In 2018, several C-terminal degradation signals were identified in human proteins, which can be recognized by the CRL E3 ligases as well as other E3s (Fig. 4) [62,63]. The Gly/C-degron was recognized by the Kelch-repeat domain-containing component of the CRL2 complexes, such as KLHDC2 [64], KLHDC3 [65], and KLHDC10 [66], and each recognin recognizes a distinct sequence motif. KLHDC2 prefers the C-end motif of -GG, KLHDC3 recognizes the −R/KG C-end motif and KLHDC10 targets the −A/W/PG C-end