Figure 2: DJ-1 physically binds to the 20S proteasome.
From: The Parkinson’s-associated protein DJ-1 regulates the 20S proteasome
Free 20S proteasomes (a), 20S proteasomes mixed with DJ-1 (b) and free DJ-1 (c) were examined by native MS. For each sample, the most intense charge state obtained in the MS spectrum was subjected to MS/MS analysis (inset shows the MS spectrum of the free 20S proteasome; the 58+ charge state highlighted in red was subjected to MS/MS analysis). Comparison of the free 20S spectrum (a), with that recorded for 20S in the presence of DJ-1 (b), revealed additional peaks that correspond in mass to the monomeric form of DJ-1, as seen in (c). By extrapolation, we can therefore conclude that before MS/MS analysis, DJ-1 binds to the 20S proteasome. Blue and cyan dots correspond to two different α subunits of the 20S proteasome; yellow dots represent monomers of DJ-1.
