Ammonium reduces CLS of <i>S. cerevisiae</i> through the regulation of both PKA and Sch9 activities.

<p>(A) Trehalase activity of wild-type (WT) N-starved cells and WT and mutant (<i>mep2Δ</i>, <i>sch9Δ</i> and <i>tor1Δ</i>) aa-starved cells, before transferred to water (T0h) and after 2 hours in water (T2h H₂O) or water with 0.5% (NH₄)₂SO₄ (T2h NH₄⁺). Survival of (B) wild-type aa-starved cells or (C) N-starved cells, after transfer to: (⧫) water (pH 7.0); (⋄) water with 0.5% (NH₄)₂SO₄ (pH 7.0); (▴) water (pH 7.0) supplemented with cAMP (4 mM); (▵) water with 0.5% (NH₄)₂SO₄ (pH 7.0) supplemented with cAMP (4 mM). Survival in water (pH 7.0) or water with 0.5% (NH₄)₂SO₄ (pH 7.0) of aa-starved cells of: (D) WT, <i>sch9Δ</i> and <i>hog1Δ</i>; (E) WT, <i>mep1Δ</i>, <i>mep2Δ</i> and <i>ras2Δ</i>; (F) WT, <i>tpkΔ</i> mutants (<i>tpk1Δ</i>, <i>tpk2Δ</i> or <i>tpk3Δ</i>). In all the cultures, starting cell density was about 3.8×10⁷ cells/ml and the initial pH was adjusted to 7.0. Values are means ± SEM (n = 3–4). (A) *<i>P</i><0.05 (WT H₂O <i>vs</i> WT 0.5% (NH₄)₂SO₄), (WT 0.5% (NH₄)₂SO₄<i>vs tor1Δ</i> 0.5% (NH₄)₂SO₄); **<i>P</i><0.01 (WT 0.5% (NH₄)₂SO₄<i>vs sch9Δ</i> 0.5% (NH₄)₂SO₄); (D) <i>P</i><0.05 (WT 0.5% (NH₄)₂SO₄<i>vs hog1Δ</i> 0.5% (NH₄)₂SO₄), <i>P</i><0.001 (WT H₂O <i>vs sch9Δ</i> H₂O); (E) <i>P</i><0.05 (WT 0.5% (NH₄)₂SO₄<i>vs ras2Δ</i> 0.5% (NH₄)₂SO₄); <i>P</i><0.01 (WT 0.5% (NH₄)₂SO₄<i>vs mep2Δ</i> 0.5% (NH₄)₂SO₄); <i>P</i><0.05 (WT 0.5% (NH₄)₂SO₄<i>vs mep1Δ</i> 0.5% (NH₄)₂SO₄); (F) <i>P</i><0.01 (WT 0.5% (NH₄)₂SO₄<i>vs tpk1Δ</i> 0.5% (NH₄)₂SO₄). Statistical analysis was performed by two-way ANOVA.