Accuracy modulating mutations of the ribosomal protein S4-S5 interface do not necessarily destabilize the rps4-rps5 protein–protein interaction

Analysis of interactions between rpS4 and rpS5 and mutants by coimmunoprecipitation assays. Extracts containing 40 μg of protein were incubated with anti HA agarose slurry (6 μL) overnight at 4°C washed and eluted in 25 μL of nonreducing sample buffer. Equal amounts (10 μL) of washed and eluted samples were loaded in duplicate and detected by anti-LexA (above) or anti-HA antibody (below). Transformants with pB42AD-S4 cotransformed with pGilda vector is shown as a negative control. G101D was expressed at equivalent levels to the wild-type protein (data not shown).