A cellular view of drought adaptation in sugarcane: multi-omics integration reveals a quadruple module network linking water regulation, oxidative defense, cell wall remodeling, and cell cycle regulation

Saccharum spp., a globally important crop for sugar and bioenergy production, suffers substantial yield losses due to drought. Whole-plant studies are complicated by inherent tissue heterogeneity and organ-level interactions. To dissect this complexity, we established a homogeneous suspension cell line from the drought-tolerant cultivar ‘Roc22’. A gradient of polyethylene glycol 6000 (PEG-6000)-induced drought stress (0%, 5%, 10%, 20%) was applied, enabling integrated cytological, physiological, and transcriptomic analysis. Cytological analysis revealed a concentration-dependent decline in cell viability under drought stress, with survival rates dropping to 45.5% after 8 h of 20% PEG treatment. Cells exhibited browning, shrinkage, and ultrastructural damage (affecting the plasma membrane, mitochondria, and nucleus), with severe stress triggering programmed cell death (PCD). Physiological analysis showed that malondialdehyde (MDA) content peaked under 10% PEG treatment (17.16 μmol g −1 FW, representing a 68.55% increase over the control), soluble sugar content accumulated progressively with stress intensity (increasing by 45.64% at 20% PEG), while soluble protein content decreased significantly (a reduction of 82.9% at 20% PEG). Antioxidant enzyme activities responded differentially. Transcriptome profiling identified 9,923 differentially expressed genes (DEGs). Protein-protein interaction (PPI) network analysis pinpointed 21 core candidates, including aquaporins ( e.g. , TIP3-1 , NIP1-1 ), cell wall modifiers ( e.g., XTH23 , CESA1 ), peroxidases ( e.g. , PER25 ), and antioxidant enzymes ( e.g. , APX1 , which was strikingly up-regulated 6.22-fold).This study provides a systematic dissection of th e multi-dimensional drought response network in sugarcane at the cellular level, integrating water regulation, oxidative defense, cell wall remodeling, and cell cycleregulation. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) validation of nine candidate genes confirmed the reliability of the transcriptomic data. Our findings offer deep mechanistic insights and establish a novel “cell model + multi-omics” paradigm for crop stress biology research.