Msp1 is a conserved AAA ATPase in budding yeast localized to mitochondria where it prevents accumulation of mistargeted tail-anchored (TA) proteins, including the peroxisomal TA protein Pex15. Msp1 also resides on peroxisomes but it remains unknown how native TA proteins on mitochondria and peroxisomes evade Msp1 surveillance. We used live-cell quantitative cell microscopy tools and drug-inducible gene expression to dissect Msp1 function. We found that a small fraction of peroxisomal Pex15, exaggerated by overexpression, is turned over by Msp1. Kinetic measurements guided by theoretical modeling revealed that Pex15 molecules at mitochondria display age-independent Msp1 sensitivity. By contrast, Pex15 molecules at peroxisomes are rapidly converted from an initial Msp1-sensitive to an Msp1-resistant state. Lastly, we show that Pex15 interacts with the peroxisomal membrane protein Pex3, which shields Pex15 from Msp1-dependent turnover. In sum, our work argues that Msp1 selects its substrates on the basis of their solitary membrane existence.
Weir_2017_Dryad_README
README with descriptive information and instructions for use of this dataset. Also contains links to GitHub repositories containing Python and R analysis code.
Weir_fig_1c
Microscopy source images for Figure 1C. See Weir_2017_Dryad_README.md for additional information.
Weir_fig_2c_4d
Microscopy source images for Figures 2C and 4D. See Weir_2017_Dryad_README.md for additional information.
Weir_fig_3c_4f
Microscopy source images for Figures 3C and 4F. See Weir_2017_Dryad_README.md for additional information.
Weir_fig_3e
Microscopy source images for Figure 3E. See Weir_2017_Dryad_README.md for additional information.
Weir_fig_5c
Microscopy source images for Figure 5C. See Weir_2017_Dryad_README.md for additional information.
Weir_fig_6c
Microscopy source images for Figure 6C. See Weir_2017_Dryad_README.md for additional information.
Weir_fig_6e
Microscopy source images for Figure 6E. See Weir_2017_Dryad_README.md for additional information.
Weir_fig_7b
Microscopy source images for Figure 7B. See Weir_2017_Dryad_README.md for additional information.
Weir_fig_7c
Microscopy source images for Figure 7C. See Weir_2017_Dryad_README.md for additional information.
Weir_fig_7e
Microscopy source images for Figure 7E. See Weir_2017_Dryad_README.md for additional information.
Weir_fig_s1a_s1c
Microscopy source images for Figure 1-Figure Supplement 1A and 1C. See Weir_2017_Dryad_README.md for additional information.
Weir_fig_s6a
Microscopy source images for Figure 6-Figure Supplement 1A. See Weir_2017_Dryad_README.md for additional information.
Weir_fig_s6g_s6h
Microscopy source images for Figure 6-Figure Supplement 1G and 1H. See Weir_2017_Dryad_README.md for additional information.
Weir_fig_s6j_pex11
Microscopy source images for Figure 6-Figure Supplement 1J (Pex11 portion). See Weir_2017_Dryad_README.md for additional information.
Weir_fig_s6j_pex12
Microscopy source images for Figure 6-Figure Supplement 1J (Pex12 portion). See Weir_2017_Dryad_README.md for additional information.