Fig. 6. The double proline PrP mutant (dmPrP) accumulates in aggresomes of ALLN-treated cells. (A) CHO cells expressing P101L-PrP or the double mutant (P101L,P104L) dmPrP, as indicated, were treated either with 30 µg/ml CsA or 15 µM ALLN for 48 h or left untreated and examined by confocal immunofluorescence microscopy using RO73 (green). In untreated cells as well as in cells treated with CsA, both mutants behaved similarly to the wtPrP. In contrast, in ALLN-treated cells, the distribution of the mutants differed significantly from that of wtPrP as: (i) P101L-PrP formed diffuse perinuclear deposits (lower panel), which could sometimes be seen by Nomarski optics as well (upper panel); (ii) in a few cells, dmPrP formed tight juxtanuclear foci, and because these deposits were surrounded by a vimentin cage (B), we identified them as aggresomes.