Parkin also known as PRKN is a component of a multiprotein E3 ubiquitin ligase complex that mediates the targeting of substrate proteins for proteasomal degradation. Parkin plays a pivotal role in tagging proteins for degradation, a process essential for maintaining cellular homeostasis. Structurally, Parkin contains an N-terminal ubiquitin-like domain and several zinc-finger motifs, including RING (Really Interesting New Gene) domains, which are critical for its E3 ligase activity. These domains facilitate interactions with substrate proteins and the ubiquitin-conjugating machinery, enabling Parkin to regulate protein turnover effectively. The integrity of these structural motifs is vital for Parkin′s function, as mutations within these regions often disrupt its activity and are linked to autosomal recessive juvenile Parkinson′s disease.