Rn. Etingof et Nd. Shushakova, MEMBRANES OF RETINAL MICROSOMES - A NEW-P ROTEIN OF THE MICROSOMAL MONOOXYGENASE SYSTEM, Biologiceskie membrany, 14(2), 1997, pp. 143-152
A new component, which substitutes cytochrome P-450 as an acceptor of
reducing equivalents from NADPH-cytochrome P-450 reductase, was identi
fied in bovine retina microsomal monooxigenase system, which does not
contain cytochrome P-450. This component is a non-heme iron-containing
protein with molecular mass of 66 kDa. The properties of the protein
from bovine retina are similar to those of MIP, a non-heme iron-contai
ning protein from heart microsomal monooxigenase system, in which cyto
chrome P-450 also was not identified, The microsomal monooxigenase sys
tem activation (increase in the NADPH-cytochrome P-450 reductase activ
ity, an increased rate of microsomal NADPH oxidation) was shown in the
retina upon long-term intensive illumination. It was found also that
the development of hereditary degeneration of the retina in rats is ac
companied by specific microsomal monooxigenase system activation in th
e target tissues (retina, brain cortex) irrespectively of its composit
ion (cytochrome P-450 or non-heme iron-containing protein).