Alleviation of changes in protein metabolism in NaCl-stressed wheat seedlings by thiamine

NaCl-stress induced a pronounced suppression in growth of wheat seedlings. The most abundant amino acids (cysteine, arginine, methionine) constituting about 55 % of total free amino acid content in control wheat were reduced in 100 mM NaCl-treated plants. However, valine, isoleucine, aspartic acid a nd proline accumulated in response to NaCl stress and NaCl-treated wheat se edlings showed 1.6 fold increase in total free amino acids compared to the control. Addition of 2 muM thiamine alleviated the effects of NaCl on the a mino acid composition and the amount of total free amino acids decreased to that in the control. Content of 26 kDa protein increased in NaCl-treated p lants, stimulation was more pronounced in roots than in shoots. In contrast , the contents of 13 and 20 kDa proteins decreased. After addition of thiam ine, the 24 kDa protein, which disappeared with NaCl treatment, has been in itiated again. Moreover, thiamine treatment stimulated the accumulation of the 20 kDa protein.