Figure 37.3 -Figure 37.3 Is a Northern Blot Showing the Expression of Expression

Figure 37.3
-Figure 37.3 is a Northern blot showing the expression of Myb mRNA in cultured aleurone layer cells that were treated with gibberellin versus control cells that were not treated with gibberellin. Only the gibberellin- treated cells expressed the Myb mRNA, but the Myb mRNA was not detectable until 6- 12 hours after gibberellin application. Why did it take so long?

A) Gibberellin had to enter the cells and find the Myb gene among the large plant genome.
B) Gibberellin had to bind to a receptor and initiate a signal transduction cascade that, in turn, had to activate a transcription factor that triggered the transcription of the Myb gene.
C) Gibberellin had to diffuse into the aleurone layer cells and be metabolized in order to trigger activation of a transcription factor that triggered transcription of the Myb gene.