Synthesis of DNA and of Hydrolytic Enzymes in Cotyledons of Germinating Seeds of Agrostemma githago L.1)1)Herrn Prof. Dr. H. Borriss zum 70. Geburtstag in Verehrung gewidmet.
1979; Elsevier BV; Volume: 174; Issue: 7 Linguagem: Inglês
10.1016/s0015-3796(17)30606-6
ISSN0015-3796
AutoresMichael Hecker, D. Bernhardt, K.‐H. Köhler, B. Schmerder, H. Dunger, R. Knösche,
Tópico(s)Plant Molecular Biology Research
ResumoIn imbibing seeds of Agrostemma githago DNA is synthesized firstly in the root tips of the embryos even before the radicle protrudes, whereas the incorporation of [3H]-thymidine remains on a low level in the cotyledons. Only after germination a drastic enhancement of [3H]-thymidine incorporation starts also in the cotyledons. This incorporation is due to a nuclear DNA synthesis. In about 70% of the cell nuclei the DNA content is doubled during a germination period of 120 h, i. e. it is raised from 2 C to 4 C, whereas the doubling starts after 24 h which is hardly followed by cell divisions. After beginning of DNA synthesis in the cotyledons the formation of hydrolytic enzymes (acid phosphatase, α-amylase and invertase) turns on as deduced from increasing enzyme activities. Several experiments with specific inhibitors suggest a correlation between DNA synthesis and formation of hydrolytic enzymes. We suggest that DNA synthesis in cotyledons is a prerequisite for the formation of hydrolytic enzymes.
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