Gene and protein expression in the mp65Δ mutant. (A) Activation of the cell wall integrity. Activation of the cell wall integrity pathway was determined by Western blot analysis, as specified in the Methods section. The wild type (wt), mp65Δ mutant (hom) and revertant (rev) strains were grown in YEPD for 1.5 h at 28°C with or without Congo red (50 μg/ml). Protein extracts (150 μg) were loaded in each lane and analyzed with anti-p44/42 MAPK (panel 1), anti-MAPK (Panel 2), anti-Cek1p (Panel 3) and anti-Act1p (Panel 4) antibodies. (B) Cell wall damage response genes expression. Real-time PCR assays were conducted on RNA samples from wild type (wt), mp65Δ mutant (hom) and revertant (rev) strains. The reactions assayed the RNA levels of the MP65, DDR48, PHR1, STP4, CHT2 and SOD5 genes. The level of each RNA was normalized to the ACT1 RNA. The results are the means of 3 determinations. The bars indicate standard deviations.