CUL7 (cullin 7) is a core component of two distinct E3 ubiquitin ligase complexes: the 3M complex and the Cul7-RING(FBXW8) complex, both involved in protein ubiquitination and degradation pathways 1. The protein functions as a molecular scaffold that positions substrates near RING-bound E2 ubiquitin-conjugating enzymes to facilitate ubiquitin transfer 1. CUL7-containing complexes target various proteins for degradation, including IRS1 in insulin signaling, ATGL in lipolysis regulation, and TET2 in cancer drug resistance 234. The 3M complex regulates microtubule dynamics and genome integrity, though the precise mechanism remains unclear 1. Disease associations include 3M syndrome 1, caused by CUL7 mutations leading to growth defects 5. In cancer, CUL7 expression is often upregulated and associated with poor prognosis in colon adenocarcinoma 6. Additionally, CUL7 contributes to photoreceptor ferroptosis in retinal degeneration by promoting GPX4 ubiquitination and degradation 7. The gene shows potential involvement in autism spectrum disorders through inherited truncating mutations 8, highlighting its broad physiological importance in development, metabolism, and disease pathogenesis.