Changes in Nucleic-Acid Metabolism in Regreening leaves of Perilla

Regreening of senescent leaves of Perilla occurs after removalof all aerial parts of the plant except for one pair of leaves.After 3 weeks' regreening, chlorophyll had increased twofoldand RNA fourfold, compared with amounts present in the matureleaf. Polyacrylamide-gel electrophoresis of the rRNAs showedthat although at the time of decapitation chloroplast-rRNA synthesishad ceased, this was resumed by 12 h following decapitation.The results are discussed in relation to current knowledge ofthe control of ribosome metabolism.