From symbiosis to synthesis: Advances in the biosynthesis and regulation of active ingredients in Gastrodia elata

Gastrodia elata Blume (Tianma) is a fully mycoheterotrophic orchid and an important traditional Chinese medicine. Its principal phenolic glycosides, gastrodin and parishins, show neuroprotective, anti-inflammatory and antioxidant activities. The plant depends on Mycena spp. for seed germination and Armillaria spp. for vegetative growth, and this obligate symbiosis has shaped genome evolution, carbon acquisition and specialized metabolism. Here, we synthesize multi-omics and biochemical evidence for endogenous active-ingredient biosynthesis in G. elata . We delineate shikimate-derived aromatic precursor supply, the candidate phenylpropanoid and β -oxidative route to gastrodin, provisional parishin assembly, and the type III polyketide synthase branch associated with flavonoid diversification. We also assess fungal, hormonal and transcriptional signals that may coordinate metabolite accumulation with development and symbiosis. By distinguishing biochemically supported steps from omics-supported inferences, this review defines priorities for enzyme validation, flux analysis, cultivation and quality-oriented breeding.