Transcriptomic and physiological responses of rice to lanthanum stress
This study investigated the physiological and molecular responses of rice (Oryza sativa) to lanthanum (La) stress, with a focus on La uptake and translocation, detoxification, calcium-La interactions, and root stress responses. Physiological and elemental analyses showed that La predominantly accumulated in rice roots and affected the accumulation of several mineral nutrients. Exogenous calcium alleviated La-induced inhibition of root growth, although this effect was not associated with a clear competitive relationship between Ca and La uptake. Genetic analyses using OsNRAMP4 and OsPCS mutants were performed to evaluate their potential roles in La uptake and detoxification. In addition, root cell viability was examined under different La concentrations. To further characterize the molecular responses to La stress, Nipponbare rice seedlings were treated with 0 or 10 uM LaCl3 for 24 h, and root samples were collected for transcriptome sequencing with three biological replicates per treatment. Differential expression and functional enrichment analyses revealed responses associated with cell wall-related processes, redox regulation, phenylpropanoid biosynthesis, plant hormone signaling, MAPK signaling, and glutathione metabolism. These data provide a transcriptomic resource for understanding the molecular mechanisms underlying rice responses to lanthanum stress.