Figure 9.

Model of signaling pathways that mediate activity-dependent changes in dendritic complexity. Depolarization activates Rem2 signaling in at least two ways: (1) calcium entry through L-VGCCs triggers the transcription of Rem2, and (2) calcium activates CaMKII signaling. This Rem2/CaMKII signaling pathway negatively regulates dendritic complexity (Ghiretti et al., 2013 and this manuscript). Calcium entry through L-VGCCs also activates signal transduction pathway(s) that positively regulate dendritic complexity (“X”) in parallel to Rem2. Thus, the net effect on dendritic morphology is due to the combination of these signaling pathways. Note that a role for constitutively expressed Rem2 in mediating dendritic complexity is not excluded by our results.