Cullin-3 (Cul 3), is a protein that in humans is encoded by the CUL3 gene. Kipreos et al. (1996) identified a conserved gene family, designated cullin, with at least 5 members in nematodes, 6 in humans, and 3 in S. cerevisiae. Human CUL3 is an ortholog of nematode cul3. Hartz (2012) mapped the CUL3 gene to chromo -some 2q36.2 based on alignment of the CUL3 sequence with the genomic sequence (GRCh37). Sumara et al. (2007) found that KLHL9, KLHL13, and CUL3 in -teracted durectly in a 370-kD protein complex in HeLa cell lysates. Rondou et al. (2008) showed that interaction between KLH12 and the CUL3 ubiquitin ligase complex directed ubiquitination of dopamine receptor D4 (DRD4). KLH12 inter -acted directly with CUL3 and with the polymorphic intracellular loop-3 of D4. By immunoprecipitation cells expressing epitope-tagged proteins, Kigoshi et al. (2011) showed that KLHL7 interacted with CUL3 and ROC1 (RBX1).