Cloning and Characterization of and Genes from P 5 CS 1 P 5 CS 2 Saccharum officinarum L . under Drought Stress

Increasing world sugar demand might be ful lled with extensi cati n which include the use of land o dry area. Development of drought tolerance and high productivity sugarcane could be by variety achieved plant genetic engineering. Under drought condition, proline will be accumulated and functioned as an osmoregulator in plant. Δ -5-pyrroline carboxylate synthase (P5CS) is one of the important enzyme in s proline biosynthesis. This enzyme is encoded by P5CS gene family. We cloned two homologous genes P5CS from sugarcane, (Accession Number : SoP5CS1 KF178299) and (Accession Number : SoP5CS2 KF178300), which encode 729 and 716 amino acid polypeptide . The between these genes was s identity two 74% based on nucleotide sequence . The s SoP5CS1 gene had 98% with (Accession identity SbP5CS1 Number : GQ377719.1) and had 99% SoP5CS2 identity with (Accession Number : EF113257.1). In this SaP5CS experiment, sugarcane were exposed to plantlets medium containing PEG 6000 (40%) for 12, 24, 48, and 72 hours. roline concentration P was measured after treatment genes were zed and expression analy by real time qPCR. The results showed that the proline concentration was increased 12 folds (9 8 umol g ) after . . -1 48-hours stress treatment. ighest expression of The h SoP5CS1 occured at 24-hours treatment with approximately 16 times from plant without PEG (control plant) and decreased gradually at 48 and 72 hours treatment. ighest expression of occured The h SoP5CS2 at 24-hours drought stress with approximately 3 6 folds . compared to control. In drought treatment, the expression level was higher than and has SoP5CS1 SoP5CS2 increased signi cantly at 12-hours treatment. t I is suggested that the gene contributes more SoP5CS1 signi cantly to the production of proline during drought stress than . , could potential SoP5CS2 SoP5CS1 Hence y be used as a marker to screen sugarcane variety for drought tolerance for the development of transgenic and plant tolerant to drought.