Figure 12.

Roles for RORα at different developmental stages of PCs. Based on temporally controlled knock-down experiments, the major roles of RORα at each PC developmental stage (Sotelo and Dusart, 2009) are shown. During the transition from the fusiform to stellate cell stages (P0–P4), RORα is required for the regression of primitive dendrites and terminal translocation of PCs to align in a single PL. During the transition from the stellate cell to young PC stage (P4–P8), RORα regulates the elimination of somatic dendrites and the maturation of single-stem dendrites. RORα is crucial for the dendritic branching, filopodia formation, and spine maturation that occur from these stages. After the PCs reach mature morphology, RORα is still required for the maintenance of dendrites and spines.