REDOX CONDITIONS SPECIFY THE PROTEINS SYNTHESIZED BY ISOLATED-CHLOROPLASTS AND MITOCHONDRIA

In chloroplasts and mitochondria isolated from pea leaves, S-35-methio nine incorporation reveals that different subsets of proteins are sele cted for synthesis in the presence of the external redox reagents ferr icyanide, ascorbate, duroquinol, dithiothreitol and dithionite, and in the presence of different electron transport inhibitors in the light (in chloroplasts) or with respiratory substrates (in mitochondria). Re dox state of specific electron carriers may therefore regulate express ion of specific genes in chloroplasts and mitochondria. The results ar e consistent,vith the hypothesis that chloroplast and mitochondrial ge nomes encode proteins whose synthesis must be regulated by electron tr ansport in photosynthesis and respiration.