Figure 6.

Association of Pex5p with organelle membranes. (A) Pex5p accumulates on organelles of aging HDFs. Pex5p was immunoprecipitated from detergent-solubilized organelles of early-passage (E), middle-passage (M), or late-passage (L) IMR90 HDFs using anti-Pex5p antisera (α5) or preimmune sera (PI), as indicated, and immunoblotted with anti-Pex5p antisera. Organellar PMP70 was also examined by immunoblotting. The graph represents quantification of the α5 immunoblot with a Fujifilm LAS100plus luminescent image analyzer. The units on the ordinate are arbitrary. Equivalent results were obtained in three different experiments. (B) Pex5p accumulates on the outside of organelles from late-passage cells. Organelles from late-passage IMR90 HDFs were treated with proteinase K and Triton X-100 or untreated, as indicated, and the resultant organelles were immunoblotted with anti-Pex5p or anti-catalase antisera.