Acceleration of brain tubulin formation in the optic lobe of the chick embryo by light stimulation.

The effect of light exposure on the protein patterns of optic lobe and forebrain of the chick embryo was analysed by a high-resolution micro-two-dimensional polyacrylamide gel electrophoresis and computerized quantitation. Experiments were done on three groups of eggs: control group was incubated in the dark; simultaneously, in the same incubator, one group of eggs was illuminated by constant light, another by intermittent light (3 sec interval) from day 10 to day 16 of incubation. In embryos exposed to intermittent light the relative amount of tubulins was significantly increased in the optic lobe. In the frontal lobe no effect of light exposure on the concentration of tubulins was seen. The rise of tubulins in the optic lobe was only caused by intermittent light. Continuous illumination of the eggs for the same period under otherwise identical incubation conditions was ineffective.