Tissue‐specific and light‐dependent changes of chromatin organization in barley (Hordeum vulgare)

Abstract

The DNase I sensitivity of the nuclear genes encoding the NADPH‐protochlorophyllide oxidoreductase, the light‐harvesting chlorophyll a/b protein (LHCP), the hordeins and a 15‐kDa protein of unknown function was assayed in chromatin of etiolated and green leaves and endosperm tissue of barley (Hordeum vulgare L.). A tissue‐specific differentiation of chromatin structure was found for the LHCP, hordein and 15‐kDa protein genes. The genes for the LHCP and the 15‐kDa protein, which are expressed in leaf tissue, display DNase I sensitivity in leaves but not in endosperm. Hordein genes which are expressed solely in endosperm, were insensitive to low levels of digestion with DNase I in leaves but sensitive in endosperm. The effect of light on chromatin structure was determined by comparing leaves of etiolated plants and plants which had been grown under a day/night cycle. Only in the case of the 15‐kDa protein is there a remarkable change from a DNAse‐I‐sensitive configuration in etiolated leaves to a more resistant one in leaves from illuminated plants. The gene for the NADPH‐protochlorophyllide oxidoreductase was found to be equally sensitive to DNase I in leaves and endosperm. Copyright © 1986, Wiley Blackwell. All rights reserved