Integrated transcriptomic and metabolomic analysis the variation of rice cultivars response to arsenite stress

Arsenic (As) is considered to be a carcinogen that tends to be accumulated in rice. However, the molecular mechanism of crop response to As is not sufficiently understood. In the study, M2 and L5 were screened out from 16 experimental cultivars as sensitive and tolerant ones based on the phenotypic changes between As(III) treated and control group, respectively. A total of 11052 significant differential expression genes (DEGs) and 918 significantly differentially accumulated metabolites (DAMs) were identified by using the comparative transcriptomic and metabolomic analysis. The KEGG pathway analysis suggesting that As(III) stress could effectively induce the production of DEGs related to rice defense function to improve plant tolerance responses to As(III) toxicity. The variation of DEGs metabolic pathways between two comparison groups was mainly concerning plant growth. The metabolomic analysis demonstrated that DAMs detected in M2 and L5 were principally enriched in the pathway related to plant growth, development and stress tolerance. The dermatan L-iduronate was the largest contributors of the two pairwise groups to separating metabolites in As(III) treated to control group. The combined transcriptome and metabolome analysis revealed that changes of the DAMs in M2 and L5 comparison groups regulated by DEGs resulted in variation in phenotype and arsenic accumulation between the two cultivars. This study provides insight into the molecular mechanisms related to the response and processes involved in toxic effects and adaptive strategies to As(III) stress.