TaWRKY13-A Serves as a Mediator of Jasmonic Acid-Related Leaf Senescence by Modulating Jasmonic Acid Biosynthesis.

Leaf senescence is crucial for crop yield and quality. Transcriptional regulation is a key step for integrating various senescence-related signals into the nucleus. However, few regulators of senescence implicating transcriptional events have been functionally characterized in wheat. Based on our RNA-seq data, we identified a WRKY transcription factor, TaWRKY13-A, that predominately expresses at senescent stages. By using the virus-induced gene silencing (VIGS) method, we manifested impaired transcription of leading to a delayed leaf senescence phenotype in wheat. Moreover, the overexpression () of accelerated the onset of leaf senescence under both natural growth condition and darkness in and . Furthermore, by physiological and molecular investigations, we verified that TaWRKY13-A participates in the regulation of leaf senescence jasmonic acid (JA) pathway. The expression of JA biosynthetic genes, including , was altered in -overexpressing . We also demonstrated that TaWRKY13-A can interact with the promoter of and by using the electrophoretic mobility shift assay (EMSA) and luciferase reporter system. Consistently, we detected a higher JA level in -overexpressing lines than that in Col-0. Moreover, our data suggested that TaWRKY13-A is partially functional conserved with AtWRKY53 in age-dependent leaf senescence. Collectively, this study manifests TaWRKY13-A as a positive regulator of JA-related leaf senescence, which could be a new clue for molecular breeding in wheat.