The nucleosomal repeat length of pea (Pisum sativum) chromatin changes during germination

Pea (Pisum sativum) nuclei have been isolated from ungerminated embryos, developing embryonic axes and seedlings. Morphological and biochemical criteria revealed that preparations were free from contaminants and that nuclei were intact. These circumstances permitted an accurate determination of nucleosomal repeat lengths, the values obtained being 175±4 base pairs for ungerminated embryos, 185±5 base pairs for 62-hours germinated embryonic axes and 185±3 base pairs for 6-day old seedlings. The results seem to indicate that the increase in repeat length is associated with the onset of transcription and/or replication of DNA.