Abstract:
The incorporation of the methyl group from S-methyl-Lmethionine-14CH3 into the nucleic acid, DNA, in germinating winter wheat seedlings was investigated during the early germination period of 4 days.Counts per minute per gram of tissue in the root was highest on day 1 and dropped rapidly until day 3, followed by a slight rise. In the shoot, the counts per minute per gram of tissue was also highest on day 1, dropping rapidly to its lowest point on day 4. There was no fluctuation in the counts per minute per gram of tissue in the remaining seed parts, which remained at a lower level than the other two groups.Since any protein, which may have contained S-methyl-Lmethionine or its dissociated methyl group, was "salted out" using saline-EDTA, and the procedure used was for DNA isolation, the results indicate that the methyl group was incorporated into the DNA of the root and shoot of the germinating wheat seedlings. The decrease in counts per minute per gram of tissue for the root and shoot was expected as a result of the labeled DNA being replicated and dispersed throughout the rapidly growing root and shoot, after an initial incorporation of the labeled methyl group.
