Translational regulation of ion transporters modules mineral homestasis in tea roots under phosphate aluminum interaction

• DEGs analysis revealed mineral uptake regulators under varying P and Al conditions in tea roots. • Al suppressed CsPHTs expression to limit cellular P uptake. • P enhanced Al concentration via transcriptional induction of CsMATE transporters. • Coordinated transcriptional regulation of Ca and K transporters maintained P-Ca-K homeostasis in tea roots. • Al-Mg interaction exhibited P-dependent antagonism in tea roots. The tea plant ( Camellia sinensis ) is predominantly cultivated in acidic soils, and demonstrates significant accumulation of Al in its root and leaf tissues. P is a key macronutrient required for the growth of tea plants. However, the mechanistic basis underlying Al’s influence on the mineral nutrition homeostasis under varying P concentrations remains unclear. Here, to mitigate ionic interactions in solution, we adopted alternating treatment of P and Al to investigate the combined effects on mineral element uptake and transcriptional profiles of tea plants. A total of 3522 annotated differentially expressed genes (DEGs) were obtained by transcriptome sequencing, with a large number of DEGs associated with mineral transport mechanisms, including transmembrane transporters and channel regulators. Notably, P significantly upregulated CsMATE genes expression, key mediators of Al transport, thereby enhancing the accumulation of Al in tea roots. Concurrently, Al exposure induced the transcriptional activation of P transport systems, specifically the CsPHT and CsPHO1 gene families. Intriguingly, while Ca and K exhibited synergistic regulation of P-Ca-K homeostasis, Al-Mg interaction displayed P-dependent antagonism within the roots. Four key transporters, CsPHT1–9, CsPHO1, CsPHO1; H1–1, and CsPHO1; H1–2, were functionally characterized through yeast heterologous expression, confirming their roles in P transport. Our research indicated that Al exposure in high-P conditions coordinated dual regulatory mechanisms, both direct transcriptional control via CsPHT1/PHO1 transporters and indirect modulation through ionic balance, collectively maintaining elemental homeostasis in tea plants. This study provides new insights and genetic resources for plant nutrient regulation in acidic soils and for Al-tolerant crop breeding.