The transcription factor ANAC053 confers aluminum tolerance via regulation of a cell wall modifying gene

Cell wall modification alters plant resistance to aluminum (Al), although the mechanisms remain unclear. In this study, we identified the No Apical Meristem (NAM), Arabidopsis Transcription Factor 1/2 (ATAF1/2) and Cup-shaped Cotyledon 2 (CUC2) (NAC) transcription factor (TF) ANAC053 as crucial for Al resistance in Arabidopsis. (Arabidopsis thaliana) Al caused a concurrent increase in ANAC053 transcript and protein accumulation, and anac053 mutants were sensitive to Al, whereas transgenic lines overexpressing ANAC053 exhibited reduced Al sensitivity. Additionally, the anac053 mutants possessed elevated xyloglucan levels, causing higher cell wall Al fixation capacity and indicating that ANAC053 affects Al accumulation in the roots. We revealed that ANAC053 directly regulates the expression of XYLOGLUCAN ENDOTRANSGLUCOSYLASE HYDROLASE 15 (XTH15), which is primarily responsible for xyloglucan remodeling. In conclusion, our findings show that ANAC053 directly regulates cell wall modification-associated genes that are necessary for root growth under Al stress and that plant Al tolerance is dictated by the capacity of ANAC053 to sequester Al within the root cell wall.