Seed Proteome Analysis of Tall Wheatgrass under Drought and Low Temperature Conditions

Tall wheatgrass (Agropyronelongatum) is native to Iran and is used in a wide area of rangelands and also used in drylandseeding program. This plant produces green and dry fodder and has a great importance in protecting drylands from water and wind erosion.Seed proteome analysis was conducted under three conditions, namley, optimum (20 °C and zero water potential), drought conditions (20 °C and – 6 bar), and low temperature (6 °C and zero water potential). Seed sampling was conducted after 14, 36 and 96 hours of imbibition and before radicle protrusion. Comparing all the treatments, proteome analysis showed that 114 spot exhibited either up or down regulation. The highest variation of spots (78 spots) was detected by comparing germinated seeds under low and drought conditions, of which, 65 spots were up-regulated and 13 spots were down-regulated. The lowest spot variation was detected by comparing germinated seeds under optimum and drought conditions. 35 spots involved in storage proteins (glutenin, globulin and Avenin), 34 spots in starch (β-amylase and starch synthase) and sucrose (sucrose synthase) metabolism.Most of the down-regulated proteins were chaperonins (heat shock proteins) and antioxidant (peroxiredoxin); some of them had a dual role (like serpin and α-amlase inhibitor).