Abstract
Excess salt is harmful for plants. However, halophytes have developed the mechanism of salt tolerance to adapt themselves to high salinity. Sheep grass belongs to Poaceae and it can grow under 500 mM NaCl, although the remarkable structural feature, such as salt grands or bladders, was not observed. Previously, we cloned the salt-inducible plasma membrane protein 3 genes (AcPMP3) from sheep grass. Expression of AcPMP3 was up-regulated under salt, drought, cold, ABA and H2O2 treatments. To investigate the function of AcPMP3 under salt stress, salt sensitive yeast (YR93-31; Δpmp3, Δnha1, Δpmr2) was transformed with AcPMP3. Consequently, overexpression of AcPMP3 could recover salt tolerance in YR93-31 under high NaCl and KCl conditions, and decrease cellular Na+ and K+ accumulation. AcPMP3 mRNA was abundant in mesophyll and root epidermis cells, and it might regulate Na+ and K+ accumulation in their cells under salt stress.
