Figure 7.

ER retention of Hsp150Δ in the absence of Sec13p function. The indicated yeast strains were preincubated for 15 min at 37°C and ³⁵S labeled for 5 min at 37°C. One sample was chased with CHX for 1 h at 37°C, and a parallel sample at 24°C, as indicated. The lysed cells (c; uneven-numbered lanes) and medium samples (m; even-numbered lanes) were subjected to immunoprecipitation with Hsp150 antiserum, followed by SDS-PAGE analysis. Strain numbers: a, H430; b, H440; c, H1107; d, H1545; e, H4; and f, H230. The cells expressed either Hsp150 or Hsp150Δ, or both, as indicated. On the left, molecular weight markers (kilodaltons), and on the right the ER forms and mature forms of Hsp150 and Hsp150Δ are indicated.