Figure 2. CrMPK3 provides tolerance to yeast against abiotic stresses. CrMPK3 was cloned in vector pYES2.1. BCY123 yeast cells were transformed either with pYES 2.1:CrMPK3 or vector alone (pYES2.1). The transformed overnight grown yeast cultures were diluted to OD600 = 0.5 in 2% Gal, 50 mM MES pH 5.5 and subjected to different stress treatments. 10 μl of original culture (OD600 = 0.5), along with different serial dilutions (10⁻¹, 10⁻², 10⁻³ and 10⁻⁴ cells), were spotted on dropout media lacking Uracil and containing 2% Galactose as inducer. (A) Heat shock was given by incubating yeast cultures in a water bath maintained at a temperature of 45°C for 30 min. (B) UV exposure by exposing the cultures to UV-C light for 45 min; (C) cold shock was given by incubating the cultures at 4°C for 1 h. The experiments were repeated three times with similar results. (D) Activation of MAP kinase by heat treatment in C. roseus leaves. C. roseus plants were subjected to heat stress and leaves were harvested at indicated time intervals post-treatment. Protein extract (20 μg) from these samples were tested for kinase in in-gel kinase assay using Mylein Basic Protein (MBP) as artificial substrate polymerized in SDS 10% (w/v) polyacrylamide gel. Autoradiogram represents in-gel phosphorylation of MBP.