Light-induced down-regulation of the rat class 1 dynein-associated proteinrobl/LC7-like gene in visual cortex

Dynein and kinesin are the main microtubule-dependent motors that mediate i ntracellular movement in eukaryotic organisms. We have cloned a full-length cDNA encoding rat dynein light chain protein, robl/LC7-like (class 1), fro m visual cortex. We found that rat robl/LC7-like gene is highly expressed i n neocortex and displays the unusual feature of being rapidly down-regulate d by sensory stimulation. This effect was seen at both mRNA and protein lev els in visual cortex, being detectable in as little as 45 min after the ons et of visual stimulation. Down-regulation by sensory stimulation was also f ound within ocular dominance columns of area V1 in monocularly deprived mon keys. Our results suggest a high turnover rate of the robl/LC7-like protein and the presence of a repressor mechanism in neurons that is tightly coupl ed to synaptic stimulation.