Gibberellic acid breaks dormancy of hazel seeds. Markedly preceding growth of the embryonic axis is an increased RNA synthesis, as shown by total RNA determination and32P incorporation into RNA. This increased RNA synthesis is accounted for by an increase in DNA template available for transcription and (subsequently) increased RNA polymerase activity. It is suggested that gibberellic acid breaks dormancy by a mechanism of gene derepression, as indicated by increased chromatin-directed RNA synthesis as measured in vitro.
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