Figure 6. Cu²⁺-induced KCTD1 fibrillar aggregates have enhanced resistance to proteolytic digestion.

KCTD1 (0.8 μg/μl) was incubated without (a) or with (b) 20 μM Cu²⁺ for 2 h at 37 °C, followed by digestion with 0–20 μg/ml proteinase K at 37 °C for 35 min. (c,d) as the same as (a,b) respectively, KCTD1 was replaced with bovine serum albumin (BSA). (e) Proteinase K was not detectable in the SDS–page gel at the concentrations used (0–20 μg/ml).