Figure 8.

Gene expression of the mitotic cyclin cycB2;2 in adventitious roots at the third node as determined with RT-PCR. A, Gene expression in three consecutive tissue sections 2 mm in width as measured in plants submerged for the times indicated. This control experiment showed that significant cycB2;2 expression and induction was limited to the tissue section containing the roots. The time course of transcript accumulation was comparable to that found using northern-blot analysis (Figs. 3 and 4). B, Gene expression in the middle, root-containing tissue as a result of treatment for 12 h with ethephon, IAA, or NBD in combination with ethephon or IAA at the concentrations indicated. As a control (c), PCR was performed using the plasmid containing the cycB2;2 cDNA as a template source.