Additional file 1: Fig. S1. Effect of high glucose treatment on IkBα expression over 60 min. Figure S2: DMSO, KT5720 and Inh. XII treatment does not significantly alter proteasome activity and composition under resting conditions. Figure S3: Silencing of CaMKIIα expression induces a drop of pRpt6(ser120)/Rpt6 ratio. Figure 4: DMSO, KT5720 and Inh. XII treatment does not modulate NF-kB signalling pathway under resting conditions. Figure S5: Generation of rMC1 clones expressing the Rpt6_S120A phosphodead mutant showing enhanced proteasome activity. Figure S6: Rpt6_S120A clones show constitutively elevate NF-kB activation. Figure S7: Determination of the dynamic linear range of actin and Ponceau.