GOLIM4 and cancer: To determine whether GOLIM4 functions as a Mn-binding protein in 3q-amplified cancer cells, we passed cell lysates over a Mn-binding resin and conducted LC-MS analysis on the eluted proteins, which identified a total of 10 proteins, including GOLIM4, the only Golgi-resident protein with detectable Mn-binding activity (Supplemental Figure 8, A and B).