Increased accumulation of pathogenesis-related proteins in response of lupine roots to various abiotic stresses

The accumulation of specific stress proteins is a common response of plants to various environmental stresses. It was previously described that lead stimulated the accumulation of 16 kDa polypeptides, which were identified as a member of PR-10 pathogenesis related proteins [J. Plant Physiol. 154 (1999) 703]. Here we have shown that other stress factors, which inhibited root growth of Lupinus luteus L., such as cadmium, zinc, copper, osmotic and salt stress also induced the accumulation of 16 kDa polypeptides. Enhanced level of the 16 kDa polypeptides was also found in roots exposed to salicylic acid, hydrogen peroxide and ethylene, substances considered as transducters of the stress signal in plants. SDS-PAGE analysis followed by Western blotting confirmed that these polypeptides are immunologically related to PR-10 proteins. These data provide evidences that plant defense might involve the same proteins in response to various stressors. Moreover, the results indicate that signalling substances like salicylic acid, hydrogen peroxide and ethylene are per se capable to induce the synthesis of these proteins as well. (C) 2004 Elsevier B.V. All rights reserved.