Fig. 6

Integrated correlation analysis of the transcriptome and metabolome. (A) Pearson correlation analysis identifies significant associations between 58 differentially abundant metabolites (DAMs) and 778 differentially expressed genes (DEGs). The correlation matrix highlights positive and negative correlations, with the strength of associations represented by color gradients. (B) Bubble plot displays the results of integrated pathway enrichment analysis combining transcriptomic and metabolomic data. Pathways with significant enrichment are shown, with bubble size representing the impact value and color intensity reflecting statistical significance (P-value). (C) Adenine metabolism pathway expression profiles. The expression levels of key metabolites and genes involved in the adenine metabolism pathway are shown for the CON and HU groups. Expression patterns highlight changes induced by microgravity. Xdh (xanthine dehydrogenase) expression is positively correlated with hypoxanthine levels (R = 0.9972, P < 0.0001) and xanthine levels (R = 0.9957, P < 0.0001). (D) Pathway-specific correlation analysis. Correlation analysis across eight signaling pathways identifies associations between differential genes and metabolites. Results are visualized through heatmaps, with key pathways such as purine metabolism and MAPK signaling prominently displayed. Strong correlations (P < 0.05 and|Rho| > 0.85) are highlighted with colors: red indicates positive correlations, and green indicates negative correlations