UBE3A: Bridging the gap between neurodevelopment, neural function, and neurodegenerative woes.

Post-translational modifications (PTMs) of proteins play a significant role in normal protein function but can also be instrumental in disease pathogenesis. One critical yet under-studied PTM in disease is ubiquitination. Ubiquitin chain addition and substrate specificity are determined by a large spectrum of ubiquitin-ligating and -modifying enzymes, E3 ligases, whose expression levels and activities are tightly regulated in a cell-specific manner. While most ubiquitin chains can target proteins for proteasomal degradation, ubiquitination can contribute to other functions within the cell, including protein localization, protein activity, endocytosis, transcription, and autophagy. One E3 ligase, UBE3A, has garnered much attention because of its involvement in learning and memory, as well as its association with neurodevelopmental autism spectrum disorders (ASDs). However, more recent findings have suggested a potential involvement of UBE3A in neurodegenerative proteinopathies, where reduced UBE3A levels can lead to an enhanced rate of aggregate formation and cell death. Here, we review the literature on UBE3A in neurodevelopment, function, and neurodegenerative diseases and demonstrate that UBE3A could play a critical role in disease progression and cognitive function.