Nucleic Acid Metabolism in Peanut Cotyledons

Peanutt seeds are a unique material for the study of nutcleic acid metabolism. At the onset of germinatioln RNA synthesis is initiated in the cotyledons an(l the content per cotyledon doubles by a week after plantinig (4, 9). Subsequently the RNA content rapidly declines with age of the plant (4). The in vivo degradation of RNA is matched by an increase in ribonuclease activity. Concomitant with this increase and decrease in net RNA content many enizymnes follow a similar developmental pattern (5). The peanut cotyledon therefore is a useful tissue to study nucleic acid and enzyme synthesis in the absence of cell division. Its cell population is primarily composed of large parenchyma cells whose major role is to supply the embryonic axes with nutrients during the early stage of germination. WVe therefore have selected the peanut seed to sttudy niucleic acid metabolism during seed germinationl and(l subsequent growth of the plant. In order to better tuinderstanid the chaniges in RNA and DNA whicl occulr (lurinig germiniationi this pl)per l)resenlts an atteml)t to study patternis of P32 labelinig of the nucleic aci(ds of l)eantit cotyledonis awl(i their partial characterizationi by chromatograplhy oni niiethylated albumin (MAK) colutmniis.