New Insights into the Biosynthetic Mechanism Differences in the Health and Nutritional Functions of Different Fruiting Body Parts of Helvella leucopus

Helvella leucopus, as a precious and endangered wild edible fungus with high nutritional and health value, has its cap and stipe each exhibiting unique advantages in nutritional and health functions. To elucidate the biological basis underlying the functional differences in different parts of the fruiting body, this study employed integrated transcriptomics and metabolomics approaches to investigate the gene expression and metabolic differences between the cap and stipe of H. leucopus. Metabolomic analysis revealed that the cap is rich in health-active components such as sterols and alkaloids, whereas the stipe contains abundant nutritional components such as glycerophospholipids and amino acids. Transcriptomic results indicated that genes related to sterol synthesis (e.g., ERG1, ERG3, ERG6) and energy metabolism (e.g., PGK1, ENO1, PYK1) are highly expressed in the cap, suggesting more active metabolic processes. Integrated omics analysis identified significant enrichment in riboflavin metabolism, pantothenate and CoA biosynthesis, and terpenoid backbone biosynthesis, which are associated with the functional differences between the cap and stipe. The constructed biological pathway network diagram elucidated the differential biosynthetic mechanisms of key health and nutritional components, including sterols, alkaloids, linoleic acid derivatives, glycerophospholipids, and amino acids, between the cap and stipe. These findings not only reveal the biological basis for the higher health value of the cap and the higher nutritional value of the stipe in H. leucopus but also provide a theoretical foundation for its food development and the study of functional differences in nutritional components between different parts of the fruiting body.