Knockdown of Ube3A, an E3 ligase, was found to reduce dendritic arborization in Drosophila neurons, and mutations of Ube3A are associated with Angelman Syndrome (AS), discussed in section “Protein Degradation and Disease” (Lu et al., 2009; Hamilton and Zito, 2013). The gene discussed is UBE3A; the disease is Angelman syndrome.