Functional characterization of the Sbh1p tm-domain mutants. A, Multicopy suppression of temperature-sensitivity of sbh1Δ sbh2Δ cells (H3232) by different mutant forms of SBH1 tm-domain. The sbh1Δ sbh2Δ cells were transformed with BIO-tagged SBH1 tm-domain mutants expressed from the ADH1 promoter in p426ADH and the growth of four independent transformants was monitored at 38 and 24°C. B, Lysates prepared from sbh1Δ cells (H3429) expressing BIO-tagged Sbh1p TM, mutants TM-1 to TM-7 or the empty vector were subjected to pull-down with streptavidin-coated magnetic beads. Beads and input samples were analyzed by Western blotting with anti-Sec61 antibodies or with HRP conjugated streptavidin to detect different versions of BIO-Sbh1p.