microtubules from bovine tissues to identify likely candidates responsible for such pathologies. Preliminary results suggest that movement of material along microtubules is associated with the acetylating activity which exists in a macromolecular complex. This complex from retina contains at least two photoreceptor-specific proteins which move from the inner to the outer segment in response to light, the reduction or absence of which would be expected to comprise photoreceptor cell integrity.
Lloyd, R.A., S. Gentleman and G.J. Chader "Assay of tubulin acetyltransferase activity in subcellular tissue fractions." Anal. Biochem. 216,42-46 (1994).
Gentleman, S., et al. "Ultrastructural and biochemical analysis of sperm flagella from an infertile male with a rod-dominant retinal degeneration." Human Pathol. (in press). Document date: 29 November 1995