Intermittent-light chloroplasts are not developmentally equivalent to chlorina f2 chloroplasts in barley

Both the chlorina f2 mutant of barley and plants grown under intermittent light have fully functional photosystems but completely lack Chl b. These two systems were compared for the presence or absence of Chl a+b-binding polypeptides using snsitive immunoblotting techniques. Both types of plants contained the apoprotein of CP29 and the minor 25 kD polypetide of LHCII, and were severely depleted in the major LHCII polypeptides. However, intermittent light plants were completely lacking LHCI polypeptides, in contrast to chlorina f2 which has at least some of them (White and Green 1987b). None of the polypeptides could be detected in dark-grown plants. This shows that intermittent light plants are not physiologically or developmentally equivalent to chlorina f2 plants. Different factors appear to be involved in controlling the synthesis/accumulation of the polypeptides of the three complexes.