The auxin conjugate indole-3-acetyl-aspartate affects responses to cadmium and salt stress in Pisum sativum L.

详细信息    查看全文

• 作者：Maciej Ostrowski ; ^{maciejost@umk.pl" class="auth_mail" title="E-mail the corresponding author} ; Anna Ciarkowska ; Anna Jakubowska
• 关键词：ABA ; abscisic acid ; AEC ; 3-amine-9-ethylcarbazole ; APX ; ascorbate peroxidase ; CAT ; catalase ; DNP ; dinitrophenol ; FIN219 ; far-red insensitive 219 ; GH3 ; Gretchen Hagen 3 ; GPX ; guaiacol peroxidase ; IAA ; indole-3-acetic acid ; IAA-Asp ; indole-3-acetyl-aspartate ; ICA-Cys ; indole-3-carboxyl-cysteinate ; JA ; jasmonic acid ; JAR1 ; jasmonate resistance 1 ; PAGE ; polacrylamide gel electrophoresis ; PCD ; programmed cell death ; POX ; peroxidase ; ROS ; reactive oxygen species ; SA ; salicylic acid ; SA-Asp ; salicyloyl
• 刊名：Journal of Plant Physiology
• 出版年：2016
• 出版时间：1 February 2016
• 年：2016
• 卷：191
• 期：Complete
• 页码：63-72
• 全文大小：2430 K

文摘

The synthesis of IAA-amino acid conjugates is one of the crucial regulatory mechanisms for the control of auxin activity during physiological and pathophysiological responses. Indole-3-acetyl-aspartate (IAA-Asp) is a low molecular weight amide conjugate that predominates in pea (Pisum sativum L.) tissues. IAA-Asp acts as an intermediate during the auxin degradation pathway. However, some recent investigations suggest a direct signaling function of this conjugate in various processes. In this study, we examine the effect of 100 μM IAA-Asp alone and in combination with salt stress (160 mM NaCl) or heavy metal stress (250 μM CdCl₂) on H₂O₂ concentration, protein carbonylation as well as catalase and ascorbate (APX) and guaiacol peroxidase (GPX) activities in 7-day-old pea seedlings. As revealed by spectrophotometric analyses, IAA-Asp increased the carbonylated protein level and reduced the H₂O₂ concentration. Moreover, IAA-aspartate potentiated the effect of both Cd²⁺ ions and NaCl on the H₂O₂ level. The enzymatic activities (catalase and peroxidases) were examined using spectrophotometric and native-PAGE assays. IAA-Asp alone did not affect catalase activity, whereas the two peroxidases were regulated differently. IAA-Asp reduced the APX activity during 48 h cultivation. APX activity was potentiated by IAA-Asp + NaCl after 48 h. Guaiacol peroxidase activity was diminished by all tested compounds. Based on these results, we suggest that IAA-Asp can directly and specifically affect the pea responses to abiotic stress.