Purchase this article with an account.
H.-S. Kwon, T. V. Johnson, S. I. Tomarev; Myocilin Mediates Clustering of Nodal Components Along the Axolemma. Invest. Ophthalmol. Vis. Sci. 2010;51(13):1462.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Myocilin is expressed in ocular and non-ocular tissues. This study investigates possible functions of myocilin in the peripheral nervous system.
HEK293 cells were transiently transfected with cDNAs encoding gliomedin-Fc, neurofascin-Fc, FLAG-tagged full length human myocilin and/or its proteolytic fragments. Full length FLAG-tagged myocilin was purified from conditioned medium (CM) of transfected cells using FLAG-agarose and HiTrap-S chromatography. Interaction of myocilin with gliomedin and neurofascin-155 was studied by co-immunoprecipitation and immunohistochemistry. Adult mouse dorsal root ganglion (DRG) explants were cultured for 12 days on glass slides coated with poly-D-lysine and laminin and then treated for 30min with CM from cells expressing myocilin or with 12ug/ml of purified myocilin.
Myocilin interacted with gliomedin and neurofascin-155 as shown by their co-immunoprecipitation from CM of co-transfected cells. The olfactomedin domain of myocilin was critical for this interaction. Double immunolabeling using antibodies to gliomedin and myocilin revealed that myocilin was localized at the nodes of Ranvier in sciatic but not optic nerve. The levels of myocilin were increased at the nodes of transgenic mice expressing elevated levels of myocilin. Addition of myocilin-containing CM or purified myocilin induced the clustering of nodal components (neurofascin-155, ankyrinG) in DRG axons, similar to that observed after addition of gliomedin-containing CM.
Myocilin may serve as a ligand for neurofascin-155. Binding of myocilin to gliomedin and neurofascin may induce clustering of the nodal components in DRG axons and affect saltatory conduction.
This PDF is available to Subscribers Only