DIA (Data Independent Acquisition) proteomic based study on maize filling-kernel stage drought stress-responsive proteins and metabolic pathways

Drought is one of the most severe environmental stressors hampering maize (Zea mays L.) production worldwide. Therefore, revealing the molecular mechanisms underpinning maize drought tolerance is critical for guiding drought resistance breeding and ensuring global food security. Herein, we performed a data-independent acquisition (DIA) proteomics-based comparative analysis of the proteome responses of two contrasting maize hybrids (drought-tolerant NongDan 476 and drought-sensitive ZhongXin 978) exposed to 12 days of water-deficit (drought) treatment at the kernel filling stage. Resultantly, our DIA-based analysis approach identified a total of 826 differentially abundant proteins (DAPs), among which 7 DAPs were specifically accumulated in tolerant genotype ND 476 under drought treatment conditions. Moreover, our results showed that there were significant differences in drought stress responses between the two hybrids at the proteomic level. Predominantly, our analysis revealed that maize drought tolerance is attributed to some key proteins such as chaperones, DNA replication related enzymes, vicilin and ABA-responsive RAB17 protein, participating in several metabolic networks including starch and sucrose metabolism, terpenoid backbone biosynthesis, cyanoamino acid metabolism and carbon metabolism pathways. Our findings provide further insights into the drought stress tolerance mechanisms in maize at the grain filling period, in addition to useful reference data for maize drought resistance breeding.