Plants encountered with drought and salinity produce osmolytes such as proline to help them overcome the stress. Proline is synthesized in a two-step pathway, in which ?1-proline-5-carboxylate synthase (P5CS) is the key enzyme. To produce cDNA from mRNA , total RNA was extracted from leaves of Arabidopsis thaliana exposed to saline conditions. cDNA first strand was made through application of oligo (dT) primer and amplification of P5CS mRNA was carried out by two specifics, primer and polymerase chain reaction. Application of labeled probe, confirmed the amplification.
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