A Model of MicroRNA–Mediated Repression of Seed Genes in Leaves.

<p>In wild type seedlings, AGO1 and miR166 repress the expression of <i>PHB</i>/<i>PHV</i>, which promotes the seed maturation program by directly activating <i>LEC2</i> expression and indirectly that of other positive regulators of the seed maturation program. miR156 may also play a role in the process, possibly by repressing <i>SPL10</i> and <i>SPL11</i>, based on this work and that of Nodine and Bartel <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1003091#pgen.1003091-Nodine1" target="_blank">[53]</a>. It is not known, however, whether SPLs are sufficient for inducing the expression of seed genes or whether they directly activate the seed genes.