LIGHT-ENHANCED GENE-EXPRESSION OF NADPH-PROTOCHLOROPHYLLIDE OXIDOREDUCTASE IN CUCUMBER

The NADPH-protochlorophyllide oxidoreductase (NPR) is a well known enz yme catalyzing photoconversion of protochlorophyllide to chlorophyllid e a and its expression is negatively regulated by light. We cloned a N PR cDNA from cucumber (Cucumis safivus L.). The cDNA contained an open reading frame encoding 398 amino acids and amino acid sequence showed high similarity to those of NPR from other plants. Contrasting with m ost other plants, the levels of the NPR mRNA increased in etiolated co tyledons of cucumber when they were illuminated with continuous light, suggesting that the expression of this NPR gene was strongly related to chlorophyll synthesis in green leaves. (C) 1995 Academic Press, Inc .