Figure 8. Model of Dicer1 and miR-219 promotion of OL differentiation.
Arrows indicate a promotion of pathway or expression, and bars indicate inhibition of pathway or expression. Stronger activity/expression is denoted by bold lines/text, and weaker activity/expression is denoted by grey lines/text. A. OL differentiation is inhibited by several OPC-expressed genes in the presence of large amounts of PDGF/early development under normal conditions. B. When mitogens become limiting, Dicer1 and miR-219 expression is induced, leading to a direct, accelerated repression of several OPC-expressed genes and a de-repression of OL differentiation. See text for additional details.