Identification and functional analysis of the remorin gene TaREM4.3-A from wheat (Triticum aestivum L.)

Remorin (REM) proteins play a pivotal role in plant growth and development. However, their functional characterization remains relatively limited in wheat. In this study, we identified the TaREM4.3-A gene, which belongs to group IV of the remorin family. The transcriptional levels of TaREM4.3-A were significantly upregulated by abscisic acid (ABA), polyethylene glycol (PEG), and NaCl treatments, whereas it showed no response to exogenous brassinosteroid (BR) or cold treatment. Yeast one-hybrid and dual-luciferase reporter assays demonstrated that the Triticum aestivum basic leucine zipper 60 (TabZIP60) transcription factor (TF) positively regulates TaREM4.3-A expression by binding to its promoter region. Consistently, the expression level of TaREM4.3-A was notably enhanced in TabZIP60-overexpressing transgenic wheat lines. Overexpression of TaREM4.3-A in Arabidopsis resulted in reduced plant height and root growth rate, as well as inhibited BR biosynthesis and signaling pathways. Additionally, TaREM4.3-A overexpression delayed seed germination by modulating ABA and gibberellic acid (GA3) contents, as well as the expression levels of ABA/GA metabolism-related genes (AtCYP707A2, AtGA3ox1, and AtGA3ox2). Collectively, our findings indicate that TaREM4.3-A regulates seed germination, plant growth and development through the GA, ABA, and BR signaling pathways.