Relationship Between Red Light Mediated Glyceraldehyde-3-Phosphate Dehydrogenase Formation and Light Dependent Development of Photosynthesis

Abstract

In-crease in Phaseolus vulgaris leaf glyceraldehyde-3-phosphate dehydrogenase can occur in the absence of chlorophyll synthesis. This response is mediated by phytochrome. Other phytochrome-mediated responses, increase in leaf area, and ability of leaves to synthesize chlorophyll were also activated. These phytochrome-mediated responses were brought about either by extended exposure to far-red light or repeated short exposures to red. However, exposure to far-red light did not overcome the inhibitory effect of chloramphenicol, during subsequent white light irradiation, on development of photosynthesis. This suggested that formation of the enzymes whose synthesis is light-dependent and chloram-phenicol-sensitive requires light other than that needed to convert the red-absorbing form of phytochrome to its far-red form.