Figure 2.
Expression of different RAS gene constructs in a ras2 mutant strain. (A) Shown is invasive growth of yeast strain YHUM86 (ras2) containing YCplac22 (vector), YCplac22-RAS2 (RAS2), YCplac22-RAS2Val19 (RAS2V19), YEplac112-RAS2 (2 μm RAS2), pRS314-RAS2ΔC (RAS2ΔC), pRS314-R2N-R1C (R2N-R1C), YEplac112-RAS1 (RAS1 2 μm) or YCplac22-R2p-R1orf (R2p-R1orf). Plates were incubated for 4 d and photographed before (Total growth) and after (Invasive growth) washing cells of the agar surface. (B) Expression levels of Ras proteins was determined in strains described in A by Western blot analysis using monoclonal anti-H-Ras antibody (259) that cross-reacts equally well with either Ras1p or Ras2p (upper panel, short exposure; lower panel, long exposure). (C) Autoradiogram showing steady-state levels of RAS1 and RAS2 mRNA in strains described in A. ACT1 gene expression was used as internal standard. (D) FG(Ty1)::lacZ expression levels. β-Galactosidase activity was measured on strains described in A. Units are nanomoles per minute per milligram. Bars depict means of three independent measurements. White bars indicate RAS2-independent expression of FG(Ty1)::lacZ.