Effects of NaCl on protein profiles of tetraploid and hexaploid wheat species and their diploid wild progenitors

Abstract

The soluble proteins extracted from the first leaf tissues of cultivated tetraploid (Triticum durum Desf., genome AB) and hexaploid (T. aestivum L., genome ABD) wheat species and their diploid wild progenitors [T. monococcum L. (A), Aegilops speltoides Tausch (B), and Aegilops tauschii Cosson (D)] exposed to 100 mmol/1 NaCl stress were separated by two-dimensional (2D) gel electrophoresis. There was no newly synthesized protein in the NaCl treatment compared to the control treatment in all species. However, protein profiles showed some differences among species. Most of these proteins had acidic character; their isoelectric point (pl = pH - acidity of proteins) ranged between 5.1-6.9 and low-mol weight (LMW) between 20.3-30.6 kDa. Salt stress caused some proteins to increase or decrease. In the same MW and pl, 11 LMW and 3 intermediate-mol weight (IMW, 34.8-35.4 kDa) proteins increased and/or decreased in amounts were common between at least two species. The remarkable changes in Ae. speltoides were detected as decreases or losses in protein profiles. As a result of salt stress, all the remarkable changes in T. durum were detected as the increases in proteins. However, some proteins increased in T. aestivum, T. monococcum and Ae. tauschii. It is suggested that an increase in the amount of the proteins may lead to an increase in the tolerance mechanisms towards NaCl salinity of wheat species which has A and/or genome(s).