Reconstitution of a light-stimulated adenylate cyclase from retina and Neurospora crassa preparations. Characterization of the heterologous systems using normal and degenerative retinas

MUSCHIETTI, J.P.; BIANCHINI, G.M.; MARTINETTO, H.E. ; CARRICARTE, V.C.; GIUSTO, N.M.

EUROPEAN JOURNAL OF BIOCHEMISTRY

FEBS

Año: 1989 vol. 185 p. 205 - 210

0014-2956

Adenylate cyclase catalytic subunits from Neurospora crassa membranes may interact with regulatory factors from membranes of bovine retinal rod outer segments (pretreated with N-ethylmaleimide), reconstituting a heterologous system which, in the presence of light, is catalytically active in assay mixtures containing MgATP. Maximal activation was observed at 550 nm. Transducin-depleted retinal membranes were not capable of reconstituting the heterologous light-stimulated adenylate cyclase system. Addition of a transducin preparation to depleted membrancs restored the reconstitution capacity of these membranes. A similar heterologous adenylate cyclase system was reconstituted with Neurospora and mouse retinal whole membranes (pretreated with N-ethylmaleimide). Membranes from mice suffering photoreceptor degeneration (rd homozygotes) did not reconstitute an heterologous adenylate cyclase system.