Luciferase (LUC) heat denatured in the presence of recombinant Hsp30C (30C) and N-30C, but not C-30C, can be refolded in Xenopus oocytes. LUC (0.2 μM) was heat denatured alone (X) or with 6.0 μM of 30C (○), N-30C (□), or C-30C (▴) at 42°C for 15 minutes. Samples were microinjected into Xenopus oocytes, and LUC activity was determined over time as indicated in “Materials and Methods.” Data are representative of 3–5 trials and shown as the mean ± SE