A model of Kif7 and Sufu regulation of graded Gli activity in ventral cell fate specification.

<p>The concerted actions of Kif7 and Sufu alter the Gli activator to repressor ratio to regulate intracellular Gli activity for the specification of ventral cell fates (pMN, p3 and FP) from naïve neuroepithelial precursor cells. As Shh signaling increases Smo activity, Gli repressor formation and the inhibition of activators become less efficient as denoted (<b>i–iii</b>), while robust Smo activation results in Kif7 antagonizing the inhibition of Gli activators by Sufu for p3 and FP induction (<b>iv</b>).